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. ...

... More on 51 Peg: . The discovery of a Jupiter--mass planet in orbit around the solar--type star 51Peg has been reported by Michel Mayor and Didier Queloz (Geneva Observatory) on October 6th at the 9th Cambridge workshop on "cool stars, stellar systems, and the sun" held at Florence (Italy). ... Recall that the measurements of radial velocity only yield v sin i which in turn gives us M sin i. For most values of i, sin i will be greater than 0.5 and this gives a mass estimate of 0.5 Jupiter masses. ...

... Credit: Greg Bacon ( STScI ), NASA Explanation: The last decade saw the profound discovery of many worlds beyond our solar system, but none analogs of our home planet Earth . Exploiting precise observational techniques, astronomers inferred the presence of well over two dozen extrasolar planets , most nearly as massive as gas giant Jupiter or more, in close orbits around sun-like stars. ... Publications with keywords: extrasolar planet - planet - Saturn - planetary system . ... Crescent Saturn . ...

... Tonight's Sky . ... The Magazine . ... Star Atlas . ... An artificial comet holds secrets to Earths life . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... The planet has extreme temperature swings and perhaps active lava flows. ... A digital supplement to Astronomy magazine. ... Join TravelQuest International with Astronomy and Discover magazines on one of three great tour options surrounding this celestial spectacle . ... Astronomy Magazine . ...

... Jupiter is our Solar System?s very own superhero. The giant planet is two and a half times more massive than all the rest of the planets in our Solar System combined. And with great mass, comes great gravity. With the power of super-strong gravity, Jupiter plays a heroic role in our Solar System, protecting life on Earth. ... Unfortunately, we have found lots of solar systems with massive planets that lie close to their star, but not so many that lie far away, like Jupiter. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Solar System . ... Planets . ... This bizarrely shrunken planetary system was found by NASAтАЩs Kepler mission, hence the parent star has been named Kepler-11. ... Planetary scientist and Kepler science team member Jack Lissauer said ?These six planets are mixtures of rock and gases, possibly including water.тАЭ €аNone of these strange new worlds are likely to be home to any form of life; their surface conditions are simply too extreme. ...

My research efforts have focused on three areas which are: . More than 200 extrasolar planets have been discovered around relatively nearby stars, primarily through the Doppler line shifts owing to the reflex motions of their host stars, and more recently through transits of some planets across the face of the host stars. ... Gravitational microlensing provides a novel technique to look for planets around lens stars, and this is the only technique currently capable of detecting Earth-mass planets. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... I had to lean backwards a little to make sure we didn't topple over, and as I spun her in a big circle around me I made a little circle on the floor too. ... The Earth, for example, has a mass about 81 times that of the Moon. ... It is mathematically correct to say that it is the barycenter that orbits the Sun, while the Earth and Moon circle the barycenter. ... 2008 Phil Plait. ...

... Image courtesy of Korea Astronomy and Space Science Institute . ... There are already 29 multi-planet extrasolar planetary systems discovered (including this last one), so what makes this particular system unique? ... International Year of Astronomy, Ireland National Node . ...

The stability of planetary systems after stellar mass loss : Prospects for White Dwarf planets and pollution Alexander James Mustill1*, Dimitri Veras2, Eva Villaver3, Amy Bonsor4, Boris GДnsicke2, Mark Wyatt 1 2 5 Lund Observatory ... 1TL, United Kingdom 5 Institute of Astronomy, University of Cambridge, Madingley Road, CB3 9ET, UK *alex@astro.lu.se Stars lose mass as they evolve to become white dwarfs ( WDs ), and this mass loss can induce ...

Determination of mass of Jupiter and that of some minor planets from observations of minor planets moving in 2:1 commensurability with Jupiter Olga M. Ko chetova and Yulija A. Chernetenko Institute of Applied Astronomy, St. Petersburg, Russia September 19, 2000 Keywords: Jupiter 's mass , asteroid's masses , observations of minor planets Great numb er of observations of minor ... Hoffmann (1989) p ointed out the fruitfull of that approach. ... Table II. ...

... 2002 May 9 . Planets Over Stonehenge . ... Explanation: Stonehenge , four thousand year old monument to the Sun , provides an appropriate setting for this delightful snapshot of the Sun's children gathering in planet Earth's sky. While the massive stone structure dates from around 2000 B.C. , this arrangement of the visible planets was recorded only a few days ago on the evening of May 4th, 2002 A.D. Bright Jupiter stands highest above the horizon at the upper left. ... About APOD | ...

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). ...

Giant Jupiter. Jupiter . ... Jupiter has no solid surface that is why speaking about its dimensious point the radius of the upper border line of the clouds, where the presseru is about 10 KPa; radius of Jupiter on the equator is 71400 km. ... The Jupiter satellites. ... Nowadays 16 satellites of the Jupiter are known: Adrastea, Mitis, Amaltea , Phina,then 4 Galilei satellites: Io , Europe , Hanimed , Callisto , Leda, Aimalia, Zicitea, Elara, Ananke, Carme, Pasipe and Sinope. ... Jupiter's ring. ...

... Neptune is smaller in diameter but larger in mass than Uranus . ... N eptune has been visited by only one spacecraft, Voyager 2 on Aug 25 1989. ... A t the time of the Voyager encounter, Neptune's most prominent feature was the Great Dark Spot (left) in the southern hemisphere. ... Neptune's winds blew the Great Dark Spot westward at 300 meters/second (700 mph). ... L ike Uranus and Jupiter, Neptune's rings are very dark but their composition is unknown. ... Neptune's Ring System . ... Uranus .. ...

... The study of extra solar planets will be one of the most important areas of research in astronomy in this century. ... The first planets outside the solar system were found in 1992 around the millisecond pulsar PSR B1257+12 by Alex Wolszczan at the Arecibo Observatory . ... Three space missions based on this principle (MOST, COROT and Kepler ) have already been launched or approved, and have the last one at least has the potential to find Earth-sized planets. ... SIM ( NASA ) is one of such missions...

... Moon Phase below . ... ARTICLE: Why the moon always shows us the same face . ... Before you continue reading, you should know that this was not always the case, i.e. the Moon once was rotating with respect to the Earth, so that on every night a terrestrial observer (if there was one, because this was long, long before mankind appeared on our planet, and even before any major animals had appeared) saw another face of the Moon. ... Figure 1 (not to scale) shows how we can imagine the system Earth-Moon...

5th of July 2015 . Planet formation around HD100546 . ... Australia Telescope Compact Array (ATCA) image of the protoplanetary disk around the young star HD100546. This young, massive star is about 100 pc from the Earth and the image shows the thermal emission from the dusty disk seen at a wavelength close to 7 mm. The emission is shaped like a horseshoe, with material from the inner disk being cleared out by an embedded planet. Image adapted from Wright et al. ... today * ATNF | ...

In ancient times the solar system was thought to be the whole Universe, so the study of planetary motions was cosmology. ... The planets other than the Moon and Sun generally move West to East through the stars, but occasionally stop and move in the opposite direction ( retrograde motion). In order to explain the retrograde motion of the planets, the geocentric model of the Solar System shown above puts the planets on small circles called epicycles . ...

... GSAOI Home . ... Science . ... Deep imaging at J , H , and K is required to identify all stellar objects, brown dwarfs, and planetary mass objects in the central region of the Orion Nebula Cluster down to masses comparable to that of Jupiter. This is required to establish the initial mass function, i.e., the number of stars of each mass that have formed, in this region of intense massive star formation. ... The fields of the GSAOI detectors are shown as four green squares in each frame. ...