(308635) 2005 YU ₅₅

Asteroid (308635) 2005 YU 55
Properties of the orbit ( animation ) Epoch:  September 30, 2012 ( JD 2,456,200.5)
Orbit type	Apollo type
Major semi-axis	1.1573  AU
eccentricity	0.4305
Perihelion - aphelion	0.6591 AU - 1.6555 AU
Inclination of the orbit plane	0.3406 °
Sidereal period	1.25 a
Physical Properties
Medium diameter	approx. 400 meters
Rotation period	18 h
Absolute brightness	21.1 mag
Spectral class	C.
history
Explorer	Robert S. McMillan
Date of discovery	December 28, 2005
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

(308635) 2005 YU ₅₅ is a near-Earth and potentially dangerous asteroid of the Apollo type that was discovered on December 28, 2005 as part of the Spacewatch project by Robert S. McMillan at the Steward Observatory of the Kitt Peak National Observatory on Kitt Peak was discovered in Arizona . It has a diameter of about 400 m. On November 8, 2011 at 23:28 UT , the asteroid passed Earth at about 0.85 times the lunar distance. Since the 2010 XC ₁₅ approach in 1976, no asteroid with comparable brightness has come this close to Earth.

Assessment of the risk of a collision

Animation of the flyby on November 8th and 9th 2011 from (308635) 2005 YU ₅₅ compared to the orbits of the earth and moon.

In February 2010, the asteroid was rated 1 on the Turin scale , which indicates a near-earth flyby that does not represent an exceptional hazard. On April 19, 2010, observations by the Arecibo Observatory reduced the inaccuracies in calculating the orbit by 50 percent. This improvement in values ​​resulted in the exclusion of a collision with the earth for the next hundred years. On April 22nd, the asteroid was therefore removed from the sentry list .

NASA also tracks the path of the object with the antennas of the Goldstone Deep Space Communications Complex and collects further data in a measurement campaign and the like. a. with the Green Bank , Very Large Array and Infrared Telescope Facility systems . (308635) 2005 YU ₅₅ was also observed with Herschel .

Its closest distance to Earth on the flyby in 2011 was (308635) 2005 YU ₅₅ on November 8th at 23:28 UT , with the asteroid passing the Earth at about 0.85 times the Earth-Moon distance. 0.85 lunar distances correspond to 0.00217 astronomical units (AU) or 325,000 km. The asteroid reached its closest proximity to the moon a few hours later, on November 9, 2011 at 07:13 UT, with 0.00160 AU (239,000 km). As it approached, the asteroid reached an apparent magnitude of 11 mag and could be observed by astronomers using precision binoculars with an 80 mm lens or larger.

The next known asteroid that is similarly close to Earth is (153814) 2001 WN ₅ . According to current calculations, it will fly past Earth at a distance of 0.00166 AU in 2028.

Future railway

On January 19, 2029, (308635) 2005 YU ₅₅ will pass Venus at a distance of approximately 0.0022 AU (329,000 km) . This approximation determines the distance at which asteroid 2041 will fly past Earth. The current inaccuracies in the calculation of the course after 2029 lead to a range of fluctuations in the distance at Passage 2041, which ranges from 0.002 AU (300,000 km) to 0.3 AU. The radar observations of the asteroid in November 2011 should provide more clarity about approaches to Earth in 2041 and later. According to measurements carried out on November 4, 2011, (308635) 2005 YU ₅₅ will even come close to Earth in 2075 to within 0.0013 AU (194,000 km).

See also

• List of asteroids
• List of near-earth asteroids

Web links

Commons : 2005 YU55  - Collection of Images, Videos, and Audio Files

• (308635) 2005 YU55 in the Small-Body Database of the Jet Propulsion Laboratory (English).
• 2005 YU55 Observing Campaign
• Arecibo saves us from another potentially hazardous asteroid (Emily Lakdawalla, April 29, 2010)
• NEODys page for 2005 YU55
• Page of the European Asteroid Research Node on 2005 YU55 ( Memento from December 11, 2011 in the Internet Archive )
• astronews.com: 2005 YU55 off near Earth Passage November 7, 2011

Videos

• Asteroid 2005 YU55 nasa.gov, accessed November 7, 2011
• First Movie of Asteroid 2005 YU55 , radar observation, nasa.gov, accessed November 9, 2011

Individual evidence

1. ↑ ^{a b c} (308635) 2005 YU55 in the Small-Body Database of the Jet Propulsion Laboratory (English).
2. ↑ MPEC 2005-Y47: 2005 YU55 . IAU Minor Planet Center. December 29, 2005. Retrieved May 5, 2011.
3. ↑ ^{a b c d e} Don Yeomans, Lance Benner and Jon Giorgini: Asteroid 2005 YU55 to Approach Earth on November 8, 2011 . NASA / JPL Near-Earth Object Program Office. March 10, 2011. Retrieved May 5, 2011.
4. ↑ ^{a b c} Blaine Friedlander Jr .: Arecibo telescope tracks 'potentially dangerous' asteroid within 1.5 million miles of Earth . Cornell Chronicle @ Cornell University. April 30, 2010. Retrieved May 5, 2011.
5. ↑ ^{a b c d e f} Dr. Lance AM Benner: 2005 YU55 Goldstone Radar Observations Planning . NASA / JPL Asteroid Radar Research. 2011 Oct 29. Retrieved October 30, 2011.
6. ↑ Date / Time Removed . NASA / JPL Near-Earth Object Program Office. Retrieved May 6, 2011.
7. ↑ NASA in Final Preparations for Nov. 8 Asteroid Flyby jpl.nasa.gov, accessed on November 4, 2011
8. ↑ Astronomers gear up for asteroid fly-by nature.com, November 2, 2011
9. ↑ Huge Asteroid to Creep Near Earth on Nov. 8 space.com, accessed November 7, 2011
10. ↑ 2005 YU55 resembles a raging scree slope mpg.de (accessed on January 12, 2012)
11. ↑ 2005YU55 Ephemerides for Nov 9, 2011 . NEODyS (Near Earth Objects - Dynamic Site). Retrieved May 5, 2011.
12. ↑ (308635) 2005 YU55 in the Small-Body Database of the Jet Propulsion Laboratory (English).