Astronotes Armagh Planetarium's Stellar Blog! ... Solar System . ... The theory is known as the Grand Tack as according to it, during the first 10 million years of the Solar systemтАЩs existence Jupiter migrated inwards toward the Sun before turning and coming back, sweeping away all debris that fell into its path. ... Another widely-accepted theory of the formation of the Solar System, the delightfully-named Nice model neatly ties in with the Grand Tack theory as they both support each other. ...

... The discovery of giant Jupiter-type planets in a close proximity to 51 Peg, Boo, and And has prompted the question of where the planets could be formed in the circumstellar disks of solar-type stars. ... Planet formation, at distance of ~0.05 AU from the star, requires that the temperature of the circumstellar protoplanetary disk is low enough for the condensation of rocky materials, and the surface density is sufficiently high. ...

The solar system probably formed about 4.5 billion years ago from a giant disk of gas, dust and ice in space. ... All forms of life on Earth require liquid water to survive, so the presence of liquid water is a good criterion for deciding whether other planets in the universe could be habitable. Earth is the only habitable planet in the solar system. Venus, closer to the Sun, is too hot to have liquid water. Planets and moons in the outer solar system are too cold for liquid water. ...

... New research shows how circumbinary planets form . ... Luke Skywalker s home planet Tatooine would have formed far from its current location in the Star Wars universe, a new University of Bristol study into its real world counterparts, observed by the Kepler space telescope, suggests. ... Circumbinary planets have captured the imagination of many science-fiction writers and film makers; our research shows just how remarkable such planets are, said Stefan Lines from the University of Bristol. ...

3) Planets and Brown Dwarfs . ... By its nature, this method is most sensitive to massive planets orbiting close to their stars. ... That means that some of the more massive extrasolar planets could actually be brown dwarfs (although the statistics of the finds suggest that most of them are not). ... Another possible difference between brown dwarfs and massive planets is how they are born. ... They would base the fundamental definition on the mode of formation: a planet is built from planetesimals. ...

Astronomy Picture of the Day . Uranus: The Tilted Planet . ... This picture was snapped by the Voyager 2 spacecraft in 1986 - the only spacecraft ever to visit Uranus. ... Irregular Galaxy Sextans A . ... But small irregular galaxies form stars too, like this lovely, gumdrop-shaped galaxy, Sextans A. Mars: A Sheer Close Up . ... The Annotated Galactic Center . ... The new large black spot reveals that a volcano named Pillan Patera has been erupting during the interim. ...

... 8, ``Celestial Mechanics'', 2002 Formation and migration of trans -- Neptunian objects S. I. Ipatov 1;2 1 Institute of Applied Mathematics, Moscow, Russia 2 NASA/GSFC, Greenbelt, USA We support the Eneev's idea [1] that the largest (with diameter d?100 km) trans ­ Neptunian objects ( TNOs ) moving now in not very eccentric orbits ... The total amount of water delivered to the Earth during the formation of the giant planets was about the mass of water in the Earth's oceans. ...

. Mars has become the center of intense interest since the Martian Meteorite results were announced. Currently there is a lively debate whether or not primitive life formed there or not.

... Did you know that you're made of stardust? ... Almost everything is made up of materials that were formed in the centre of a star. Anything that wasn't made in a star, is made from the same material as stars gas planets, like Jupiter and Saturn, for example. Once you know that planets are made from the leftover material around forming stars, this makes sense! When a star is born, deep in a cloud of gas and cosmic dust, any leftover material forms a disc around it (like Saturn's rings). ...

... 2001 June 4 . The T Tauri Star Forming System . ... A prototype laboratory for the formation of low mass stars like our Sun is the T Tauri system , one of the brighter star systems toward the constellation of Taurus . In young systems , gravity causes a gas cloud to condense. The situation then usually becomes quite complex, as some of the infalling gas is heated so much by collisions that it is immediately expelled as an outgoing wind . ... About APOD | ...

... B ut Europa's surface is not at all like anything in the inner solar system. ... T he images of Europa's surface strongly resemble images of sea ice on Earth. It is possible that beneath Europa's surface ice there is a layer of liquid water , perhaps as much as 50 km deep, kept liquid by tidally generated heat. ... It is most likely generated by sunlight and charged particles hitting Europa's icy surface producing water vapor which is subsequently split into hydrogen and oxygen. ...

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 ). ...

... Gallery . Astronomy Pictures . ... Sidebar Left . Sidebar Top . No Sidebar . Sidebar Bottom . Sidebar Right . Title: Planet Pictures . Description: All images were taken by Steve Massey . NOTE: All images are copyright and must not be reproduced or mirrored in any form without written permission. Owner: Gallery Administrator . ... Views: 4739 . By: Gallery Administrator . ... Views: 4201 . ... Views: 4091 . ... Powered by Gallery 3.0.9 (Chartres) . ...

... Sciences) - (01.03.02 - Astrophysics and Radioastronomy), Main Astronomical Observatory of Ukrainian National Academy of Sciences, Kyiv, Ukraine. ... Sciences) (01.03.03 - Geliophysics and Solar System Physics), Main Astronomical Observatory of Ukrainian National Academy of Sciences, Kyiv, Ukraine. ... 1977 - 1981 - Engineer, Main Astronomical Observatory, Ukrainian National Academy of Sciences, Kiev, Ukraine . ... Institute: Main Astronomical Observatory of Ukrainian National Academy of Sciences . ...

Class 1 Introduction, Background History of Modern Astronomy The Night Sky, Eclipses and the Seasons Kepler's Laws Newtonian Gravity General Relativity Matter and Light Telescopes Class 2 Solar System Characteristics Formation Exosolar Planets Class 3 Stars The Sun Stellar Evolution of Low and High Mass Stars Deaths of Stars Exotic Stars Class 4 Galaxies Galaxy Classification Formation of Galaxies Galactic Evolution ... So far, one planet has been studied by this method. ...

On the inclination of planetary orbits! Caroline Terquem! ... Planets on inclined orbits Higher inclinations for planets around stars with Teff>6250K? Planet formation, Hot Jupiters and misalignments 1. If planets form by the core accretion scenario and migrate in: Hot Jupiters But no eccentricity and no misalignment (if the disc is in the star's equatorial plane) With further planet/planet scattering and/or Kozai cycles: Eccentricity and misalignment But companions required.. ...

... Bad Astronomy . ... Bitesize Astronomy . ... The Nine Planets . ... Hey, it's either this or one of those really irritating PayPal donation buttons here. ... I have a snack from April 1998 that gives a brief intro to these peculiar objects , but briefly, brown dwarfs (or BDs for short) are objects that are a little less massive than "normal" stars, but bigger than any planets we currently know about. ... A star forms from a collapsing gas cloud. ... One more point: is a BD a star? ... 2008 Phil...

... part 2 | ... Part 1 . The new concept of formation and development of the Solar system. ... Thus, the initial pulse of the rotation of a protosolar cloud of the solar system was determined as a result of the diversion of a part of the moment of the rotational pulse of the Galaxy. ... Besides this new approach to the pre-solar system as a system of the destroyed vortex structure, we can understand now a number of other peculiarities of the Solar system's structure. ...

Jupiter is the largest of the nine planets, more than 10 times the diameter of Earth and more than 300 times its mass. ... The mean density of Earth is 5.245 times that of water. The pull of gravity on Jupiter at the top of the clouds at the equator is 2.4 times as great as gravity's pull at the surface of Earth at the equator. ... It is tipped about 11њ to Jupiter's axis of rotation, similar to Earth's, but it is also offset from the center of Jupiter by about 10,000 kilometers (6,200 miles). ...

... A dynamo is created in a magnetic field by an electric circuit, part of which is moving relative to the rest (additional conditions must also be met). ... Furthermore, the plasma between them conducts electricity very well along its magnetic field lines, which act as if they were wires connecting Io and the planet (drawing). ... The drawing is not to scale. ... The Hubble Space Telescope , using its Wide Field and Planetary Camera 2, has been photographing auroras of the planet Jupiter. ...