Something awfully curious is happening 250 million miles away

[Mike]

Something awfully curious is happening 250 million miles away in the asteroid belt.

Astronomers think they may be witnessing a never-before-seen collision between two asteroids.

The puzzle centers on a newly discovered object that superficially looks like a comet but lives among the asteroids.

The strange object was discovered on January 6 by the Lincoln Near-Earth Asteroid Research (LINEAR) sky survey. The object appears to be in an orbit inside the main asteroid belt -- not a place where comets usually dwell.

The distinction? Comets swoop along elliptical orbits close in to the sun and grow long gaseous and dusty tails as ices sublimate off their solid nucleus and release dust. But asteroids are mostly in more circular orbits and are not normally expected to be as volatile as comets.

MORE..... http://news.discovery.com/space/mystery-object-behaves-both-like-a-comet-and-asteroid.html

[Tony G]

NASA's Hubble Space Telescope has observed a mysterious X-shaped debris pattern and trailing streamers of dust that suggest a head-on collision between two asteroids. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before.

http://science.nasa.gov/headlines/y2010/02feb_asteroidcollision.htm?list6979

Tony G

[mickw]

And some more:

space.com

[Tony G]

And some more. Today's APOD

http://antwrp.gsfc.nasa.gov/apod/ap100203.html

Tony G

[Rick]

Comet Found Hiding in Plain Sight

For 30 years, a large near-Earth asteroid wandered its lone, intrepid path, passing before the scrutinizing eyes of scientists armed with telescopes while keeping something to itself. The object, known as Don Quixote, whose journey stretches to the orbit of Jupiter, now appears to be a comet.

The discovery resulted from an ongoing project coordinated by researchers at Northern Arizona University, Flagstaff, Ariz., using NASA's Spitzer Space Telescope. Through a lot of focused attention and a little luck, they found evidence of comet activity, which had evaded detection for three decades.

More: http://www.jpl.nasa.gov/news/news.php?release=2013-274

[Rick]

First Ring System Around Asteroid

Observations at many sites in South America, including ESO's La Silla Observatory, have made the surprise discovery that the remote asteroid Chariklo is surrounded by two dense and narrow rings. This is the smallest object by far found to have rings and only the fifth body in the Solar System — after the much larger planets Jupiter, Saturn, Uranus and Neptune — to have this feature. The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris. The new results are published online in the journal Nature on 26 March 2014.

More: http://www.eso.org/public/news/eso1410/

[Rick]

Main-Belt Asteroid Shows Evidence of March Collision

The main-belt asteroid (493) Griseldis was probably hit by another object last March. The results were reported on November 12 at the annual meeting of the Division for Planetary Sciences of the American Astronomical Society near Washington, DC.

Observations taken with the 8-meter Subaru Telescope on Maunakea on 17 March 2015 UT showed that the main-belt asteroid (493) Griseldis had "an extended feature," which is astronomer-speak for a tail.

More: http://www.ifa.hawaii.edu/info/press-releases/493Griseldis/

[Rick]

A 'Tail' of Two Comets

Two comets that will safely fly past Earth later this month may have more in common than their intriguingly similar orbits. They may be twins of a sort.

Comet P/2016 BA14 was discovered on Jan. 22, 2016, by the University of Hawaii's PanSTARRS telescope on Haleakala, on the island of Maui. It was initially thought to be an asteroid, but follow-up observations by a University of Maryland and Lowell Observatory team with the Discovery Channel Telescope showed a faint tail, revealing that the discovery was, in fact, a comet. The orbit of this newly discovered comet, however, held yet another surprise. Comet P/2016 BA14 follows an unusually similar orbit to that of comet 252P/LINEAR, which was discovered by the Massachusetts Institute of Technology's Lincoln Near Earth Asteroid Research (LINEAR) survey on April 7, 2000. The apparent coincidence may be an indication of twin nature in that comet. P/2016 BA14 is roughly half the size of comet 252P/LINEAR and might be a fragment that calved off sometime in the larger comet's past.

More: http://neo.jpl.nasa.gov/news/news191.html

[Rick]

Comet Flying by Earth Observed with Radar and Infrared

Astronomers were watching when comet P/2016 BA14 flew past Earth on March 22. At the time of its closest approach, the comet was about 2.2 million miles (3.5 million kilometers) away, making it the third closest comet flyby in recorded history (see "A 'Tail' of Two Comets" above...). Radar images from the flyby indicate that the comet is about 3,000 feet (1 kilometer) in diameter.

The scientists used the Goldstone Solar System Radar in California's Mojave Desert to track the comet. "We were able to obtain very detailed radar images of the comet nucleus over three nights around the time of closest approach," said Shantanu Naidu, a postdoctoral researcher at NASA's Jet Propulsion Laboratory in Pasadena, California, who works with the radar team and led the observations during the comet's flyby. "We can see surface features as small as 8 meters per pixel.

More: http://www.jpl.nasa.gov/news/news.php?feature=6180

[Rick]

Hubble Catches Views of a Jet Rotating with Comet 252P/LINEAR

Astronomers using NASA's Hubble Space Telescope captured images of Comet 252P/LINEAR just after it swept by Earth on March 21. The visit was one of the closest encounters between a comet and our planet. The comet traveled within 3.3 million miles of Earth, or about 14 times the distance between our planet and the moon. The images reveal a narrow, well-defined jet of dust ejected by the comet's icy, fragile nucleus. These observations also represent the closest celestial object Hubble has observed, other than the moon. The comet will return to the inner solar system again in 2021.

More: http://hubblesite.org/newscenter/archive/releases/2016/14