2010 TK7 - Earth's First Found Trojan Asteroid

orb

O-F Administrator,
News Reporter
Joined
Oct 30, 2009
Messages
14,020
Reaction score
4
Points
0
NASA / NASA JPL:
NASA's WISE Finds Earth's First Trojan Asteroid

July 27, 2011

PASADENA, Calif. – Astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known "Trojan" asteroid orbiting the sun along with Earth.

Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.

Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view.

"These asteroids dwell mostly in the daylight, making them very hard to see," said Martin Connors of Athabasca University in Canada, lead author of a new paper on the discovery in the July 28 issue of the journal Nature. "But we finally found one, because the object has an unusual orbit that takes it farther away from the sun than what is typical for Trojans. WISE was a game-changer, giving us a point of view difficult to have at Earth's surface."

The WISE telescope scanned the entire sky in infrared light from January 2010 to February 2011. Connors and his team began their search for an Earth Trojan using data from NEOWISE, an addition to the WISE mission that focused in part on near-Earth objects, or NEOs, such as asteroids and comets. NEOs are bodies that pass within 28 million miles (45 million kilometers) of Earth's path around the sun. The NEOWISE project observed more than 155,000 asteroids in the main belt between Mars and Jupiter, and more than 500 NEOs, discovering 132 that were previously unknown.

The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.

{colsp=2}
Click on images for details​
|
This artist's concept illustrates the first known Earth Trojan asteroid, discovered by WISE. The asteroid is gray and its extreme orbit is shown in green.
Image credit: Paul Wiegert, University of Western Ontario, Canada​
|
Asteroid 2010 TK7 is circled in green, in this single frame taken by NASA's Wide-field Infrared Survey Explorer, or WISE.
Image credit: NASA/JPL-Caltech/UCLA​
|

The asteroid is roughly 1,000 feet (300 meters) in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 50 million miles (80 million kilometers) from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 15 million miles (24 million kilometers). An animation showing the orbit is available at: http://www.nasa.gov/multimedia/videogallery/index.html?media_id=103550791.

"It's as though Earth is playing follow the leader," said Amy Mainzer, the principal investigator of NEOWISE at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Earth always is chasing this asteroid around."

A handful of other asteroids also have orbits similar to Earth. Such objects could make excellent candidates for future robotic or human exploration. Asteroid 2010 TK7 is not a good target because it travels too far above and below the plane of Earth's orbit, which would require large amounts of fuel to reach it.

"This observation illustrates why NASA's NEO Observation program funded the mission enhancement to process data collected by WISE," said Lindley Johnson, NEOWISE program executive at NASA Headquarters in Washington. "We believed there was great potential to find objects in near-Earth space that had not been seen before."

{...}



NASA Press Release: RELEASE : 11-247 - NASA's Wise Mission Finds First Trojan Asteroid Sharing Earth's Orbit
 

orb

O-F Administrator,
News Reporter
Joined
Oct 30, 2009
Messages
14,020
Reaction score
4
Points
0
I don't know if I even want to bother asking how it orbits like that. :blink:
It doesn't orbit like that. It's just a path it draws relative to the orbit of Earth.
 

Notebook

Addon Developer
Addon Developer
News Reporter
Donator
Joined
Nov 20, 2007
Messages
11,813
Reaction score
640
Points
188
Its sort of rolling around the gravity hole the Earth pushes in front of it, if you see what I mean. Not sure I do.

N.
 

clickypens

Orbinauta
Joined
Mar 21, 2009
Messages
205
Reaction score
0
Points
0
It'd be interesting to put this in Orbiter and try to fly to it. Looks fun and challenging
 

C3PO

Addon Developer
Addon Developer
Donator
Joined
Feb 11, 2008
Messages
2,604
Reaction score
17
Points
53
Lagrange orbits always looked "impossible" to me :lol:
 

fsci123

Future Dubstar and Rocketkid
Addon Developer
Joined
Aug 18, 2010
Messages
1,536
Reaction score
0
Points
0
Location
?
WOW.

I remember when there wasn't a Trojan in our system.
 

perseus

Addon Developer
Addon Developer
Joined
May 31, 2008
Messages
316
Reaction score
1
Points
18
A handful of other asteroids also have orbits similar to Earth. Such objects could make excellent candidates for future robotic or human exploration. Asteroid 2010 TK7 is not a good target because it travels too far above and below the plane of Earth's orbit, which would require large amounts of fuel to reach it.

It could take a flight to the Moon and make a Sling-shoot to change the orbital plane and get up Asteroid 2010 TK7.
 

squeaky024

New member
Joined
May 26, 2010
Messages
128
Reaction score
0
Points
0
Location
Here.
Website
www.google.com
Don't worry guys, the Earth has a good anti-virus, that trojan can't harm us. :lol:

I wonder if there is one behind us in our orbit.
 

GigaG

New member
Joined
Jul 6, 2011
Messages
72
Reaction score
0
Points
0
So, I'm not clear how it moves. Does it, like, loop in ovals around Earth's orbit?
 

tblaxland

O-F Administrator
Administrator
Addon Developer
Webmaster
Joined
Jan 1, 2008
Messages
7,320
Reaction score
25
Points
113
Location
Sydney, Australia
So, I'm not clear how it moves. Does it, like, loop in ovals around Earth's orbit?
No, it orbits the Sun in an orbit quite similar to Earth's. In the animations, what you are seeing is the motion of the asteroid in a rotating frame of reference such that the Sun and Earth are static in it - essentially you are seeing the asteroid's motion relative to Earth.

The asteroid is close to the L4 Lagrange point where it is effected by the gravity of both the Sun and the Earth, so its orbital parameters are always changing slightly (eg, sometimes it has a higher orbital period than Earth, sometimes lower, so it moves closer and further away from Earth over time). In the Sun-Earth rotating reference frame the asteroid "orbits" this L4 point. I use the term "orbit" loosely since the motion is not really periodic, but rather a non-closed Lissajous curve in that rotating reference frame.
 

N_Molson

Addon Developer
Addon Developer
Donator
Joined
Mar 5, 2010
Messages
9,271
Reaction score
3,244
Points
203
Location
Toulouse
It would probably be a good target for a NEO manned "landing" mission. The good point being that its distance to the Earth stays roughly the same, if I understood it well.

(I don't think the orbital plane would be a problem ?)
 
Top