The redshift distance modulus modz , in mag, is derived from the Virgo infall vvir , it can be used to determine the absolute magnitude knowing the apparent one. It is defined as modz = 5 log(D L ) + 25 where D L is the luminosity-distance in Mpc, defined by the law of dimming of the observed flux: F L / D L 2 . ... D L is derived from the cosmological redshift, assuming the following values for the Hubble constant and other cosmological parameters: H 0 = 70 km/s/Mpc . ...

. This illustration provides a comparison for how big the moons of Mars appear to be, as seen from the surface of Mars, in relation to the size that Earth's moon appears to be when seen from the surface of Earth. Earth's moon actually has a diameter more than 100 times greater than the larger martian moon, Phobos. However, the martian moons orbit much closer to their planet than the distance between Earth and Earth's moon. // NASA/JPL-Caltech/Malin Space Science Systems/Texas A Univ.

... LVHIS Homepage . LVHIS Galaxies . AM0319-662 . ... Project C1341: ATCA EW367-m array (beam = 112.9" x 103.9", natural weighting), . observed 03-06-2005, reduced 03-06-2005 . ... The ATCA HI moment maps (below) show a large volume, about 40' x 40' in RA,DEC (not primary beam corrected for display purposes) and over a velocity range from 180 to 640 km/s. The velocity field shows that some of the extended gas clouds are in the foreground, most likely part of the Magellanic Stream. ...

... The crucial problem that limits our knowledge of our own galaxy, and prevents us from working out how and when it formed, is our inability to measure direct distances to distant stars, and to determine their proper motions. If we could get accurate parallaxes and proper motions for every star in the galaxy, we'd have things completely wrapped up, and surely we'd be able to figure out galaxy formation. ... Luckily, this is just what should be achievable using space interferometers. ...

... After all we cannot send a probe to the star Altair to confirm that it is 17 light years away. ... The "Bessel determined that the star 61 Cygni was about ten light years away" Earth goes around the Sun in one year, so in six month it is in the opposite position in its orbit. ... In 1838 Bessel determined that the star 61 Cygni had a parallax of 0.314 arcseconds and therefore the star was about ten light years away (today the distance is more precisely measured to be 11.4 light years). ...

Method of estimating distances to X­ray pulsars and their magnetic fields S.B. Popov Sternberg Astronomical Institute 119899, Russia, Moscow, Universitetski pr. 13 e­mail: polar@xray.sai.msu.su Abstract We suggest a new method of estimating distances to X­ray pulsars and their magnetic fields. ... Es­ timates of the distance: approximately 6 kpc, and the magnetic momentum: approximately 4 \Delta 10 31 G \Delta cm 3 , are obtained. ... Solid curve: d = 4 kpc, Ї = 37:6 \Delta 10 30 G \Delta cm 3 . ...

... Bad Astronomy . ... Mad Science . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... How did early astronomers determine the distance form earth to the sun, and what method is used today to determine distances in space? ... Since Huygens knew the Sun-Venus-Earth angle (from the phases), and he could directly measure the Sun-Earth-Venus angle (simply by measuring Venus' apparent distance from the Sun on the sky) all he needed was to know the distance from Earth to Venus. ...

... 2014 Irkutsk-Listvyanka, Russia G r o u p language English Theoretical round General note. ... Footstep of babr. Babr is a local representative of the biological family of cats (felidae) depicted on the coat of arms of Irkutsk, and the emblem of the X APAO (with a telescope in his mouth). ... Orion's Belt. The Babr decided to join company of astronomy animals-observers and came to Listvyanka to the X APAO to take photos of stars of Orion's Belt near the horizon. ... ISS in Zenith. ...

Lecture 15 Plan for Lecture Will complete derivation of Angular Diameter Distance and then go through a specific example-- Einstein de Sitter universe Then look at what it becomes in a ` flat ' universe (currently favoured) Then discuss velocities and the Hubble Law (actually derive this) And then specific examples of what the data on Luminosity distance seems to be saying about the dynamics of the universe Finally, a new topic -- horizons, in ... Also, k = 0 (for EdS) S () . ...

. Computer Ephemeris. Lunar equatorial positions. Explanations. Each row contains at 0 h and 12 h of Time Dynamical Terrestrial: month, day, apparent right ascension (hours, minutes, seconds), apparent declination (degrees, minutes, seconds of arc) and geocentric distance (in Earth's radii).

... Accurate identification of physical binary star systems has become of increasing interest in recent years. ... Identification of physical binary star systems, with an estimated reliability of such identifications based on the theory of probability, is also important for current and future efforts to find binary star systems that are candidates for observations with the aim of determining their orbits and component masses. ... probability of the proximity of proper motions and ; . ...

... Д. л. кДлнйкЙмЦЗ еУТНУ,ТНЛИ ,,УТЫ ТЪ,ВММњИ ЫМЛ,В ТЛЪВЪ ЛП. е.З. гУПУМУТУ, унй нДдйЦ "тдДгД кДллнйьзав" ї кТЪУ ,,ЫВ, Д.л., 1999 , , - , . ... XX , кДлнйкЙмЦЗ Д.л. тдДгД кДллнйьзав Зй ЗлЦгЦззйв 91 , , , . ... 1 -0,4 3 0 0,4 (B-V)0 0,8 1,2 1,6 -2 5 0 7 V 9 2 Mv 4 11 6 M45 13 8 0 0,4 0,8 B-V 1,2 1,6 . ... кДлнйкЙмЦЗ Д.л. тдДгД кДллнйьзав Зй ЗлЦгЦззйв 93 1950 +24њ +22њ +20њ +18њ +16њ +14њ +12њ Ori Ori Ori +6њ 50 40 30 20 10 0 1950 Tau +10њ +8њ 20 10 0 6 h 5h 50 40 30 20 10 0 4h 50 40 +4њ 3h . ...

... region (region-6.2.2) [xmmsas_20030110_1802-5.4.1] . ... module region _mod subroutine region get parameters; open source list; foreach source transform celestial coordinates to sky location; calculate initial estimated extraction radius; calculate distance to nearest neighbour ; loop sort sources in ascending order of nearest neighbour separation; initialise array of flags; ; First pass considering just nearest- neighbour pairs foreach source in sorted list if( ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...

... THE SIMPLEST MODEL. ... 13, Moscow 119992, Russia E-mail: san@sai.msu.ru Abstract: The analysis of the simplest model shows that an asteroid ­ rubble pile evolves, depending on the parameter V2d (where V is the average velocity of fragments and d is the average distance between fragments), either as a conglomerate of "independent mutually gravitating clusters" (when V2d < fm, where f is the gravitational constant and m is the average mass of a fragment) or as a "receding cluster" (when V2d > fm). ...

. Next: Diameters Up: Derived parameters Previous: Absolute magnitudes Contents . d_stars Compute distance D from parallax, absolute magnitude, or both. Christian Hummel 2015-04-28

... R2517 Date Received: 2009-Jul-02 20:55:18 Technical Page Proposal Type: General Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Urgent Planetary Radar Solar System 17:00 Hours Urgent Proposal for Arecibo Radar Imaging of Near-Earth Asteroid 2009 KC3 We propose radar observations of potentially hazardous asteroid 2009 KC3, which will be a strong imaging target during its approach within 19 lunar distances in August, 2009. ...