Why Are Particles Getting Ejected Off of Asteroid Bennu?

NASA’s OSIRIS-REx spacecraft arrived at asteroid Bennu in December 2018, and just one week later, it discovered something unusual about Bennu: the asteroid was ejecting particles into space.

The spacecraft’s navigation camera first spotted the particles, but scientists initially thought they were just stars in the background. After closer scrutiny, the OSIRIS-REx team realized they were particles of rock, and were concerned that they might pose a hazard.

Continue reading “Why Are Particles Getting Ejected Off of Asteroid Bennu?”

It’s Time to Decide. Where Should OSIRIS-REx Take a Sample from Bennu?

NASA’s OSIRIS-REx arrived at asteroid Bennu in December 2018. During the past year, it’s been imaging the surface of the asteroid extensively, looking for a spot to take a sample from. Though the spacecraft has multiple science objectives, and a suite of instruments to meet them, the sample return is the key objective.

Now, NASA has narrowed the choice down to four potential sampling locations on the surface of the asteroid.

Continue reading “It’s Time to Decide. Where Should OSIRIS-REx Take a Sample from Bennu?”

The Large Synoptic Survey Telescope Could Find More of Earth’s Transient Moons

One of the many PHOs (Potentially Hazardous Objects) that we're keeping an eye on. Image Credit: NASA

It is a well-known astronomical convention that Earth has only one natural satellite, which is known (somewhat uncreatively) as “the Moon”. However, astronomers have known for a little over a decade that Earth also has a population of what are known as “transient Moons”. These are a subset of Near-Earth Objects (NEOs) that are temporarily scooped up by Earth’s gravity and assume orbits around our planet.

According to a new study by a team of Finish and American astronomers, these temporarily-captured orbiters (TCOs) could be studied with the Large Synoptic Survey Telescope (LSST) in Chile – which is expected to become operational by 2020. By examining these objects with the next-generation telescope, the study’s authors argue that we stand to learn a great deal about NEOs and even begin conducting missions to them.

Continue reading “The Large Synoptic Survey Telescope Could Find More of Earth’s Transient Moons”

Comets and Interstellar Objects Could be Exporting Earth Life Out into the Milky Way

For over a century, proponents of Panspermia have argued that life is distributed throughout our galaxy by comets, asteroids, space dust, and planetoids. But in recent years, scientists have argued that this type of distribution may go beyond star systems and be intergalactic in scale. Some have even proposed intriguing new mechanisms for how this distribution could take place.

For instance, it is generally argued that meteorite and asteroid impacts are responsible for kicking up the material that would transport microbes to other planets. However, in a recent study, two Harvard astronomers examine the challenges that this would present and suggest another means – Earth-grazing objects that collect microbes from our atmosphere and then get flung into deep-space.

Continue reading “Comets and Interstellar Objects Could be Exporting Earth Life Out into the Milky Way”

This Summer’s Asteroid Near-Miss Helped Greenlight NASA’s NEOCam Mission to Search the Skies for Killer Spacerocks

NEO asteroid

Last July, a once-in-a-lifetime event happened. Not the good kind; the football-field-sized-asteroid near-miss kind. And that near miss is the catalyst for a renewed effort from NASA to detect more dangerous space-rocks that might threaten Earth.

Last summer’s near-miss asteroid was named 2019 OK, and it passed within about 77,000 km (48,000 miles) of Earth. It managed to slip past all of our detection methods and came within 0.19 lunar distances to Earth. In astronomical terms, that is remarkably close.

We only had 24 hours notice that the asteroid was coming, thanks to a small telescope in Brazil that spotted it. That near miss has sparked a renewed conversation on planetary defense and on NASA’s role in it.

It also left people wondering how this could happen.

Continue reading “This Summer’s Asteroid Near-Miss Helped Greenlight NASA’s NEOCam Mission to Search the Skies for Killer Spacerocks”

Hayabusa 2 has one Last Lander it’s Going to Throw at Ryugu

On June 27th, 2018, the Japanese Aerospace Exploration Agency‘s (JAXA) Hayabusa2 spacecraft reached asteroid 162173 Ryugu. As part of JAXA’s program to study Near-Earth Asteroids (NEAs), this mission has spent over a year conducting landing operations, shooting up the surface with “bullets” and an anti-tank warhead, and collecting samples from the surface and interior that will eventually be returned to Earth.

This past Monday (Sept. 16th), Hayabusa2 released two target markers as part of its “target marker separation operation” (which ran from Sept. 12th to Sept. 17th). This consisted of two 10 cm (4 in) balls covered in reflective material being released in orbit around Ryugu. This operation puts the mission a step closer to the deployment of the mission’s MINERVA-II2 Rover-2, which will be landing on the asteroid’s surface next month.

Continue reading “Hayabusa 2 has one Last Lander it’s Going to Throw at Ryugu”

A Distant Asteroid Collision Gave Earthly Biodiversity An Ancient Boost

About 466 million years ago, there was an asteroid collision in the asteroid belt between Mars and Jupiter. The collision caused the breakup of a major asteroid, creating a shower of dust throughout the inner Solar System. That event is called the Ordovician Meteor Event, and its dust caused an ice age here on Earth.

That ice age contributed to an enormous boost in biodiversity on ancient Earth.

Continue reading “A Distant Asteroid Collision Gave Earthly Biodiversity An Ancient Boost”