The Tunguska Explosion Could Have Been Caused By An Asteroid That Still Orbits The Sun

On a cool Summer morning in 1908, a fireball appeared over Northern Siberia. Eyewitnesses described a column of blue light that moved across the sky, followed by a tremendous explosion. The explosion leveled trees across more than 2,000 square kilometers. The explosion is consistent with a large meteor strike, but to this day no evidence of a crater has been found. Now known as the Tunguska Event, its cause remains a mystery to this day.

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OSIRIS-REx Descended Down to Just 75 Meters Above the Surface of Bennu in a Recent Test

NASA’s OSIRIS-REx spacecraft is getting ready for its big moment. OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) is at asteroid Bennu, preparing to collect a sample of ancient rock. And collecting that sample means taking step after meticulous step.

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These are the Boulders OSIRIS-REx is Going to Use to Navigate Down to the Surface of Bennu

Meet OSIRIS-REx’s “Guide Boulders.”

When the NASA spacecraft first arrived at asteroid Bennu over a year ago, the surface of the asteroid was much different than expected. Instead of a surface with large, smooth areas, nearly the entire surface is covered in boulders. That meant that NASA had to do a re-think of the sampling procedure.

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Asteroid Bennu is Getting Some Official Names for its Surface Features

Late last summer, NASA and the International Astronomical Union’s Working Group for Planetary System Nomenclature (a.k.a WGPSN) approved the naming convention for features on Bennu, the asteroid currently being orbited and studied by the OSIRIS-Rex spacecraft. The naming theme chosen was “birds and bird-like creatures in mythology.”

The first twelve features thusly named have now been announced. But more importantly, some of these features will be instrumental in helping to guide OSIRIS-REx to the surface of the asteroid later this year.

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OSIRIS-REx did its Closest Flyover Yet, just 250 Meters Above its Sample Site

NASA’s OSIRIS-REx is getting closer, physically and temporally, to its primary goal. The spacecraft arrived at Bennu at the end of 2018, and for just over a year it’s been studying the asteroid, searching for a suitable sampling site. To do that, it’s getting closer and closer.

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Even Though it Was Observing an Asteroid, OSIRIS-REx Accidentally Spotted a Black Hole

While the OSIRIS-REx spacecraft was orbiting asteroid Bennu, one of the instruments on board happened to catch a glimpse of a black hole ‘out of the corner of its eye,’ so to speak.

While intently focusing on the asteroid, the Regolith X-Ray Imaging Spectrometer (REXIS) happened to catch the X-rays from a newly flaring stellar mass black hole.  While the flare occurred 30 thousand light years away, the flash in distant space was visible just off the limb of asteroid Bennu, in the edge of the instrument’s field of view.

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Astronomers Discover a Tiny New Temporary Moon for the Earth. Welcome to the Family 2020 CD3

Astronomers are increasingly interested in Near-Earth Objects, or NEOs. There are ongoing efforts to find them all and catalog them all, and to find out which ones might pose a collision threat. Now some astronomers with the NASA-funded Catalina Sky Survey have found a new, tiny, temporary moon for Earth.

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New Images of the “Golf Ball” Asteroid Pallas

In 1802, German astronomer Heinrich Olbers observed what he thought was a planet within the Main Asteroid Belt. In time, astronomers would come to name this body Pallas, an alternate name for the Greek warrior goddess Athena. The subsequent discovery of many more asteroids in the Main Belt would lead to Pallas being reclassified as a large asteroid, the third-largest in the Belt after Ceres and Vesta.

For centuries, astronomers have sought to get a better look at Pallas to learn more about its size, shape, and composition. As of the turn of the century, astronomers had come to conclude that it was an oblate spheroid (an elongated sphere). Thanks to a new study by an international team, the first detailed images of Pallas have finally been taken, which reveal that its shape is more akin to a “golf ball” – i.e. heavily dimpled.

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OSIRIS-REx Flew 620 Meters Above its Landing Site. Confirms that it’s a Boulder-Strewn Nightmare, Just Like the Rest of Bennu

NASA’s OSIRIS-REx spacecraft reached its target, asteroid Bennu (101955 Bennu), on December 3rd, 2018. Since then, the spacecraft has been examining the asteroid’s surface, looking for a suitable landing spot to collect a sample. The problem is, Bennu has a much rockier and challenging surface than initially thought.

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