Thursday, December 20, 2012

Asteroids and comets visited by spacecraft as of December 2012


Toutatis asteroid went by and China's Chang'E 2 photographed it but I didn't hear much fanfare.
There have been other asteroids and comets visited by spacecraft and hopefully the information obtained will be useful should we want to know how to change their orbits to avoid a collision with Earth or modify an orbit to capture one for space mining.  I hope we have some idea of their radiation history and what risks would be involved with sending humans  to one as I hear mumbles about doing so.
 - LRK -

Emily Lakdawalla of the Planetary Society has put together aN asteroids-and-coments montage.
- LRK -

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My ever-popular asteroids-and-comets montage, now in color, with bonus Toutatis
Posted By Emily Lakdawalla
2012/12/18 04:26 CST
My collage of all the asteroids and comets visited by spacecraft is probably the single most popular image I have ever posted on this blog. I've now updated it to be in color and to include Toutatis, which Chang'E 2 photographed last week. When I first started working on a color version, it didn't seem to hang together very well as a composition, because the colors were all over the map. But when I hit upon the idea of trying to represent the bodies with correct relative brightness, it seemed to come together nicely. Vesta is not included because it dwarfs the others. (I'd have to increase the height and width of the montage by factors of three.)
Asteroids and comets visited by spacecraft as of December 2012, in color, excepting Vesta
Montage by Emily Lakdawalla. Data from NASA / JPL / JHUAPL / UMD / JAXA / ESA / OSIRIS team / Russian Academy of Sciences / China National Space Agency. Processed by Emily Lakdawalla, Daniel Machacek, Ted Stryk, Gordan Ugarkovic.
https://planetary.s3.amazonaws.com/assets/images/9-small-bodies/2012/20121218_asteroids_comets_sc_0-000-100_2012_color_brightened_f840.png
Asteroids and comets visited by spacecraft as of December 2012, in color, excepting Vesta
A montage of 16 of the 17 asteroids and comets that have been photographed up close as of December 2012, when Chang'E 2 flew past Toutatis. This version is in color and shows the bodies at their correct relative (though not absolute) albedo or brightness. Not included is Vesta, which would cover an area about three times the width and height of this montage.

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Some information on spacecraft that have visited asteroids and coments.
- LRK -

List of asteroids visited by spacecraft

Category:Comets visited by spacecraft

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NASA images Touatis with ground radar.
- LRK -

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Asteroid Toutatis Slowly Tumbles by Earth
by Staff Writers
Pasadena CA (JPL) Dec 17, 2012

Scientists working with NASA's 230-foot-wide (70-meter) Deep Space Network antenna at Goldstone, Calif., have generated a series of radar data images of a three-mile-long (4.8-kilometer) asteroid that made its closest approach to Earth on Dec. 12, 2012.

The images that make up the movie clip were generated with data taken on Dec. 12 and 13, 2012. On Dec. 12, the day of its closest approach to Earth, Toutatis was about 18 lunar distances, 4.3 million miles (6.9 million kilometers) from Earth. On Dec. 13, the asteroid was about 4.4 million miles (7 million kilometers), or about 18.2 lunar distances.

The radar data images of asteroid Toutatis indicate that it is an elongated, irregularly shaped object with ridges and perhaps craters. Along with shape detail, scientists are also seeing some interesting bright glints that could be surface boulders.

Toutatis has a very slow, tumbling rotational state. The asteroid rotates about its long axis every 5.4 days and precesses (changes the orientation of its rotational axis) like a wobbling, badly thrown football, every 7.4 days.The orbit of Toutatis is well understood. The next time Toutatis will approach at least this close to Earth is in November of 2069, when the asteroid will safely fly by at about 7.7 lunar distances, or 1.8 million miles (3 million kilometers).
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China's flyby of Toutatis with Chang'e-2 spacecraft.
- LRK -

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China Makes First Asteroid Fly By
by Staff Writers
Beijing (XNA) Dec 17, 2012
China's space probe Chang'e-2 has successfully conducted a maneuver in which it flew by the asteroid Toutatis, about seven million km away from the Earth.

Travelling in deep space, Chang'e-2 made the flyby on Dec. 13 at 16:30:09 Beijing Time (08:30"09 GMT), the State Administration of Science, Technology and Industry for National Defense (SASTIND) announced on Saturday.

The flyby was the first time an unmanned spacecraft launched from Earth has taken such a close viewing of the asteroid, named after a Celtic god.

It also made China the fourth country after the United States, the European Union and Japan to be able to examine an asteroid by spacecraft.

Chang'e-2 came as close as 3.2 km from Toutatis and took pictures of the asteroid at a relative velocity of 10.73 km per second, the SASTIND said in a statement.

Sources with the administration told Xinhua that Chang'e-2 is continuing its deep space travel and will reach a distance of more than 10 million km away from Earth in January next year.

Chang'e-2 was launched on Oct. 1, 2010 from Xichang Satellite Launch Center and later orbited the moon to finish a more extensive probe than its predecessor Chang'e-1.

Chang'e-2 left its lunar orbit for an extended mission to the Earth-Sun L2 Lagrangian point on June 9, 2011, after finishing its lunar objectives, which collected data for a complete lunar map.

The probe departed from L2 this year and began its mission to Toutatis.snip
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Post Cina . org
- LRK -

You are here: Home > China > Nation
Chinese space probe flies by asteroid Toutatis
Xinhua, December 15, 2012

China's space probe Chang'e-2 has successfully conducted a maneuver in which it flew by the asteroid Toutatis, about seven million km away from the Earth.

China's space probe Chang'e-2 has successfully conducted a maneuver in which it flew by the asteroid Toutatis, about seven million km away from the Earth. [Photo: Chinanews.com]

Travelling in deep space, Chang'e-2 made the flyby on Dec. 13 at 16:30:09 Beijing Time (08:30"09 GMT), the State Administration of Science, Technology and Industry for National Defense (SASTIND) announced on Saturday.
The flyby was the first time an unmanned spacecraft launched from Earth has taken such a close viewing of the asteroid, named after a Celtic god.
It also made China the fourth country after the United States, the European Union and Japan to be able to examine an asteroid by spacecraft.
Chang'e-2 came as close as 3.2 km from Toutatis and took pictures of the asteroid at a relative velocity of 10.73 km per second, the SASTIND said in a statement.
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You can reach these celestial bodies with conventional rockets.  Just be prepared to spend a few years en route.

Thanks for looking with me.
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WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK -
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