... 2015 January 29 . Close Encounter with M44 . ... Explanation: On Monday, January 26, well-tracked asteroid 2004 BL86 made its closest approach, a mere 1.2 million kilometers from our fair planet. ... The remarkably pretty telescopic field of view includes M44, also known as the Beehive or Praesepe star cluster in Cancer. Of course, its close encounter with M44 is only an apparent one, with the cluster nearly along the same line-of-sight to the near-earth asteroid. ... About APOD | ...

... Credit Copyright: Carlo Dellarole, Andrea Demarchi Explanation: On Monday, January 26, well-tracked asteroid 2004 BL86 made its closest approach, a mere 1.2 million kilometers from our fair planet. ... The remarkably pretty field of view includes M44, also known as the Beehive or Praesepe star cluster in Cancer. Of course, its close encounter with M44 is only an apparent one, with the cluster nearly along the same line-of-sight to the near-earth asteroid. ... Publications with keywords: asteroid . ...

With this knowledge of orbits, we are ready to plan a trip to Mars. ... The spacecraft will already have the 107,000 kilometers per hour (66,500 miles per hour) speed of Earth, whereas Mars moves at only 86,900 kilometers per hour (53,900 miles per hour). ... A speed of about 42,000 kilometers per hour will be enough to escape the Earth's gravity and, when added to the Earth's orbital speed around the Sun, put the spacecraft on a Hohmann transfer orbit to the Red Planet. ... 1,570,000 . ... Earth . ...

The Moon orbits around the Earth. ... To keep the Moon moving in that circle--rather than wandering off--the Earth must exert a pull on the Moon, and Newton named that pulling force gravity . ... If it was the same force, then a connection would exist between the way objects fell and the motion of the Moon around Earth, that is, its distance and orbital period. ... Newton went further and proposed that gravity was a "universal" force, and that the Sun's gravity was what held planets in their orbits. ...

... Bad Astronomy . ... Bitesize Astronomy . ... The Nine Planets . ... The Sun stays at the center and the planets orbit it serenely, each in its place. ... Tiny Pluto, orbiting the Sun an average of nearly 40 times the Earth's orbital radius, has an odd orbit. Most planets orbit the Sun in nearly perfect circles, but Pluto's orbit is noticeably elliptical. ... The orbits of Pluto and Neptune have a coincidental timing to them: Pluto orbits the Sun twice for every three times Neptune does. ...

Comets necessarily obey the same physical laws as every other object. ... If one considers only two bodies -- either the Sun and a planet, or the Sun and a comet -- the smaller body appears to follow an elliptical path or orbit about the Sun, which is at one focus of the ellipse. ... Another quantity that is conserved is called angular momentum. ... Comets simply are bodies which in general have more angular momentum per unit mass than do planets and therefore move in more elongated orbits. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Armagh Observatory, 11 June 2015: Armagh Observatory reports that the next two weeks will provide an interesting opportunity to observe the brightest planet, Venus, and the largest planet, Jupiter, as they move towards one another in the evening twilight. ... The image shows the sky view towards the West at around 11pm on 20 June 2015. ... Professor Mark E. Bailey, Armagh Observatory, College Hill, Armagh BT61 9DG. ...

... Planets . ... Earth Satellites . ... Looking in the direction of the constellation Cygnus the Swan and launched by NASA in 2009 is the Kepler Space Observatory.Many previous missions searching for exoplanets mainly detected large giant planets, like large hot Jupiters (it is easier to detect larger planets).However KeplerтАЩs main objective is to search for much smaller planets located in a habitable zone which is not too close nor too far from their star; planets which may be just like our Earth. ...

... 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. ...

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 . ...

. If an object is moving so fast that its kinetic energy exceeds this, it can escape out into space, never to return. Thus . Previous slide . Next slide . Back to first slide . View graphic version .

... In a game of ping-pong, suppose a paddle moves at 20 miles per hour and hits a ball with 20 mph in the opposite direction. ... In the new problem, a ball moving at -40 mph hits a non-moving surface; if the collision is elastic (no energy lost), that ball returns with the same speed but in the opposite direction, i.e. its velocity reverses sign. ... Something very similar happens when a spacecraft with velocity v passes close to a moving planet and is deflected. ... Could Earth capture a second moon?...

... Central to this vision has been the idea that the way to discover new worlds around distant stars is by someday traveling there in person. ... I am a graduate student in astrophysics at UC Berkeley, home of one of the most successful planet searches presently underway. ... We can see the planets in our own solar system by reflected sunlight, but only at night when the sun?s glare does not obscure them. ... Planets are thought to form from a disk of gas and dust swirling around an infant star. ...

... Science User Portal . ... For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves from one side of its host star to the other. ... Only 12 million years old, or less than three-thousandths of the age of the Sun, Beta Pictoris is 75% more massive than our parent star. ... This research was presented in a paper to appear this week in Science Express (тАЬA Giant Planet Imaged in the disk of the Young Star Beta Pictoris,тАЭ by A.-M. Lagrange et al.) ...

... 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. ...

This service is intended as an aid to visually observing close-approaching asteroids. ... By clicking on the column headers for "Object Name", "Maximum Brightness", and "Maximum Angular Speed", you can sort the list by those fields. ... When This is the predicted time when the asteroid will be closest to the Earth. ... This field shows red if an asteroid comes as close as the moon. ... PHA (Potentially Hazardous Asteroid) This does NOT mean that this is going to hit the Earth. ...

... The function is accessible, if the file with the image is open, and Ю identification of a star field is made. ... a) Load a first image by the command " Open ", and others by the command " Open +". b) Make an identification of the field. c) Open the menu " File ", select " Next " or press . ... It is necessary tree or more images. a) Load the first image by the command " Open" , and others by the command " Open + ". b) Open the menu " Marking ", select "Detect moving objects" or press - . ...

... It is also our solar system's tenth planet. ... The astronomers first imaged 2003 UB313 October 21, 2003 -- but the ice world moved so slowly along its orbit it eluded software designed to look for moving targets until the scientists reanalyzed their images January 5, 2005. ... But Brown's crowning of 2003 UB313 as a tenth planet has rankled some astronomers and reinvigorated the simmering debate over how to define a planet -- and if any scientifically useful definition can include Pluto. ...

... SATELLITE: An object that revolves around a planet. ... SIDEREAL DAY: The length of a planet's rotation period relative to the stars. SOLAR SYSTEM: The sun and all the objects that are held in its gravitational field and move around it. ... SUPERIOR CONJUNCTION: The position of a planet when it is on the opposite side of the Sun from Earth (thus making in invisible). ... TRANSIT: The movement of an object between the Earth and the Sun and showing on the surface of the sun as a black dot. ...

The average height of the platform is kept constant using the distomats (laser rangers) and the tiedowns. ... Data was taken on 29jul02 with the azimuth at 242.87 degrees and the dome at 10 degrees za. The tiedowns made two motions of .2 inches and .16 inches while the tilt sensors where running. The plot shows the pitch and roll of the tilt sensors during the tiedown motion (.ps) ( .pdf ). ... The motions we see in the tilt sensors would map into small pointing errors. ...