Category Archives: Asteroids
Remember when I mentioned that NASA’s OSIRIS-REx spacecraft was going to be scanning for “Trojan” asteroids at Earth-Sun L4? Well the results are in and survey says: no new Trojans (besides 2010 TK7, which we already knew about.) But the search wasn’t in vain—it gave mission scientists a chance put the spacecraft’s OCAMS instruments to the test and they passed with flying colors.
In fact the MapCam camera did so well it was able to image 17 main belt asteroids from L4, some two full magnitudes dimmer than expected.
“The Earth-Trojan Asteroid Search was a significant success for the OSIRIS-REx mission,” said OSIRIS-REx principal investigator Dante Lauretta of the University of Arizona, Tucson. “In this first practical exercise of the mission’s science operations, the mission team learned so much about this spacecraft’s capabilities and flight operations that we are now ahead of the game for when we get to Bennu.”
Read the full story on the OSIRIS-REx site here: OSIRIS-REx Asteroid Search Tests Instruments, Science Team
This image of the asteroid Eros—named after the Greek god of love—was captured on March 3, 2000, by NASA’s NEAR Shoemaker spacecraft. It’s actually a mosaic of six separate images acquired from a distance of 127 miles from the 20-mile-wide asteroid, and reveals many large boulders scattered across the surface down to about 160 feet in size. The ubiquitous boulders on Eros are believed to be fragments of its own native rock, shattered by countless impact events over time.
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:
It sounds like a surprise challenge posed by the “Dungeon Master” in a game of Dungeons & Dragons but this is sort of what happened on a cosmic scale on Feb. 6, 2017, when the 200-meter (656-foot) -wide asteroid 2017 BQ6 passed by Earth. Using the radar imaging capabilities of the giant 70-meter antenna at NASA’s DSN facility in Goldstone, CA, scientists got a good look at the object as it passed—and it does seem to resemble a tumbling gaming die!
“The radar images show relatively sharp corners, flat regions, concavities, and small bright spots that may be boulders,” said Lance Benner of NASA’s Jet Propulsion Laboratory in Pasadena, California, who leads the agency’s asteroid radar research program. “Asteroid 2017 BQ6 reminds me of the dice used when playing Dungeons and Dragons. It is certainly more angular than most near-Earth asteroids imaged by radar.”
Launched on Sept. 8, 2016, NASA’s OSIRIS-REx spacecraft is heading out into the main asteroid belt beyond the orbit of Mars to meet up with the 1,600-foot-wide asteroid Bennu. Ultimately OSIRIS-REx will map and collect a sample of Bennu’s surface, returning it to Earth in 2023. But while it’s still traveling through near-Earth space in preparation for a gravity-assist flyby this September, mission scientists will take advantage of OSIRIS-REx’s position near L4 to look for any captured “Trojan” asteroids.