scientists finetune odds asteroid hitting

'That was enough to give us a strong detection of the Yarkovsky effect, which is something we've been expecting to see now for a while.' 'We really nailed the position of this asteroid extremely well,' Tholen said. (A milliarcsecond is a thousandth of an arcsecond, an angular measurement that helps scientists measure cosmic distances.) The researchers collected 18 exposures of the asteroid at a very high precision, with an error of only 10 milliarcseconds in each observation. Tholen's team made the discovery after four nights of observation in January and March with the Subaru Telescope, a Japanese optical-infrared telescope on the summit of Maunakea, Hawaii. We'll know after that occurs exactly where it was as it passed the Earth, and that will make it much easier for us to predict future impact scenarios.' 'Of all dates, Friday the 13th in April, April 13, is when the flyby will occur,' Tholen said., 'Obviously, the 2029 close approach is critical. Apophis will be so close it will be visible with the naked eye, at third magnitude - about as bright as the binary star Cor Caroli. 'We need to track this asteroid very carefully.'įortunately, the asteroid will make a close (yet still safe) approach to our planet in 2029, allowing ground-based telescopes - including the Arecibo Observatory's powerful radar dish - to get a more detailed look at the asteroid's surface and shape. 'The 2068 impact scenario is still in play,' Tholen said. Ultimately, this means we can't yet rule out Apophis being a threat in 2068, Tholen said. Those calculations, however, were based on an orbit not affected by the sun's energy. Showing the orbit for the 1,120-foot-wide (340 m) Apophis, he indicated that astronomers thought they had enough observations of the asteroid - collected over the years after its discovery in 2004 - to more or less rule out an impact in 2068. 'The warmer hemisphere would be pushing slightly more than the cooler hemisphere, and that causes the asteroid to drift away from what a purely gravitational orbit would predict,' Tholen said. You can find the press conference on YouTube here. 'Basically, the heat that an asteroid radiates gives it a very tiny push,' he explained during a virtual meeting of the American Astronomical Society's Division for Planetary Sciences.

Scientists finetune odds asteroid hitting