2007 WD 5

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Asteroid
2007 WD 5
Properties of the orbit ( animation )
Orbit type Near-Earth asteroid
Major semi-axis 2.54  AU
eccentricity 0.603
Perihelion - aphelion 1.01016 AU - 4.07 AU
Inclination of the orbit plane 2.37 °
Sidereal period 4.05 a
Mean orbital velocity 18.69 km / s
Physical Properties
Medium diameter 50 m
Dimensions ? Template: Infobox asteroid / maintenance / masskg
Albedo ?
Medium density ? g / cm³
Rotation period ?
Absolute brightness 24.308 likes
Spectral class ?
history
Explorer Catalina Sky Survey
Date of discovery November 20, 2007
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.

2007 WD 5 is a near-Earth asteroid discovered by the Catalina Sky Survey on November 20, 2007 . Its elliptical orbit extends beyond the orbit of Mars into the main asteroid belt . Its orbit closest to the sun, however, is just inside the earth's orbit. The perihelion is a little more than an astronomical unit , but it still crosses the earth's elliptical orbit. He belongs to the group of Apollo asteroids . With its diameter of around 50 meters, it is a relatively small object. Nevertheless, it was observed more closely because its orbit runs close to Earth. Further observations gave scientists enough data to determine that the asteroid posed no threat to Earth.

Possible collision with Mars

Possible collision with Mars

When determining the orbit, however, it was determined that it might hit Mars . A close encounter occurred on January 30, 2008 at approximately 12 noon UTC . According to the latest orbital data, however, it most likely did not hit the red planet. He flew past the center of the planet at a distance of 26,000 kilometers. That means a distance of about seven Mars radii from the surface. However, even according to the latest calculations, there was still a 0.01% chance that WD 5 would hit Mars in 2007 , as there were still uncertainties about the asteroid's exact orbit. In the meantime, higher collision probabilities of up to 4% (or 1 in 25) have also been calculated.

Such a collision would have created a crater about 800 meters in diameter. In 1908 in Tunguska, Siberia , a similarly sized asteroid is said to have collided with the earth. This did not create a crater, however, as the object dissolved in the dense earth's atmosphere before it hit the ground. The Martian atmosphere is much thinner than that of Earth, which is why it would reach the ground there.

Scientists hoped to be able to observe this event and its consequences with various Mars probes. Mars Express of the ESA and Mars Reconnaissance Orbiter in orbit, and the rovers Spirit and Opportunity on the surface of Mars (all three NASA ) would have had the best opportunities.

See also

Web links

Individual evidence

  1. ^ NASA Near-Earth Object Program , January 9, 2008