... How much brighter is the Sun as viewed from the planet Mercury as compared to Earth ? ... Actually, all of these questions can be answered through a very simple mathematical relationship known as the inverse square law. ... As the distance from the Sun increases the surface area of the sphere grows by the square of the distance. ... Common sense tells us that the Sun will be brighter and the inverse square law tells us how much brighter. ... gr = 0.912 G or 91.2% gravity felt at Earth's surface. ...

... Gravitational wave search provides insights into galaxy evolution and mergers . ... galaxies . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... What are typical star-to-star distances in globular clusters compared to stellar distances in our region of the galaxy? ... RELATED TOPICS: GLOBULAR CLUSTERS . ... Get instant access to subscriber content on Astronomy.com! ...

... Jupiters Rings Revealed . ... Data from the Galileo spacecraft currently orbiting Jupiter later confirmed that these rings were created by meteoroid impacts on small nearby moons. ... With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star's life occurs as its outer layers are ejected - its core becoming a cooling, fading white dwarf. ... Previously, the waning Moon was best visible from all places on Earth during the early morning hours because it trailed the Sun....

Star formation is often best manifested by bright H II regions.These are regions of hydrogen which have been ionized by ultraviolet photons which are emitted from massive stars (typically stars more than 20 times the mass of the Sun). ... A narrowband filter image centered on this wavelength will then readily reveal these H II regions and hence the current sites of star formation in a galaxy, The luminous blobs that can be seen here are all H II regions . ... NGC 3558 Visual . NGC 3558 Infrared . ...

As the Universe expands, gravity pulls on the Universe, and slows the expansion down over time. As we look to great distances, we are looking back in time. If we can measure how fast the Universe is expanding in the past, and compare it to how fast it is expanding now, we can see the total gravitational effect of all matter in the Universe. Here we plot the distance between two galaxies as a function of time. ... Universes with lots of material . ...

... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Australia Telescope 20GHz Survey . ... Bright prospects: Comparing the H Survey with large-scale radio continuum emission . ... Prospects for comparisons between the AAO/UKST H \ survey and large-scale radio continuum emission are considered, with particular reference to the recently completed Parkes 2.4-GHz survey of the southern Galactic Plane. ...

... 2012 November 27 . Bright Jupiter in Taurus . ... Explanation: That bright star you've recently noticed rising just after sunset isn't a star at all. ... Clearly outshining yellowish Aldebaran, alpha star of Taurus, Jupiter is centered in this skyview from November 14th, also featuring the Pleiades and Hyades star clusters, familiar celestial sights as the northern hemisphere winter approaches. ... Of course, you can imagine NASA's Dawn spacecraft in this field of view. ... About APOD | ...

Astronotes Armagh Planetarium's Stellar Blog! ... Planets . ... Monthly Sky Notes . ... October . ... By admin October 8, 2010 Posted in: Monthly Sky Notes . A giant from close up: an image made using data from the Cassini probe which flew past Jupiter in 2000. ... As it is so far from us, it takes JupiterтАЩs light a significant time to reach us тАУso when you see Jupiter tonight you are seeing it as it was 35€а minutes in the past. ... Posted October 12, 2010 at 11:15 PM . ... Astronotes . ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

... Mass . 17a. Measuring Mass . ... A medium-size (1.25 inch wide) binder clip, as is used in offices to hold papers together--the type made of flat blue steel, with two wire handles. ... The theory predicts that the oscillation period should be proportional to the square root of the oscillating mass, including the mass of the clip. Note that gravity plays no part here: the oscillation period would be the same on the Moon or in zero-g. Denoting square root by SQRT, we have . ...

... In summer 1994, the biggest news in astronomy was the collision of comet Shoemaker-Levy 9 with Jupiter. During this school year, Jupiter will charge back into the limelight with the arrival of the Galileo spacecraft (see figure 8 ). On Dec. 7, following a tortuous six-year ramble through the solar system, Galileo will begin its two-year mission studying Jupiter and its gaggle of moons. ... Besides the camera, Galileo will carry instruments capable of identifying minerals on Jupiter's moons. ...

Saturn: The beauty of the rings. Saturn . ... Belongs to the giant planets . It has no definite solid surface. ... The free fall acceleration at the Saturn surface near equator is 9,06 m/s^2 . ... In the centre of the planet the temperature is about 20000K. The satellites . ... The rings of Saturn . ... It is proved that Saturn's rings (as well as the other planet's) are the fragments of the great cloud being near the planet with million kilometres length (see how the rings were formed ). ...

Ganymede . ... Ganymede Statistics . ... Hubble Finds Ozone on Jupiter's Moon Ganymede . ... Like Callisto , Ganymede is most likely composed of a rocky core with a water/ice mantle and a crust of rock and ice. ... Ganymede's mantle is most likely composed of ice and silicates, and its crust is probably a thick layer of water ice. ... Ganymede's surface is rich in water ice and Voyager and Galileo images show features which are evidence of geological and tectonic disruption of the surface in the past. ...

Whoever looked up at the sky at dusk on Monday, 1st December was fortunate enough to see one of the most beautiful night-sky views of the year тАУ a massing of planetary bodies in the south-west. The gas giant planet, Jupiter, was nearly in conjunction with bright, тАШevening starтАЩ, Venus, and the Moon. ... The images show, respectively, the telescope and Venus emerging from behind the Moon, after the end of the occultation, while Jupiter is above and to the right. ...

LIPSKIY-RODIONOVA' LUNAR ANTIPODES AS PRECURSORS OF A REGULAR WAVE PLANETOLOGY G.G.Kochemasov IGEM of the Russian Academy of Sciences, Moscow, Russia kochem@igem.ru / Fax: (009)(095)230 21 79 The first observations of the lunar far side allowed to compare it with the near side and draw very important conclusions in the very beginning of planetary studies based on spacecrafts. ... Celestial bodies are dichotomic. ... The concept of celestial bodies includes Sun (a star) as one of them. ...

GHRS Instrument Handbook 4.1 111 Index 112 GHRS Instrument Handbook 4.1 A Accumulation Mode 15, 20, 34, 43--45 CENSOR 45 details 88--89 COMB 16, 44 DOPPLER 45, 104--105 FP­SPLIT 16, 44 parameter summary 44 STEP­PATT 17, 44, 84 STEP­ TIME 45 substepping 20 acquisitions 17, 18, 25, 34, 34--41 ACQ/ PEAKUP , see acquisitions , ...

Constraining the Cosmic Mass Density from the SBF Survey Peculiar Velocities J.P. Blakeslee et al. University of Durham, U.K. The recently completed I-band Surface Brightness Fluctuations (SBF) Survey of Galaxy Distances includes high-quality distance measurements to nearly 300 early-type galaxies within 4000 km/s. We compare the peculiar velocities observed in this survey with those predicted from the galaxy density eld found in ux-limited redshift surveys. ...

... Bad Astronomy . Misconceptions . ... Mad Science . ... The Nine Planets . ... Hey, it's either this or one of those really irritating PayPal donation buttons here. ... Brown Dwarfs . ... Mr. Hazlewood and many others on the web claim that Planet X is a brown dwarf. ... Ms. Lieder claims that Planet X has a mass something like 5 times the Earth's mass, which is more like a normal planet than a brown dwarf. ... Conclusion: Doomsayers claim Planet X is a brown dwarf (or even a massive planet). ...

Finding Himalia, The Fifth Brightest Moon Of Jupiter . Articles | ... Himalia is the only moon other than the Galilean moons of Jupiter that is visible in an amateur size telescope. ... I normally use “The Sky” from Software Bisque for planning my observing sessions and in helping me find objects, but it only has the Galilean moons for Jupiter so I used Red Shift (version 3 at the time) which I also had on my computer. ... www.astronomy.net . ... dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

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