Category Archives: Comets and Asteroids
NASA’s OSIRIS-REx may be designed to study asteroids close up but recently it’s captured a view of something farther away and much, much larger: the giant planet Jupiter and three of its largest moons at a distance of over 400 million miles!
The image was taken on Feb. 12, 2017, when the spacecraft was 76 million miles (122 million km) away from Earth—near the Earth-Sun L4 point—and 418 million miles (673 million km) from Jupiter. It’s a combination of two images taken with the PolyCam instrument, OSIRIS-REx’s longest range camera, which will capture images of the asteroid Bennu from a distance of over a million miles.
Read the full article here: NASA’s OSIRIS-REx Takes Closer Image of Jupiter
Four years ago today an explosion shattered the morning sky over the Chelyabinsk region in southwestern Russia, the result of a 60-foot-wide fragment of an asteroid entering Earth’s atmosphere at over 40,000 mph and brilliantly blowing itself to smithereens at 97,000 feet up. Even at that altitude, the resulting flash of light and air blast was powerful enough to cause extensive damage on the ground, shattering windows, knocking in doors, and causing injury to nearly 1,500 people across towns in the area—several of them seriously.
This was the largest observed meteor since the famous 1908 Tunguska event, but thanks to the prevalence today of dashboard and CCTV cameras in Russia this one was well-recorded. (I remember seeing the videos online within an hour after it happened!) The footage has allowed scientists to not only determine the energy of the Chelyabinsk meteor explosion—about 500 kilotons—but also the object’s trajectory and origin.
Watch a video below of footage captured from various locations of the Chelyabinsk meteor:
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.