Category Archives: Comets and Asteroids
Astronomers are always watching the skies for observations of near-Earth asteroids—”space rocks” that have orbits close to Earth’s and, in the case of potentially hazardous asteroids (aka PHAs), those whose orbits could actually cross Earth’s and are larger than 150 meters (500 ft) across. When a new one of these is discovered—no small feat considering that many are very dark, move quickly, and could really be anywhere in the sky—it’s a scramble to determine the object’s orbital parameters and figure out just how close it can get to us and when. Such was the case on Oct. 19, 2016, when the asteroid 2016 WJ1 was identified with the Catalina Sky Survey. This object, estimated to be anywhere from 110 to 340 meters across—easily within the potentially hazardous range—was initially calculated to pose a threat in 2065 with a possible impact risk, albeit a very small one. Eventually though, scientists were able to refine the risk chance with more observations of 2016 WJ1…observations that had actually occurred over 13 years earlier.
Read the full story from ESA here: Asteroid sleuths go back to the future
Happy New Year! Just four days into 2017 NASA announced its pick for two new Discovery missions to explore our solar system: one to investigate a few of the “Trojan” asteroids that Jupiter has gathered into its orbit with its mighty gravity, and another to visit the remains of an ancient planet’s metallic core!
“These are true missions of discovery that integrate into NASA’s larger strategy of investigating how the solar system formed and evolved,” says Jim Green, NASA’s Planetary Science Director. “We’ve explored terrestrial planets, gas giants, and a range of other bodies orbiting the sun… These additional pieces of the puzzle will help us understand how the sun and its family of planets formed, changed over time, and became places where life could develop and be sustained – and what the future may hold.”
Find out these new missions’ names, launch dates, and more below:
Rosetta is down. I repeat: Rosetta is down.
This morning, Sept. 30, 2016, just after 10:39 UTC (6:39 a.m. EDT) ESA’s Rosetta spacecraft ended its mission with an impact onto the surface of the comet 67P/Churyumov-Gerasimenko. The descent, begun with a final burn of its thrusters about 14 hours earlier, was slow, stately, and deliberate, but even at a relative walking pace Rosetta was not designed to be a lander like its partner Philae and thus ceased operation upon contact with the comet.
With the comet 446 million miles (719 million km) from Earth at the time, the final signals from Rosetta were received 40 minutes after impact, officially confirming mission end.