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Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Names On Vietnam War Memorial Wall To Fly In Space Привет всем! Вот, свалилось из Internet... MEDIA RELATIONS OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011 http://www.jpl.nasa.gov Contact: Mary Beth Murrill FOR IMMEDIATE RELEASE July 1, 1998 NAMES ON VIETNAM WAR MEMORIAL WALL TO FLY IN SPACE Names inscribed on the Vietnam Veterans Memorial in Washington, D.C. will be engraved on a microchip that will fly in space on NASA's Stardust mission to a comet, project officials have announced. The names will join those of more than 400,000 people who have already submitted their names to fly, free-of-charge, on the Stardust spacecraft, which is scheduled for launch next February on a round-trip to a comet. "This almost will be like sending a miniature version of the Vietnam Memorial into space as an eternal tribute to those who fell in America's longest war," said Jan Scruggs, founder and president of the Vietnam Veterans Memorial Fund. There are 58,214 names inscribed on the memorial, Scruggs said. Approximately 2,500,000 people visit "The Wall" each year, making the Vietnam Veterans Memorial the most visited in Washington, D.C. Stardust's prime mission is to return a sample of comet dust to Earth in 2006. The "Send Your Name to a Comet" effort has drawn attention from around the world as people submit their names via the Internet to the Stardust Project at NASA's Jet Propulsion Laboratory in Pasadena, CA. "We wanted to honor the memory of those who fell in the war," said Project Manager Dr. Kenneth Atkins, himself a Vietnam- era Air Force pilot with the Strategic Air Command from 1959 to 1968. "This is also an opportunity for veterans, their families and loved ones to create a special remembrance by having their names united on this peaceful exploration of space," he added. Included is the name of Air Force pilot Michael J. Blassie, whose remains were this week identified and disinterred from the Tomb of the Unknowns at Arlington National Cemetery. Atkins of JPL and Scruggs of the Vietnam Memorial both hope to link their education efforts to broaden the audiences of their respective organizations. The Stardust project hopes to exhibit all the collected names in a museum after the comet sample has returned to Earth, Atkins said. The names are electronically etched onto a fingernail-size silicon chip at JPL's Microdevices Lab. Writing on the microchip is so small that about 80 letters would equal the width of a human hair. Once inscribed, the names can be read only with the aid of an electron microscope. The web page and a project-sponsored network of educators across the country are two of the main efforts Stardust is using to bring information about the mission, its science plans and eventual discoveries to as broad an audience as possible. Scientists have long sought a direct sample of a comet particle because these icy bodies are thought to be nearly pristine examples of the original material from which the Sun and planets were born 4.6 billion years ago. Stardust's mission is to travel to within 150 kilometers (100 miles) of the nucleus of Comet Wild-2 (pronounced "Vilt-2"), gather comet dust particles and deliver them back to Earth. En route to the comet, Stardust will attempt to capture interstellar particles that are believed to be blowing through the solar system. In January 2006, mission plans call for the Stardust sample return capsule to parachute to a designated landing spot in the Utah desert . Names may only be submitted electronically and may be sent to the Stardust web page at http://stardust.jpl.nasa.gov . Those submitting their names are granting permission for the Stardust project and its partners to use the names submitted in possible future exhibits and/or publications. More information about the Vietnam Veterans Memorial Fund is at http://www.vvmf.org . Stardust, managed for NASA's Space Science Division and is a collaborative partnership between the University of Washington, Lockheed Martin Astronautics, and JPL/Caltech. Stardust is the fourth mission to be chosen under NASA's Discovery Program of low-cost solar system projects, and follows the Mars Pathfinder, Near Earth Asteroid Rendezvous (NEAR) and Lunar Prospector missions. The goal of the Discovery Program is to launch many small missions that perform focused science with fast turn-around times, cost less than $150 million (in fiscal year 1992 dollars) to build, and are joint efforts with industry, small business and universities. JPL is a division of the California Institute of Technology. ##### Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Astronaut Andy Thomas To Discuss Mir Mission Привет всем! Вот, свалилось из Internet... Jennifer McCarter Headquarters, Washington, DC July 2, 1998 (Phone: 202/358-1639) Eileen M. Hawley Johnson Space Center, Houston, TX (Phone: 281/483-5111) NOTE TO EDITORS: N98-44 ASTRONAUT ANDY THOMAS TO DISCUSS MIR MISSION Astronaut Andy Thomas, the final American to live on board the Russian Mir space station, will discuss his journey during a news conference Wednesday, July 8, beginning at 9 a.m. EDT. Frank Culbertson, manager of the Phase 1 Shuttle/Mir program, also will participate in the briefing to discuss Thomas' tenure on Mir and review the program, which saw seven Americans live and work on board the Russian space station. The press conference will originate from NASA's Johnson Space Center, Houston, TX, and will be broadcast on NASA Television, providing multi-center question and answer capability for reporters at participating NASA centers. During his 130 days on board Mir, Thomas traveled more than 56 million miles. He launched as a member of the STS-89 crew on Jan. 22, 1998, becoming a Mir crew member on Jan. 24. He returned on board Discovery as a member of the STS-91 crew on June 12. When Thomas returned to Earth, he concluded 802 consecutive days of an American presence on board Mir, beginning with astronaut Shannon Lucid's arrival March 24, 1996. The press conference can be seen on NASA Television, which is carried on GE-2, Transponder 9C, at 85 degrees West longitude, vertical polarization, frequency 3880 Mhz, audio 6.8 Mhz. Media planning to attend the briefing at the Johnson Space Center should contact that newsroom by 5 p.m. EDT on July 6 for accreditation. -end- Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Mars Surveyor 98 Update - July 3, 1998 Привет всем! Вот, свалилось из Internet... 1998 MARS SURVEYOR PROJECT STATUS REPORT July 3, 1998 John McNamee Mars Surveyor 98 Project Manager Orbiter integration and test activities are proceeding on schedule. Troubleshooting of the Pressure Modulator InfraRed Radiometer (PMIRR) instrument optical chopper assembly at Honeywell has uncovered a faulty bearing in the chopper. This bearing is the suspected cause of the chopper anomalies which surfaced during system testing. The Thermal and Evolved Gas Analyzer (TEGA) flight instrument and the repaired flight meteorology mast were delivered to Lockheed Martin on July 2 for installation on the lander on July 6. This completes the lander flight science payload delivery and the full flight payload will be installed on the lander for the landed thermal balance test scheduled to begin on July 18. The medium gain antenna (MGA) on the lander was damaged during a mission profile test on June 30 due to an incorrect physical configuration of the vehicle. The MGA was moving in a normal fashion during the test when it contacted one of the lander outboard solar panels. The incorrect physical configuration involved the conduct of the test with the outboard arrays tucked up in a stowed configuration against the inboard panel rather than in the deployed configuration (which would be the normal flight configuration during any MGA motion). The inboard arrays contain notches to accommodate the full design range of MGA motion while the outboard arrays contain no notches. The technicians in the test facility noticed the problem as it was occurring but were unable to stop the MGA motion due to two other contributing factors to the incident: 1) The lander was operating on battery power which rendered the kill switch inoperative, and 2) The mission sequence was at a point of transition from X-band to UHF transmission capability which made it impossible to command the vehicle at a time when MGA motion was occurring. The damage appears to be limited to the MGA with no visible damage evident on the solar array. The MGA was shipped to Boeing on July 1 for assessment and repair. Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Hubble Simulcast Links Outer Space To Cyberspace Привет всем! Вот, свалилось из Internet... FOR RELEASE WEDNESDAY JULY 1, 1998 Contact: Ray Villard Space Telescope Science Institute, Baltimore, MD 410-338-4514 PRESS RELEASE: STScI-PR98-24 HUBBLE SIMULCAST LINKS OUTER SPACE TO CYBERSPACE Expanding its broadcast universe far beyond the Baltimore area and into cyberspace, the popular WJHU radio program "The Marc Steiner Show" (WJHU, FM 88.1), has teamed up with NASA's Space Telescope Science Institute (STScI) to take listeners on a Hubble Space Telescope tour of the cosmos via the Internet. For the show's first time, host Marc Steiner's discussion and interview with his guests will be available on the World Wide Web, courtesy of STScI's Office of Public Outreach. Even if people miss the July 7 live broadcast, STScI will make the recorded program, with dazzling Hubble Telescope images added, available on the Internet for space enthusiasts to listen to in their leisure time. The hour-long program's guests are Dr. Carol Christian and Dr. Mario Livio from STScI, and IMAX/Planetarium director Jim O'Leary from the Maryland Science Center, a popular Baltimore Inner Harbor attraction. The experts will describe the latest Hubble discoveries, notably, recent observations of the spectacular and colorful deaths of stars like our sun. The guests will also answer listeners' questions over a broad range of astronomical topics, and tell the story behind the headlines of some of Hubble's most dramatic findings. "My talk show tackles all sorts of intriguing topics, but bringing Hubble results and even pictures to a worldwide audience with commentary by leading Hubble astronomers is an especially exciting opportunity," says radio host Marc Steiner. "This is groundbreaking work for public radio, bringing you a live broadcast with pictures and text during our conversation. We are marrying the forms of media." "The astronomers at STScI are enthusiastic about sharing the dramatic imagery and latest science results from NASA's Hubble Space Telescope through innovative ways on the Internet," says Carol Christian, head of the Institute's Office of Public Outreach. "A simulcast with the Marc Steiner's program is a great merging of broadcast radio with the Web." For listeners to "tune in" via the Internet, they need a free software package "plug in" called Real Audio. This software can be downloaded into a home computer from the following URL: http://www.real.com/products/player/index.html. Before the show, listeners need to use their computers and Internet access to reach the site, and follow the directions for downloading and installing the software. The program, which will be broadcast at 12 noon on Tuesday July 7, can be accessed on the internet at the following URL: http://hubble.stsci.edu/steiner/ "After the show listeners will still be able to access the site and log into any part of the discussion they want, hearing that portion of the conversation, seeing the videos and photo's and accessing documents," says Steiner. "Also we want to hear their comments and critiques, and so listeners are welcomed to e-mail us." "The Marc Steiner Show" airs weekdays from noon to 2 p.m. on WJHU, Baltimore's National Public Radio member station and a radio service of The Johns Hopkins University. The Space Telescope Science Institute is the research center for conducting Hubble Telescope observations, and will also operate the successor to Hubble, called the Next Generation Space Telescope, to be launched in the year 2007. END Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [1/6] Привет всем! Вот, свалилось из Internet... International Meteor Organization 1999 Meteor Shower Calendar (Net-Version) ========================================= compiled by Alastair McBeath based on data in IMO Monograph No.2: Handbook for Visual Meteor Observers, edited by Juergen Rendtel, Rainer Arlt and Alastair McBeath, IMO, 1995; with additional contributions from Rainer Arlt and Marc de Lignie. Layout by Andre Knoefel. Introduction Welcome to the 1999 International Meteor Organization (IMO) Meteor Shower Calendar. The year promises to be another interesting one, with many major showers free from moonlight interference (except the Quadrantids, eta- Aquarids, Southern delta-Aquarids and Orionids). The Leonids may possibly produce high to very high activity in November, while in August, the millennium's last total solar eclipse ensures perfect conditions for the Perseids. Do not forget that monitoring of meteor activity should ideally be carried on throughout the rest of the year too, however! We appreciate that this is not practical for many observers, and this Calendar was devised as a means of helping observers deal with reality by highlighting times when a particular effort may most usefully be employed. Although we include to-the- hour predictions for all the more active night-time and daytime shower maxima, based on the best available data, please note that in many cases, such maxima are not known more precisely than to the nearest 1deg of solar longitude (even less accurately for the daytime radio showers, which have received little attention in recent years). In addition, variations in individual showers from year to year mean past returns are at best only a guide as to when even major shower peaks can be expected, plus as some showers are known to show particle mass-sorting within their meteoroid streams, the radio, telescopic, visual and photographic meteor maxima may occur at different times from one another, and not necessarily just in these showers. The majority of data available are for visual shower maxima, so this must be borne in mind when employing other observing techniques. The heart of the Calendar is the Working List of Visual Meteor Showers, thanks to regular updating from analyses using the IMO's Visual Meteor Database, the single most accurate listing available anywhere today for naked-eye meteor observing. Even this can never be a complete list of all meteor showers, since there are many showers which cannot be properly detected visually, and some which only photographic, radar, telescopic, or video observations can separate from the background sporadic meteors, present throughout the year. The IMO's aims are to encourage, collect, analyze, and publish combined meteor data obtained from sites all over the globe in order to further our understanding of the meteor activity detectable from the Earth's surface. Results from only a few localized places can never provide such total comprehension, and it is thanks to the efforts of the many IMO observers worldwide since 1988 that we have been able to achieve as much as we have to date. This is not a matter for complacency, however, since it is solely by the continued support of many people across the whole world that our steps towards constructing a better and more complete picture of the near-Earth meteoroid flux can proceed. This means that all meteor workers, wherever they are and whatever methods they use to record meteors, should follow the standard IMO observing guidelines when compiling their information, and submit their data promptly to the appropriate Commission for analysis. Visual and photographic techniques remain popular for nightly meteor coverage (weather permitting), although both suffer considerably from the presence of moonlight. Telescopic observations are less popular, but they allow the fine detail of shower radiant structures to be derived, and they permit very low activity showers to be accurately detected. Video methods have been dynamically applied in the last few years, and are starting to bear considerable fruit. These have the advantages, and disadvantages, of both photographic and telescopic observing, but are already increasing in importance. Radio receivers can be utilized at all times, regardless of clouds, moonlight, or daylight, and provide the only way in which 24-hour meteor observing can be accomplished for most latitudes. Together, these methods cover virtually the entire range of meteoroid sizes, from the very largest fireball-producing events (using all-sky photographic patrols or visual observations) through to tiny dust grains producing extremely faint telescopic or radio meteors. However and whenever you are able to observe, we wish you all a most successful year's work and very much look forward to receiving your data. Clear skies! January to March The year's first quarter brings several low activity showers, including the diffuse ecliptical stream complex, the Virginids, active from late January to mid-April. Of the two major showers, the northern-hemisphere Quadrantids (visual peak around January 3, 23h UT) are lost to bright moonlight. The southern-hemisphere alpha-Centaurids (maximum expected circa February 8, 10h UT) are somewhat better-placed, but the last quarter Moon rises around local midnight on February 8, a nuisance as the shower is most observable only after late evening. However, the minor delta-Cancrids benefit from new Moon in January, as do the gamma-Normids in March. Daylight radio peaks are due from the Capricornids/Sagittarids around 20h UT on February 1, and the chi- Capricornids on February 13, probably around 21h UT. Neither radio shower has been well-observed in recent times, and as both have radiants under 10deg-15deg west of the Sun at maximum, they cannot be regarded as visual targets even from the southern hemisphere. delta-Cancrids Active: January 1 - 24; Maximum: January 17 (lambda = 297deg); ZHR = 4; Radiant: alpha = 130deg, delta = +20deg, Radiant drift: see Table 3; size: alpha = 20deg x delta = 10deg; V = 28 km/s; r = 3.0; TFC: alpha = 115deg, delta = +24deg and alpha = 140deg, delta = +35deg (beta > 40deg N); alpha = 120deg, delta = -03deg and alpha = 140deg, delta = -03deg (beta < 40deg N). This minor stream is well-suited to telescopic observations, with its large, complex radiant area, that probably consists of several sub-centers. Many of its meteors are faint. It is probably an early part of the Virginid activity. Recent observations show the delta-Cancrid ZHR is unlikely to rise much above 3-4, and the visual maximum may fall around lambda = 291deg (1999 January 11). January's new Moon on January 17 provides an excellent opportunity for checking what happens this year. The long winter nights in the northern hemisphere provide a further incentive, though the radiant is above the horizon almost all night, whether your site is north or south of the equator. Even on January 11, the first half of the night is Moon-free for all observers. gamma-Normids Active: February 25 - March 22; Maximum: March 14 (lambda = 353deg); ZHR = 8; Radiant: alpha = 249deg, delta = -51deg, Radiant drift: see Table 3; Radius: 5deg; V = 56 km/s; r = 2.4; TFC: alpha = 225deg, delta = -26deg and alpha = 215deg, delta = -45deg (beta < 15deg S). gamma-Normid meteors are similar to the sporadics in appearance, and for most of their activity period, their ZHR is virtually undetectable above this background rate. The peak itself is normally quite sharp, with ZHRs of 3+ noted for only a day or two to either side of the maximum. Activity may vary somewhat at times, with occasional broader, or less obvious, maxima having been reported in the past. Post-midnight watching yields best results, when the radiant is rising to a reasonable elevation from southern hemisphere sites. The waning crescent Moon on March 14 rises around or after 02h local time south of the equator, and should cause only minor problems. All forms of observation can be carried out for the shower, although most northern observers will see nothing from it. Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [2/6] Привет всем! Вот, свалилось из Internet... April to June Meteor activity picks up towards the April-May boundary, with showers like the Lyrids, pi-Puppids (maximum due around April 24, 02h UT) and eta-Aquarids (peak between May 5, 10h UT to May 6, 11h UT), with both these latter sources suffering from moonlight this year. During May and June, most of the activity is in the daytime sky, with six shower peaks expected during this time. Although a few meteors from the o-Cetids and Arietids have been reported from tropical and southern hemisphere sites visually in previous years, sensible activity calculations cannot be carried out from such observations. For radio observers, the expected UT maxima for these showers are as follows: April Piscids -- April 20, 19h UT; delta-Piscids -- April 24, 19h UT; epsilon-Arietids -- May 9, 18h UT; May Arietids -- May 16, 19h UT; o-Cetids -- May 20, 17h UT; Arietids -- June 7, 21h UT; zeta-Perseids -- June 9, 20h UT; beta-Taurids -- June 28, 20h UT. The ecliptical complexes continue with some late Virginids and the best from the minor Sagittarids in May-June. Visual observers should also be alert for any possible June Lyrids this year. Lyrids Active: April 16 - 25; Maximum: April 22, 16h UT (lambda = 32.1deg); ZHR = 15 (can be variable, up to 90); Radiant: alpha = 271deg, delta = +34deg, Radiant drift: see Table 3; Radius: 5deg; V = 49 km/s; r = 2.9; TFC: alpha = 262deg, delta = +16deg and alpha = 282deg, delta = +19deg (beta > 10deg S). The Lyrids are best viewed from the northern hemisphere, but they are observable from many sites north and south of the equator, and are suitable for all forms of observation. Maximum rates are generally attained for only an hour or two at best, although in 1996, mean peak ZHRs of 15-20 persisted for around 8-12 hours. The ZHR can be rather erratic at times, a variability also seen in 1996, when rates ranged between 10-30 from hour to hour during the peak. The last high maximum occurred in 1982 over the USA, when a very short-lived ZHR of 90 was recorded. This unpredictability always makes the Lyrids a shower to watch, since we cannot say when the next unusual return may occur. As the shower's radiant rises during the night, watches can be usefully carried out from about 22:30 local time onwards. This year, the first quarter Moon sets around 01h-02h local time north of the equator, so will cause only slight problems in the early post-midnight period. The predicted maximum should favour sites in Eastern Russia and Asia if correct, but variations in the stream could mean this is not the case in actuality. June Lyrids Active: June 11 - 21; Maximum: June 16 (lambda = 85deg); ZHR = variable, 0 - 5; Radiant: alpha = 278deg, delta = +35deg, Radiant drift: June 10 alpha = 273deg, delta = +35deg, June 15 alpha = 277deg, delta = +35deg, June 20 alpha = 281deg, delta = +35deg; Radius: 5deg; V = 31 km/s; r = 3.0. This shower does not feature in the current IMO Working List of Visual Meteor Showers, as apart from some activity seen from northern hemisphere sites in a few years during the 1960s (first seen 1966) and 1970s, evidence for its existence has been virtually zero since. In 1996, several observers independently reported some June Lyrids, however, and because the shower's probable maximum benefits from a waxing crescent Moon this year, we urge all observers who can to cover this possible stream. The radiant is a few degrees south of the bright star Vega (alpha Lyrae), so will be well on-view throughout the short northern summer nights, but there are discrepancies in its position in the literature. All potential June Lyrids should be carefully plotted, paying especial attention to the meteors' apparent velocity. Confirmation or denial of activity from this source in 1999 would be very useful. July to September Minor shower activity continues apace from near-ecliptic sources throughout this quarter, first from the Sagittarids, then the Aquarid and Capricornid showers, and finally the Piscids into September. The two strongest sources, the Southern delta-Aquarids (peak on July 28, 12h UT) and the alpha- Capricornids (maximum July 30), are lost to July's full Moon, along with the less-active Piscis Austrinids and the Southern iota-Aquarids. However, the Pegasids and Phoenicids in July, the Perseids in August and the delta- Aurigids in September do much better. The Northern delta-Aquarid (around August 9) and kappa-Cygnid (August 18) maxima should be good too, but the alpha-Aurigids (peak due around September 1, 12h UT) are another lunar casualty, together with the most likely Piscid peak, on September 20. For daylight radio observations, the interest of May-June has waned, but there remain the visually-inaccessible gamma-Leonids (peak circa August 25, 21h UT), and a tricky visual shower, the Sextantids (maximum expected September 27, 20h UT). The latter has particular problems from the almost full Moon, and rises less than an hour before dawn in either hemisphere anyway. Pegasids Active: July 7 - 13; Maximum: July 10 (lambda = 107.5deg); ZHR = 3; Radiant: alpha = 340deg, delta = +15deg, Radiant drift: see Table 3; Radius: 5deg; V = 70 km/s; r = 3.0; TFC: alpha = 320deg, delta = +10deg and alpha = 332deg, delta = +33deg (beta > 40deg N); alpha = 357deg, delta = +02deg (beta < 40deg N). Monitoring this short-lived minor shower is not easy, as a few cloudy nights mean its loss for visual observers, but with the Moon nearly new for its peak this year, everyone - particularly those in the northern hemisphere - should attempt to cover it. The shower is best-seen in the second half of the night, and the Moon will be only a slight distraction near dawn. The maximum ZHR is generally low, and swift, faint meteors can be expected. Telescopic observing would be especially useful. July Phoenicids Active: July 10 - 16; Maximum: July 13 (lambda = 111deg); ZHR = variable 3 - 10, usually <4; Radiant: alpha = 32deg, delta = -48deg, Radiant drift: see Table 3; Radius: 7deg; V = 47 km/s; r = 3.0; TFC: alpha = 041deg, delta = -39deg and alpha = 066deg, delta = -62deg (beta < 10deg N). This minor shower can be seen from the southern hemisphere, from where it only attains a reasonable elevation above the horizon after midnight. This is an ideal year to watch it, since new Moon falls perfectly for its expected peak. Activity can be quite variable visually, and indeed observations show it is a richer radio meteor source (possibly also telescopically too, but more results are needed). The peak has not been well-observed for some considerable time, though recent years have brought maximum ZHRs of under 4, when the winter weather has allowed any coverage at all. More data would be very welcome! Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [3/6] Привет всем! Вот, свалилось из Internet... Perseids Active: July 17 - August 24; Maxima: August 12, 23h UT (lambda = 139.81deg), August 13, 05h UT (lambda = 140.03deg) and August 13, 13h UT (lambda = 140.35deg); ZHR: primary peak = variable, recently ~120-160, secondary and tertiary peaks = 100; Radiant: alpha = 46deg, delta = +58deg, Radiant drift: see Table 3; Radius: 5deg; V = 59 km/s; r = 2.6; TFC: alpha = 019deg, delta = +38deg and alpha = 348deg, delta = +74deg before 02h local time; alpha = 043deg, delta = +38deg and alpha = 073deg, delta = +66deg after 02h local time (beta > 20deg N); PFC: alpha = 300deg, delta = +40deg, alpha = 000deg, delta = +20deg or alpha = 240deg, delta = +70deg (beta > 20deg N). The Perseids have become the single most exciting and dynamic meteor shower in recent times, with outbursts producing EZHRs of 400+ in 1991 and 1992, decreasing to around 300 in 1993, 220 in 1994 and ~120-160 since, at the shower's primary maximum. Allowing for an average annual shift of ~+0.05deg in lambda since 1991, this peak is expected to fall around 23h UT on August 12. Other timing variations cannot be ruled-out, however. A new feature in 1997 was a tertiary peak, of strength comparable to the traditional (currently secondary) maximum, but a few hours after it. The timing for this third peak is based on just this one return, but there are no guarantees it will recur in 1999. Even now, as the Perseids' parent comet, 109P/Swift- Tuttle, returns to the outer Solar System after its 1992 perihelion passage, the shower can still spring surprises! The August new Moon provides the perfect opening for all watchers, certainly. As the radiant rises throughout the night for the northern hemisphere, near and post-midnight watching is most valuable. If the maxima appear as predicted the places to be should be Europe; Eastern North America; Far Eastern Siberia, Alaska and the Northern Pacific Ocean, respectively. Visual and photographic observers should need little encouragement to cover this stream, but telescopic and video watching near the main peak would be valuable in confirming or clarifying the possibly multiple nature of the Perseid radiant, something not detectable visually. Radio data would naturally enable early confirmation, or detection, of perhaps otherwise unobserved maxima if the timings prove unsuitable for land-based sites. The only negative aspect to the shower is the impossibility of covering it from the bulk of the southern hemisphere. delta-Aurigids Active: September 5 - October 10; Maximum: September 9 (lambda = 166deg); ZHR = 6; Radiant: alpha = 60deg, delta = +47deg, Radiant drift: see Table 3; Radius: 5deg; V = 64 km/s; r = 3.0; TFC: alpha = 052deg, delta = +60deg; alpha = 043deg, delta = +39deg and alpha = 023deg, delta = +41deg (beta > 10deg S). An essentially northern hemisphere shower, badly in need of more observations. The delta-Aurigids are actually part of a series of showers with radiants in Aries, Perseus, Cassiopeia and Auriga, active from late August into October. They typically produce low rates of generally faint meteors, and have yet to be well-seen in more than an occasional year. Circumstances are perfect for their peak in 1999, with new Moon on September 9. Telescopic data to examine all the radiants in this region of sky - and possibly observe the telescopic beta-Cassiopeids simultaneously - would be especially useful, but photographs, video records and visual plotting would be welcomed too. The delta-Aurigid radiant is at a useful elevation from roughly 23h-00h onwards, so protracted watching is distinctly possible. October to December Ecliptical minor shower activity reaches what might be regarded as a peak in early to mid November, with the Taurid streams in action. Before then is a moonless Draconid epoch, together with badly Moon-affected epsilon-Geminid and Orionid maxima, all in October. The Orionids' central peak is likely around 20h UT on October 21 for radio observers. The Leonids in November may still be capable of producing high to storm activity this year, but the alpha-Monocerotids (November 22, 01h UT) are lost to the Moon. December's new Moon is excellent news for covering the chi-Orionids, Phoenicids, Puppid- Velids, Monocerotids and sigma-Hydrids, along with the Geminids. The downside is losing the Coma Berenicids and Ursids (peak due circa December 22, 23h UT) to full Moon. Draconids Active: October 6 - 10; Maximum: October 9, 03h UT (lambda = 195.4deg); ZHR = periodic, up to storm levels; Radiant: alpha = 262deg, delta = +54deg, Radiant drift: negligible; Radius: 5deg; V = 20 km/s; r = 2.6; TFC: alpha = 290deg, delta = +65deg and alpha = 288deg, delta = +39deg (beta > 30deg N). New Moon perfectly favours any Draconids that appear this year. Unfortunately for potential observers, although this periodic shower has produced spectacular, brief, meteor storms twice already this century, in 1933 and 1946, and lower rates in several other years (ZHRs ~20-200+), so far, detectable activity has only been seen in years when the stream's parent comet, 21P/Giacobini-Zinner, has returned to perihelion. It did this last in 1998 November. The peak time above is based on the Earth's closest approach to the comet orbit's node, but activity might be seen before or considerably after this too. The radiant is circumpolar from many locations, but is higher in the pre-midnight and near-dawn hours on October 8-10. The shower is only properly observable from the northern hemisphere. Taurids Southern Taurids Active: October 1 - November 25; Maximum: November 5 (lambda = 223deg); ZHR = 5; Radiant: alpha = 52deg, delta = +13deg, Radiant drift: see Table 3; Size: alpha = 20deg x delta = 10deg; V = 27 km/s; r = 2.3; TFC: Choose fields on the ecliptic and ~10deg E or W of the radiants (beta > 40deg S). Northern Taurids Active: October 1 - November 25; Maximum: November 12 (lambda = 230deg); ZHR = 5; Radiant: alpha = 58deg, delta = +22deg, Radiant drift: see Table 3; Size: alpha = 20deg x delta = 10deg; V = 29 km/s; r = 2.3; TFC: as Southern Taurids. These two streams forms a complex associated with Comet 2P/Encke. Defining their radiants is best achieved by careful visual or telescopic plotting, photography or video work, since they are large and diffuse. The brightness and relative slowness of many shower meteors makes them ideal targets for photography, while these factors coupled with low, steady combined Taurid rates makes them excellent targets for newcomers to practice their plotting techniques on. The activity of both streams produces an apparently plateau- like maximum for about ten days in early November, and the shower has a reputation for producing some superbly bright fireballs at times, although seemingly not in every year. In 1995, an impressive crop of brilliant Taurids occurred between late October and mid-November, for instance. New Moon on November 8 means the entire Taurid peak should be treated to dark skies in 1999. The near-ecliptic radiants for both shower branches mean all meteoricists can observe the streams. Northern hemisphere observers are somewhat better- placed, as here suitable radiant zenith distances persist for much of the late autumnal nights. Even in the southern hemisphere, a good 3-5 hours' watching around local midnight is possible with Taurus well above the horizon, however. Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [4/6] Привет всем! Вот, свалилось из Internet... Leonids Active: November 14 - 21; Maximum: November 17, 23h UT (lambda = 235.16deg); ZHR = 100+ (45 in 1996, ~150? in 1997), but may reach storm level in 1999; Radiant: alpha = 153deg, delta = +22deg, Radiant drift: see Table 3; Radius: 5deg; V = 71 km/s; r = 2.9; TFC: alpha = 140deg, delta = +35deg and alpha = 129deg, delta = +06deg (beta > 35deg N); or alpha = 156deg, delta = -03deg and alpha = 129deg, delta = +06deg (beta < 35deg N). PFC: before 00h local time alpha = 120deg, delta = +40deg (beta > 40deg N); before 04h local time alpha = 120deg, delta = +20deg and after 04h local time alpha = 160deg, delta = 00deg (beta > 00deg N); before 00h local time alpha = 120deg, delta = +10deg (beta > 40deg N); and alpha = 160deg, delta = -10deg (beta < 00deg N). The perihelion passage of the Leonids' parent comet, 55P/Tempel-Tuttle, in 1998 February means high to storm-level Leonid activity may occur in 1999. There are, of course, no guarantees that this will happen, but all observers must realise that even discovering the absence of any unusual Leonid activity would still be very valuable information - albeit not all that interesting to witness! Recent visual IMO International Leonid Watch and radio observations suggest a peak timing around lambda = 235.16deg is most likely, but another plausible time is when the Earth passes the node of the comet's orbit, at lambda = 235.25deg (1999 November 18, 01h UT). The radiant rises only around local midnight (or indeed afterwards south of the equator), by which time the waxing gibbous Moon will be setting. Either suggested peak timing would favour locations in Europe, North Africa, the Near and Middle East plus European Russia. Even a minor variation in the peak's occurrence could mean places east or west of this zone may see something of the shower's best too, however. Look out for further updates in the IMO's journal WGN after the 1998 return. All observing methods should be utilised to the full, especially photography and video if a storm manifests. chi-Orionids Active: November 26 - December 15; Maximum: December 2 (lambda = 250deg); ZHR = 3; Radiant: a = 82deg, delta = +23deg, Radiant drift: see Table 3; Radius: 8deg; V = 28 km/s; r = 3.0; TFC: alpha = 083deg, delta = +09deg and alpha = 080deg, delta = +24deg (beta > 30deg S). A weak visual stream, but moderately active telescopically. Some brighter meteors have been photographed too. The shower has at least a double radiant, but the southern branch has been rarely detected. The chi-Orionids may be a continuation of the ecliptic complex after the Taurids cease to be active. The radiant used here is a combined one, suitable for visual work, although telescopic or video observations should be better-able to determine the exact radiant structure. The waning crescent Moon should give few problems, as the radiant is well on display in both hemispheres throughout the night. Phoenicids Active: November 28 - December 9; Maximum: December 6, 20h UT (lambda = 254.25deg); ZHR = variable, usually 3 or less, may reach 100; Radiant: alpha = 18deg, delta = -53deg, Radiant drift: see Table 3; Radius: 5deg; V = 18 km/s; r = 2.8; TFC: alpha = 040deg, delta = -39deg and alpha = 065deg, delta = -62deg (beta < 10deg N). Only one impressive Phoenicid return has so far been reported, that of its discovery in 1956, when the ZHR was ~100. Three other potential bursts of lower activity have been reported, but never by more than one observer, under uncertain circumstances. Reliable IMO data shows recent activity to be virtually nonexistent. This may be a periodic shower, however, and more observations of it are needed by all methods. Radio workers may find difficulties, as radar echoes from the 1956 event were only 30 per hour, perhaps because these low-velocity meteors produce too little radio- reflecting ionization. Observing conditions this year are excellent for all southern hemisphere watchers, with new Moon on December 7. The radiant is well on view for most of the night, but culminates at dusk. Puppid-Velids Active: December 1 - 15; Maximum: December ~7 (lambda ~ 255deg); ZHR ~10; Radiant: alpha = 123deg, delta = -45deg, Radiant drift: see Table 3; Radius: 10deg; V = 40 km/s; r = 2.9; TFC: alpha = 090deg to 150deg, delta = -20deg to -60deg; choose pairs of fields separated by about 30deg in a, moving eastwards as the shower progresses (b < 10deg N). This is a very complex system of poorly-studied showers, visible chiefly to those south of the equator. Up to ten sub-streams have been identified, with radiants so tightly clustered, visual observing cannot readily separate them. Photographic, video or telescopic work would thus be sensible, or very careful visual plotting. The activity is so badly-known, we can only be reasonably sure that the highest rates occur in early to mid December, perfect for the new Moon period this year. Some of these showers may visible from late October to late January. Most shower meteors are quite faint, but occasional bright fireballs, notably around the suggested maximum here, have been reported previously. The radiant area is on-view all night, but is highest towards dawn. Monocerotids Active: November 27 - December 17; Maximum: December 9 (lambda = 257deg); ZHR = 3; Radiant: alpha = 100deg, delta = +08deg, Radiant drift: see Table 3; Radius: 5deg; V = 42 km/s; r = 3.0; TFC: alpha = 088deg, delta = +20deg and alpha = 135deg, delta = +48deg (beta > 40deg N); or alpha = 120deg, delta = -03deg and alpha = 084deg, delta = +10deg (b < 40deg N). Only low visual rates can be expected from this source, making accurate visual plotting, telescopic or video work essential, particularly because the meteors are normally faint. The shower details, even including the radiant position, are rather uncertain. Recent IMO data shows only weak signs of a maximum as indicated above. Telescopic data suggests a later maximum, around December 16 (lambda ~264deg) from a radiant at alpha = 117deg, delta = +20deg. This is a very good year for all meteor workers to make observations to help resolve these points, as the Moon is not a problem. The radiant is on-show nearly all night, culminating around 01h local time. sigma-Hydrids Active: December 3 - 15; Maximum: December 12 (lambda = 260deg); ZHR = 2; Radiant: alpha = 127deg, delta = +02deg, Radiant drift: see Table 3; Radius: 5deg; V = 58 km/s; r = 3.0; TFC: alpha = 095deg, delta = 00deg and alpha = 160deg, delta = 00deg (all sites, after midnight only). Although first detected in the 1960s by photography, sigma-Hydrids are typically swift and faint, and rates are generally very low, close to the visual detection threshold. Since their radiant, a little over 10deg east of the star Procyon (alpha Canis Minoris), is near the equator, all observers can cover this shower. The radiant rises in the late evening hours, but is best viewed after local midnight. This means the waxing crescent Moon will have set long before sigma-Hydrid watching can begin at their peak in 1999. Recent data indicates the peak may occur up to six days earlier than suggested above, and would benefit from visual plotting, telescopic or video work to pin it down more accurately. Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [5/6] Привет всем! Вот, свалилось из Internet... Geminids Active: December 7 - 17; Maximum: December 14, 11h UT (lambda = 262.0deg); ZHR = 120; Radiant: alpha = 112deg, delta = +33deg, Radiant drift: see Table 3; Radius: 5deg; V = 35 km/s; r = 2.6; TFC: alpha = 087deg, delta = +20deg and alpha = 135deg, delta = +49deg before 23h local time, alpha = 087deg, delta = +20deg and alpha = 129deg, delta = +20deg after 23h local time (beta > 40yN); alpha = 120deg, delta = -03deg and alpha = 084deg, delta = +10deg (beta < 40deg N). PFC: alpha = 150deg, delta = +20deg and alpha = 060deg, delta = +40deg (beta > 20deg N); alpha = 135deg, delta = -05deg and alpha = 080deg, delta = 00deg (beta < 20deg N). One of the finest annual showers presently observable. The waxing crescent Moon will have set by about 22h-23h local time at their peak, so much of the second half of the night at least will be available for observing them. Well north of the equator, their radiant rises around sunset, and is at a usable elevation from the local evening hours onwards. In the southern hemisphere, the radiant appears only around local midnight or so. Even here, this is a splendid stream of often bright, medium-speed meteors, a rewarding sight for all watchers. The peak has shown slight signs of variability in its maximum rates and the actual peak timing, so the best activity may occur a little before or, more likely, after, the suggested time above, perhaps up to 15h-16h UT. This means North American to Far Eastern sites are most likely to see the best from the 1999 Geminids. Some mass-sorting within the stream means the fainter telescopic meteors should be most abundant almost 1deg of solar longitude ahead of the visual maximum, with telescopic results indicating these meteors radiate from an elongated region, perhaps with three sub-centers. Further results on this topic would be useful, but all methods can be employed to observe the shower. Abbreviations alpha, delta: Coordinates for a shower's radiant position, usually at maximum. alpha is right ascension, delta is declination. Radiants drift across the sky each day due to the Earth's own orbital motion around the Sun, and this must be allowed for using the details in Table 3 for nights away from the listed shower maxima. r: The population index, a term computed from each shower's meteor magnitude distribution. r = 2.0 - 2.5 is brighter than average, while r above 3.0 is fainter than average. lambda: Solar longitude, a precise measure of the Earth's position on its orbit which is not dependent on the vagaries of the calendar. All lambda are given for the equinox 2000.0. V: Atmospheric or apparent meteoric velocity given in km/s. Velocities range from about 11 km/s (very slow) to 72 km/s (very fast). 40 km/s is roughly medium speed. ZHR: Zenithal Hourly Rate, a calculated maximum number of meteors an ideal observer would see in perfectly clear skies with the shower radiant overhead. This figure is given in terms of meteors per hour. Where meteor activity persisted at a high level for less than an hour, or where observing circumstances were very poor, an estimated ZHR (EZHR) is used, which is less accurate than the normal ZHR. TFC and PFC: Suggested telescopic and small-camera photographic field centers respectively. beta is the observer's latitude ("<" means "south of" and ">" means "north of"). Pairs of telescopic fields must be observed, alternating about every half hour, so that the positions of radiants can be defined. The exact choice of TFC or PFC depends on the observer's location and the elevation of the radiant. Note that the TFCs are also useful centers to use for video camera fields as well. Table 1. Lunar phases for 1999. New Moon First Quarter Full Moon Last Quarter January 02 January 09 January 17 January 24 January 31 February 08 February 16 February 23 March 02 March 10 March 17 March 24 March 31 April 09 April 16 April 22 April 30 May 08 May 15 May 22 May 30 June 07 June 13 June 20 June 28 July 06 July 13 July 20 July 28 August 04 August 11 August 19 August 26 September 02 September 09 September 17 September 25 October 02 October 09 October 17 October 24 October 31 November 08 November 16 November 23 November 29 December 07 December 16 December 22 December 29 Table 2: Working list of visual meteor showers. Details in this Table were correct according to the best information available in June 1998. Contact the IMO's Visual Commission for more information. Maximum dates in parentheses indicate reference dates for the radiant, not true maxima. Some showers have ZHRs that vary from year to year. The most recent reliable figure is given here, except for possibly periodic showers that are noted as "var." = variable. Activity Maximum Radiant Shower Period Date lambda alpha delta [deg] [deg] [deg] Quadrantids Jan 01-Jan 05 Jan 03 283.16 230 +49 delta-Cancrids Jan 01-Jan 24 Jan 17 297 130 +20 alpha-Centaurids Jan 28-Feb 21 Feb 08 319.2 210 -59 delta-Leonids Feb 15-Mar 10 Feb 25 336 168 +16 gamma-Normids Feb 25-Mar 22 Mar 14 353 249 -51 Virginids Jan 25-Apr 15 (Mar 25)(004) 195 -04 Lyrids Apr 16-Apr 25 Apr 22 032.1 271 +34 pi-Puppids Apr 15-Apr 28 Apr 24 033.5 110 -45 eta-Aquarids Apr 19-May 28 May 06 045.5 338 -01 Sagittarids Apr 15-Jul 15 (May 20)(059) 247 -22 Pegasids Jul 07-Jul 13 Jul 10 107.5 340 +15 July Phoenicids Jul 10-Jul 16 Jul 13 111 032 -48 Piscis Austrinids Jul 15-Aug 10 Jul 28 125 341 -30 Southern delta-Aquarids Jul 12-Aug 19 Jul 28 125 339 -16 alpha-Capricornids Jul 03-Aug 15 Jul 30 127 307 -10 Southern iota-Aquarids Jul 25-Aug 15 Aug 04 132 334 -15 Northern delta-Aquarids Jul 15-Aug 25 Aug 09 136 335 -05 Perseids Jul 17-Aug 24 Aug 12 140.0 046 +58 kappa-Cygnids Aug 03-Aug 25 Aug 18 145 286 +59 Northern iota-Aquarids Aug 11-Aug 31 Aug 20 147 327 -06 alpha-Aurigids Aug 25-Sep 05 Sep 01 158.6 084 +42 delta-Aurigids Sep 05-Oct 10 Sep 09 166 060 +47 Piscids Sep 01-Sep 30 Sep 20 177 005 -01 Draconids Oct 06-Oct 10 Oct 09 195.4 262 +54 epsilon-Geminids Oct 14-Oct 27 Oct 18 205 102 +27 Orionids Oct 02-Nov 07 Oct 21 208 095 +16 Southern Taurids Oct 01-Nov 25 Nov 05 223 052 +13 Northern Taurids Oct 01-Nov 25 Nov 12 230 058 +22 Leonids Nov 14-Nov 21 Nov 17 235.16 153 +22 alpha-Monocerotids Nov 15-Nov 25 Nov 22 239.32 117 +01 chi-Orionids Nov 26-Dec 15 Dec 02 250 082 +23 Phoenicids Nov 28-Dec 09 Dec 06 254.25 018 -53 Puppid-Velids Dec 01-Dec 15 (Dec 07)(255) 123 -45 Monocerotids Nov 27-Dec 17 Dec 09 257 100 +08 sigma-Hydrids Dec 03-Dec 15 Dec 12 260 127 +02 Geminids Dec 07-Dec 17 Dec 14 262 112 +33 Coma Berenicids Dec 12-Jan 23 Dec 20 268 175 +25 Ursids Dec 17-Dec 26 Dec 22 270.7 217 +76 Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: IMO 1999 Meteor Shower Calendar [6/6] Привет всем! Вот, свалилось из Internet... Shower v r ZHR Code [km/s] Quadrantids 41 2.1 120 QUA delta-Cancrids 28 3.0 4 DCA alpha-Centaurids 56 2.0 6 ACE delta-Leonids 23 3.0 2 DLE gamma-Normids 56 2.4 8 GNO Virginids 30 3.0 5 VIR Lyrids 49 2.9 15 LYR pi-Puppids 18 2.0 var. PPU eta-Aquarids 66 2.7 60 ETA Sagittarids 30 2.5 5 SAG Pegasids 70 3.0 3 JPE July Phoenicids 47 3.0 var. PHE Piscis Austrinids 35 3.2 5 PAU Southern delta-Aquarids 41 3.2 20 SDA alpha-Capricornids 23 2.5 4 CAP Southern iota-Aquarids 34 2.9 2 SIA Northern delta-Aquarids 42 3.4 4 NDA Perseids 59 2.6 140 PER kappa-Cygnids 25 3.0 3 KCG Northern iota-Aquarids 31 3.2 3 NIA alpha-Aurigids 66 2.5 10 AUR delta-Aurigids 64 3.0 6 DAU Piscids 26 3.0 3 SPI Draconids 20 2.6 var. GIA epsilon-Geminids 70 3.0 2 EGE Orionids 66 2.9 20 ORI Southern Taurids 27 2.3 5 STA Northern Taurids 29 2.3 5 NTA Leonids 71 2.5 100+ LEO alpha-Monocerotids 65 2.4 var. AMO chi-Orionids 28 3.0 3 XOR Phoenicids 18 2.8 var. PHO Puppid-Velids 40 2.9 10 PUP Monocerotids 42 3.0 3 MON sigma-Hydrids 58 3.0 2 HYD Geminids 35 2.6 120 GEM Coma Berenicids 65 3.0 5 COM Ursids 33 3.0 10 URS Table 4. Working list of daytime radio meteor streams. The "Best Observed" columns give the approximate local mean times between which a four-element antenna at an elevation of 45deg receiving a signal from a 30-kW transmitter 1000 km away should record at least 85% of any suitably positioned radio-reflecting meteor trails for the appropriate latitudes. Note that this is often heavily dependent on the compass direction in which the antenna is pointing, however, and applies only to dates near the shower's maximum. Shower Activity Max lambda Radiant Best Observed Rate Date 2000.0 alp.del. 50 N 35 S Cap/Sagittarids Jan 13-Feb 04 Feb 01 312.5 299 -15 11h-14h 09h-14h medium chi-Capricornids Jan 29-Feb 28 Feb 13 324.7 315 -24 10h-13h 08h-15h low Piscids (Apr.) Apr 08-Apr 29 Apr 20 030.3 007 +7 07h-14h 08h-13h low delta-Piscids Apr 24-Apr 24 Apr 24 034.2 011 +12 07h-14h 08h-13h low epsilon-Arietids Apr 24-May 27 May 09 048.7 044 +21 08h-15h 10h-14h low Arietids (May) May 04-Jun 06 May 16 055.5 037 +18 08h-15h 09h-13h low o-Cetids May 05-Jun 02 May 20 059.3 028 -4 07h-13h 07h-13h medium Arietids May 22-Jul 02 Jun 07 076.7 044 +24 06h-14h 08h-12h high zeta-Perseids May 20-Jul 05 Jun 09 078.6 062 +23 07h-15h 09h-13h high beta-Taurids Jun 05-Jul 17 Jun 28 096.7 086 +19 08h-15h 09h-13h medium gamma-Leonids Aug 14-Sep 12 Aug 25 152.2 155 +20 08h-16h 10h-14h low Sextantids Sep 09-Oct 09 Sep 27 184.3 152 0 06h-12h 06h-13h medium Useful addresses For more information on observing techniques, and when submitting results, please contact the appropriate IMO Commission Director: Fireball Data Center (FIDAC): A. Knoefel, Saarbruecker Strasse 8, D-40476 Duesseldorf, Germany. e-mail: fidac@imo.net Photographic Commission: M. de Lignie, Prins Hendrikplein 42, NL-2264 SN Leidschendam, The Netherlands. e-mail: photo@imo.net Radio Commission: Temporarily vacant. e-mail: radio@imo.net Telescopic Commission: M. Currie, 25 Collett Way, Grove, Wantage, Oxon. OX12 0NT, UK. e-mail: tele@imo.net Visual Commission: R. Arlt, Friedenstrasse 5, D-14109 Potsdam, Germany. email: visual@imo.net or contact IMO's Homepage on the World-Wide-Web: http://www.imo.net/ For further details on IMO membership, please write to: Ina Rendtel, IMO Treasurer, Mehlbeerenweg 5, D-14469 Potsdam, Germany. e-mail: treasurer@imo.net Please try to enclose return postage when writing to any IMO officials, either in the form of stamps (same country only) or as an International Reply Coupon (I.R.C. - available from main postal outlets). Thank you! Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Sky & Telescope News Bulletin - July 3, 1998 Привет всем! Вот, свалилось из Internet... SKY & TELESCOPE NEWS BULLETIN JULY 3, 1998 SOHO STILL AWOL No news is definitely *not* good news for handlers of the Solar and Heliospheric Observatory, which has been incommunicado since June 25th. Mission engineers suspect that the spacecraft began slowly spinning such that its solar panels were no longer exposed much to sunlight, which caused the spacecraft to lose power. However, there is some hope that in a few weeks the craft's orbital motion around the Sun will change this geometry and allow enough sunlight on the panels to charge SOHO's batteries. In the meantime, a joint NASA/ESA inquiry board has been formed to review the incident. More information, images, and status reports can be found at http://sohowww.nascom.nasa.gov. TARGET TURKMENISTAN We've received word that on June 20th a hefty meteorite fell about 100 km from the city of Tashauz in Turkmenistan. According to scientist Seid Muhamednazarov, the daylight fall was preceded by a dazzling orange bolide that left a train of black smoke as it moved northeast across the sky. The projectile broke into at least three pieces before impact, and the largest fragment created a small crater about 6 meters wide and 4 deep. At its bottom a recovery team found a cone-shaped stony iron meteorite weighing between 300 and 500 kg. ASTRONAUTS VISIT AXAF CENTER The five-member crew of Space Shuttle mission STS 93 paid a courtesy call in Cambridge, Massachusetts, last week. On June 25th the astronauts flew in from Houston to visit the AXAF Science Center, which will serve as the focus of research with the Advanced X-ray Astrophysics Facility. During their brief stay commander Eileen Collins and her four crewmates met the center's staff and answered questions about their upcoming deployment flight. The launch of AXAF had been planned for late August, but delays have pushed that to next January 21st. Collins stands to become the first woman to command a shuttle mission. Joining her aboard *Columbia* will be Jeff Ashby, Cady Coleman, and French astronaut Michel Tognini. Also aboard will be astronomer-astronaut Steve Hawley, whose four previous shuttle flights include the launch of the Hubble Space Telescope and one of the subsequent HST refurbishment missions. PATHFINDER's ASTEROIDS It was one year ago this week that NASA's Mars Pathfinder thumped onto the dusty surface of Mars. Recently, four asteroids were named to recognize key members of the Mars Pathfinder team. Eleanor F. Helin, who discovered the asteroids, announced the namings during a June 10th ceremony at the Jet Propulsion Laboratory in Pasadena, California. The four honorees are Donna L. Shirley (for rover design), Matthew P. Golombek (project scientist), and Anthony J. Spear and Brian K. Muirhead (project managers). All four namesakes are modest, main-belt objects; 5624 Shirley is the largest, perhaps 20 km, while 6456 Golombek, 6487 Tonyspear, and 7818 Muirhead have pronounced orbital eccentricities that carry them near or inside the orbit of Mars. THIS WEEK'S "SKY AT A GLANCE" Some daily events in the changing sky, from the editors of SKY & TELESCOPE. JULY 5 -- SUNDAY * The waxing gibbous Moon shines above the orange star Antares tonight and tomorrow. JULY 6 -- MONDAY * The red long-period variable stars RT Sagittarii, RR Scorpii, and R Aquilae should be at their maximum brightnesses (6th or 7th magnitude) this week. JULY 7 -- TUESDAY * Venus shines a fraction of a degree from the 4.6-magnitude star Iota Tauri during dawn Wednesday morning. Take a look with binoculars or a telescope. They're separated by only 0.2<dg> or 0.3<dg> as seen from eastern North America, and 0.1<dg> at the time of dawn for the West Coast. JULY 8 -- WEDNESDAY * Look to the lower right of the nearly full Moon this evening for the Teapot asterism of Sagittarius. JULY 9 -- THURSDAY * Full Moon (12:01 p.m. Eastern Daylight Time). JULY 10 -- FRIDAY * Look high in the northwest after dark for the Big Dipper. It's hanging bowl down. Follow the curve of its handle around to the left to locate Arcturus, the brightest star shining high in the west. Far below Arcturus and a bit left is slightly fainter Spica. JULY 11 -- SATURDAY * Vega is the brightest star shining high in the east after dark. Compare its pale blue-white tint to the pale yellow-orange of Arcturus, which is shining equally brightly high in the west. THIS WEEK'S PLANET ROUNDUP MERCURY glimmers in the evening twilight. Look for it very low in the west-northwest about 45 minutes after sunset. It's far to the lower right of the star Regulus. VENUS shines brightly (magnitude -3.9) low in the east-northeast during dawn. MARS is barely emerging from the glow of sunrise. It's faint and still very low. Scan for it far to the lower left of Venus. JUPITER rises around midnight daylight saving time. It's the brilliant "star" (magnitude -2.6) climbing up the southeastern sky during the early morning hours. SATURN rises around 1:30 a.m. It's the dimmer "star" (magnitude +0.3) well to Jupiter's lower left before and during dawn. URANUS and NEPTUNE, magnitudes 5.7 and 7.8 respectively, are in Capricornus in the south during early-morning hours. You'll need binoculars or a small telescope. See the finder chart in the May Sky & Telescope, page 96. PLUTO, magnitude 13.7, is near the Ophiuchus-Scorpius border in the south after dark. See the finder chart in the May Sky & Telescope, page 97. The charts for Uranus, Neptune, and Pluto are also at http://www.skypub.com/whatsup/urnepl98.html. (All descriptions that relate to the horizon or zenith are written for the world's midnorthern latitudes. Descriptions that also depend on longitude are for North America. Eastern Daylight Time, EDT, equals Universal Time minus 4 hours.) More details, sky maps, and news of other celestial events appear each month in SKY & TELESCOPE, the essential magazine of astronomy. See our enormous Web site at http://www.skypub.com/. Clear skies! Copyright 1998 Sky Publishing Corporation. S&T's Weekly News Bulletin and Sky at a Glance stargazing calendar are provided as a service to the astronomical community by the editors of SKY & TELESCOPE magazine. Widespread electronic distribution is encouraged as long as these paragraphs are included. But the text of the bulletin and calendar may not be published in any other form without permission from Sky Publishing (contact permissions@skypub.com or phone 617-864-7360). Illustrated versions, including active links to related Internet resources, are available via SKY Online on the World Wide Web at http://www.skypub.com/. In response to numerous requests, and in cooperation with the Astronomical League (http://www.mcs.net/~bstevens/al/) and the American Association of Amateur Astronomers (http://www.corvus.com/), S&T's Weekly News Bulletin and Sky at a Glance are available via electronic mailing list too. For a free subscription, send e-mail to skyline@gs1.revnet.com and put the word "join" on the first line of the body of the message. To unsubscribe, send e-mail to skyline@gs1.revnet.com and put the word "unjoin" on the first line of the body of the message. SKY & TELESCOPE, the Essential Magazine of Astronomy, is read by more than 200,000 enthusiasts each month. It is available on newsstands worldwide. For subscription information, or for a free copy of our catalog of fine astronomy books and products, please contact Sky Publishing Corp., P.O. Box 9111, Belmont, MA 02478-9111, U.S.A. Phone: 800-253-0245 (U.S. and Canada); 617-864-7360 (International). Fax: 617-864-6117. E-mail: custserv@skypub.com. SKY Online: http://www.skypub.com/. Clear skies! Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Galileo Spacecraft Sees Volcanic Fireworks On Jupiter's Moon Io Привет всем! Вот, свалилось из Internet... Note: New images of Io taken by the Galileo spacecraft are available on the Galileo home page: http://www.jpl.nasa.gov/galileo/ MEDIA RELATIONS OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011 http://www.jpl.nasa.gov Contact: Jane Platt FOR IMMEDIATE RELEASE July 2, 1998 GALILEO SPACECRAFT SEES VOLCANIC FIREWORKS ON JUPITER'S MOON IO New observations by NASA's Galileo spacecraft reveal dozens of volcanic vents on Jupiter's fiery moon Io where lava sizzles hotter than any surface temperatures recorded on any planetary body in our solar system. Temperatures this high are not known to have occurred on Earth for billions of years. At one such volcanic vent, known as Pillan Patera, two of Galileo's instruments have indicated the lava temperature may be 2,000 Kelvin (3,140 degrees Fahrenheit). These results are reported in the July 3 issue of the journal Science. "The most likely explanation for these very high temperatures is that the eruptions contain magnesium-rich silicates," said Dr. Alfred McEwen of the University of Arizona, Tucson, AZ, a member of Galileo's solid state imaging camera team. "We've tentatively identified magnesium-rich orthopyroxene in lava flows around these hot spots. This leads us to conclude that silicate volcanism is taking place with lava compositions expected to melt at a very high temperature. We must now think of Io's volcanoes in terms of the type of very high-temperature silicate volcanism which was found on Earth during its early days, and which we suspect occurred also on Venus and Mars." The new findings by the Galileo camera and the spacecraft's near infrared mapping spectrometer have updated scientists' information on Io's volcanic processes. Previously, Io observations made by the Voyager spacecraft in 1979 put the highest temperature estimates at about 650 Kelvin (710 degrees Fahrenheit). This led many scientists to believe that Io's volcanic activity was caused by low-temperature sulfur volcanism. In 1986, ground-based telescope observations increased the temperature estimates to above 900 Kelvin (1,160 degrees Fahrenheit), which suggested that silicate volcanism was occurring at least occasionally, just as it does on Earth today. In 1996 and 1997, Galileo identified 30 locations with temperatures higher than 700 Kelvin (800 degrees Fahrenheit). "This new data indicate that high-temperature eruptions on Io are a basic and common part of its active volcanic processes," said Dr. Torrence Johnson of JPL, Galileo project scientist. Johnson led the group that found the high temperature eruption in 1986. He is also a member of the near infrared mapping spectrometer team. "Io's current volcanic activity may have a lot in common with ancient volcanic processes on Earth and other planets. Since the geologic record from those times is very sparse, it's quite exciting to be able to study this type of volcanism going on today." "This discovery of high-temperature silicate volcanism provides us with an extremely important clue to understanding the geophysical processes within Io," McEwen explained. Io is heated by periodic tides as it orbits Jupiter, along with the other Galilean satellites (Europa, Ganymede and Callisto). Armed with this new information, scientists also hope to learn more about the composition of Io's crust. "Io's extreme volcanic activity is expected to result in a low-density crust rich in silica, sodium and potassium," said McEwen. "However, the high-temperature volcanism suggests that the crust may be composed of heavier lavas." Galileo's solid state imaging camera observed Io during 11 eclipses in 5 orbits, when Io was in Jupiter's shadow, and sunlight was blocked so the camera could better see the glowing volcanic vents. Io's hot spots were also studied by the spacecraft's near infrared mapping spectrometer during 11 orbits, mostly when Io was not in eclipse. The camera provides high spatial resolution to image the hottest features and map color variations, while the spectrometer can observe at many wavelengths and is sensitive to a wider temperature range. Thus, the combination of both instruments provides a powerful means to study Io's volcanism. The camera and spectrometer together have discovered a total of 41 hot spots on Io. Scientists hope to gather more detailed information about Io with two planned close flybys in late 1999, as long as the Galileo spacecraft remains healthy. Galileo has been orbiting Jupiter and its four largest moons, including Io, for 2-1/2 years. It is currently in the midst of an extended journey, known as the Galileo Europa Mission, with eight flybys of Europa and four of Callisto, in addition to the Io flybys. Galileo Europa Mission is managed by JPL, a division of California Institute of Technology, Pasadena, CA. Additional information and images taken by the Galileo spacecraft are available on the Internet at http://www.jpl.nasa.gov/galileo . Images are also available at http://photojournal.jpl.nasa.gov . ##### Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: Galileo Data Sets From First Eight Orbits Now Available Привет всем! Вот, свалилось из Internet... Galileo Solid State Imaging Full Data Releases ALL IMAGES obtained by the Galileo Solid State Imaging (SSI) system during the spacecraft's first eight orbits (G1, G2, C3, E4, E6, G7, G8) of Jupiter are now validated and available. Images and data obtained by NASA/JPL's Galileo mission have been available on an ongoing basis during the spacecraft's journey through the Jovian system in order to share with the public the excitement of exploration and new discoveries being made via the NASA/JPL Galileo spacecraft. Galileo scientists have a one year period set aside for the process of calibrating and validating the data. The full digital images necessary for scientific analysis are released within one year of receipt of an orbit's last data. ALL IMAGING DATA from Orbits one through eight is available via the Planetary Data System (PDS) Imaging Node For Galileo SSI data, go to URL: http://www-pdsimage.jpl.nasa.gov/PDS/public/Atlas/Atlas.html and select the option: "Galileo SSI REDRs of Earth and the Moon, Venus, Gaspra, Ida, and Jupiter and its satellites " The PDS homepage is: http://www-pdsimage.jpl.nasa.gov/PDS/ The PDS offers a simple query interface to access all fully released SSI data. It allows the user to search by various parameters such as target name, spacecraft clock, latitude/longitude, filter, phase angle, exposure, gain, and compression ratio. PDS will continue to expand and improve this interface which will eventually include a format to select data via a map interface. To accomodate the various needs of the scientific community, the archived files are raw data files which merge the multiple downlinks of data to provide the best final version of an image. Supporting data such as calibration files are also available. Such files include dark currents, radiometric calibrations, blemishes, hot pixels, etc.. Galileo Nominal Mission (6/96-12/97) Solid State Imaging Orbital Data Sets Public Release Schedule Orbit 1 (G1) September 06, 1997 Orbit 2 (G2) November 04, 1997 Orbit 3 (C3) December 19, 1997 Orbit 4 (E4) February 20, 1998 Orbit 6 (E6) April 05, 1998 Orbit 7 (G7) May 07, 1998 Orbit 8 (G8) June 25, 1998 Orbit 9 (C9) September 17, 1998 Orbit 10 (C10) November 06, 1998 Orbit 11 (E11) & GEM Schedules will be posted when available. Hа сегодня все, пока! =SANA=

Дата: 06 июля 1998 (1998-07-06) От: Alexander Bondugin Тема: NASA Instruments On Japanese Planet-B Spacecraft Will Aid Studies Of M Subject: NASA Instruments On Japanese Planet-B Spacecraft Will Aid Studies Of M Привет всем! Вот, свалилось из Internet... Douglas Isbell Headquarters, Washington, DC July 1, 1998 (Phone: 202/358-1753) Cynthia O'Carroll Goddard Space Flight Center, Greenbelt, MD (Phone: 301/286-6943) Dr. Yasunori Matogawa Institute of Space and Astronautical Science (ISAS) of Japan (Phone: 81-994-67-2211) RELEASE: 98-119 NASA INSTRUMENTS ON JAPANESE PLANET-B SPACECRAFT WILL AID STUDIES OF MARTIAN UPPER ATMOSPHERE A NASA instrument to measure the gas composition of the upper atmosphere of Mars and hardware to support a radio science experiment will fly on a Japanese spacecraft known as Planet-B. The Neutral Mass Spectrometer (NMS) instrument and Ultra Stable Oscillator are scheduled for launch aboard Planet-B on July 3, 1998, from the Kagoshima Space Center on Kyushu Island, Japan. "The Neutral Mass Spectrometer will enable us to measure the chemical composition of the upper atmosphere of Mars on a global scale, which has never been done before," said Dr. Hasso B. Niemann, the NMS principal investigator at NASA's Goddard Space Flight Center's Laboratory for Atmospheres in Greenbelt, MD. Previous upper atmospheric composition measurements were done in only two locations as NASA's Viking landers entered the Martian atmosphere on July 20 and Sept. 3, 1976, respectively. The radio science hardware was built by the Johns Hopkins University Applied Physics Laboratory in Laurel, MD, under contract to NASA. The ultra-precise signals generated by the oscillator serve as a very accurate clock to enable analysis of the Martian atmosphere and to help guide the spacecraft as it orbits the red planet. Planet-B is designed to perform long-term studies of the upper Martian atmosphere and ionosphere, and its interaction with the solar wind. Launch of Planet-B is scheduled for 2:12 p.m. EDT on July 3. After launch, the Planet-B spacecraft will be placed into Earth orbit and will use two swingbys past the Moon to establish conditions for a final trajectory to Mars. Once the spacecraft reaches Mars, which is now scheduled for Oct. 11, 1999, it will be placed into a highly elliptical or "egg- shaped" orbit stretching from 93-186 miles (150-300 kilometers) to about 17,000 miles (27,300 kilometers) above the surface. The low-altitude portion of the orbit will be used for remote sensing of the lower atmosphere and surface, and for direct measurements of upper atmosphere and ionosphere. The more distant parts of the orbit will allow instruments to probe the ions and neutral gas escaping from Mars, which interact with the charged-particle "wind" blowing outward from the Sun. Ionization of the upper atmospheric gas by solar radiation produces the charged-particle atmosphere (ionosphere) that acts as an obstacle to the solar wind. This radiation produces species of gas not seen in Mars' lower atmosphere, such as nitric oxide, or dissociates the atmosphere into single atomic species, such as atomic oxygen. If these neutral or ionized species possess enough energy, they can escape the gravitational pull of Mars, resulting in a net atmospheric loss. Measurements of lighter species such as atomic hydrogen and deuterium also can provide clues about the evolution of the Martian atmosphere. Mars has little or no intrinsic magnetic field to interact with this process, making it more like Venus in this respect than Earth. The upper atmosphere of Venus and its solar wind environment were studied for almost 14 years by the U. S. Pioneer Venus Orbiter spacecraft from a similar, highly elliptical orbit. The Planet-B NMS instrument is a state-of-the-art enhancement of the Pioneer Venus mass spectrometer, weighing only six pounds (2.8 kilograms). To conserve space and weight, electronic items such as transistors and integrated circuits were removed from their outer casings and placed in larger packages called hybrid circuits. Data from previous Mars exploration spacecraft such as Mariner 9 indicate that dust storms near the surface can heat the lower atmosphere and increase the gas density in the upper atmosphere where Planet-B will make its measurements. The U.S. Mars Surveyor 1998 mission known as the Mars Climate Orbiter, due for launch this December, carries an instrument called the Pressure Modulated Infrared Radiometer, which will provide complementary information on the lower atmosphere and its response to dust storms. The Planet-B project is managed by the Institute of Space and Astronautical Science (ISAS) within the Japanese Ministry of Education. Planet-B carries 14 instruments from Japan, Canada, Sweden, Germany and the United States. ISAS personnel will operate the spacecraft and its instruments. The spacecraft was built by the Nippon Electric Corporation and will be launched by the new M-5 rocket. This rocket is designed to expand Japan's launch capability for the inner planets and beyond. Further information on the NASA portion of the Planet-B mission and related graphics can be obtained via the Internet at the following URL: http://webserver.gsfc.nasa.gov/Code915/planetb.html -end- Hа сегодня все, пока! =SANA=

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