A team of NASA scientists have measured the weight and orbit of 1999 RQ36. They have found the asteroid has a low density and its orbit has drifted roughly 100 miles in the last 12 years. This deviation is caused by the Yarkovsky effect. This effect can either push an asteroid into the Earth's orbit.... or away.
This puts an interesting twist on NEOs (Near Earth Objects) that I recently blogged about here.
This team's work using NASA's Spitzer Space Telescope in 2007 was crucial in determining the effect. They measured the asteroid's thermal characteristics using infrared emissions and determined the space rock was covered in an insulating blanket of fine material -- a key factor for the effect.
The Yarkovsky effect sharpens the picture of how potentially hazardous 1999 RQ36 could be in the future. The 1,640-foot-diameter asteroid is expected to pass by Earth in 2135 at around 220,000 miles. At such close distances, the asteroid's subsequent trajectory becomes impossible to predict accurately so close approaches can only be studied statistically. Imagine if this effect pushes it closer to the Earth or even causes it to be on a collision course with the Earth!
Due to this discovery, scientists now have identified many low-probability potential impacts in the 2170s through the 2190s while ruling out others.
The Yarkovsky effect is named for the 19th-century Russian engineer who first proposed the idea that a small rocky space object would, over long periods of time, be noticeably nudged in its orbit when it absorbs sunlight and then re-emits that energy as heat. The effect is difficult to measure because it's so infinitesimally small.
The effect was discovered on 1999 RQ36 in an effort to determine the mass of the asteroid from millions of miles away. The scientists needed the space rock's size, thermal properties, propulsive force (Yarkovsky effect) and orbit to calculate the bulk density.
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Last night, a solar storm interacted with the Earth's magnetosphere, setting off a cosmic light show for those in high latitudes.
Several meteor showers are yet to come during the last few months of 2016. There will be some eclipses as well as beautiful planetary alignments!
Early on Thursday morning there will be a lunar eclipse, but it will go by largely unnoticed.
The 2016 Perseids have lived up to the hype. They have been very bright with most leaving trails. A secondary peak should keep activity strong through tonight.
Tonight's Perseid's meteor shower will put on quite a show. It will be the most impressive shower of 2016, if not the past several years. This is your complete guide to viewing the 2016 Perseids.
The 2016 Perseids may turn out to be the most active meteor shower since the Leonids in the early 2000s. This is your complete guide to the shower including forecast sky conditions maps for around the globe.