Asteroid 2005 YU55 is scheduled to pass within approximately 201,700 miles of the Earth on November 8, closer than the Moon’s orbit but further away than many other recent asteroid passes. However, 2005 YU55 is 1,300 feet across, making it the largest asteroid to pass the Earth since 1976, although it doesn’t pose any danger. The next known large asteroid to pass near Earth won’t happen until 2028.
Asteroid 2011 MD is expected to pass less than 8,000 miles above Earth’s surface on Monday, June 27. Closest approach will take place off the coast of Antarctica, but the asteroid may be visible from the Americas, the Pacific, and eastern Asia prior to its passage.
A 7 meter long asteroid, 2009 BD, passed within 346,000 kilometers of the Earth on June 2, coming inside the Moon’s orbit. Because 2009 BD is a co-orbital object, it will remain relatively close to the Earth for the next month or so, generally about 3,850,000 km away.
A small asteroid (2011 CQ1) discovered on February 3, passed around 7,500 miles from Earth on February 4 at 19:40 UT. This is about a quarter of the distance that 2010 TD54 passed by the Earth in October. 2011 CQ1 is between 1 and 2 metres across, making it smaller than a standard sofa. Had the asteroid hit Earth, it would have vaporized in the atmosphere.
The Voyager 1 space probe has entered the Heliosheath, an area where the solar wind drops to zero velocity. The heliosheath is the final region of our solar system and scientists believe that Voyager is within five years of crossing the heliopause, the edge of the solar system, and entering interstellar space. Scientists had previously thought Voyager was preparing to make the jump to interstellar space in 2005, but since the probe is in unknown territory, it is still sending back data which is changing astronomers’ models of the solar system. Launched in 1977, Voyager completed its mission to study the Jovian planets in 1989 when it passed Neptune. It is now located about 17.4 billion miles from Earth and is still sending back data.
A small asteroid (2010 TD54) passed around 28,000 miles from Earth on October 12, slightly higher than satellites in geosynchronous orbit. The asteroid, which was only about 6 meters in diameter, passed over Singapore around 6:50 EDT. Had the asteroid hit Earth, it would have vaporized in the atmosphere.
Astronomers have discovered the most hospitable exoplanet yet found orbiting the star Gliese 581, about 20 light years from Earth. The new planet has been named Gliese 581g, one of two additional planets discovered orbiting Gliese 581, brings that star’s system to six planets. Gliese 581g has a mass between 3 and 4 times that of Earth and orbits in the middle of the star’s habitable zone. The planet is believed to be tidally locked to its primary.
Asteroid 2010 RX30 passed within 154,000 miles of Earth at 5:51am ET on September 8. Approximately twelve hours later, at 5:12pm ET, asteroid 2010 RF12 is expected to pass within 49,088 miles of Earth. The asteroids are both estimated to be less than 70 feet in diameter and neither poses a threat to Earth. For comparison, the Moon is approximately 238,857 miles away.
Although astronomers created a definition for a Dwarf Planet in 2006, the definition only dealt with the upper size limit. Now, astronomers Charles Lineweaver and Marc Norman at the Australian National University in Canberra, have offered a definition for the lower end of dwarf planets, stating that a dwarf planet must have a circumference of at least 200 miles. Lineweaver and Norman selected that figure because anything larger will naturally form into a sphere, while anything small will retain a lumpier shape. The IAU has yet to debate and vote on the issue.
Scientists have announced that the dark plains on Saturn’s moon Titan will be named for planets in Frank Herbert’s six-volume series which began with the novel Dune. The first plain to bear an Herbertian name is Chusuk planitia, located at 5°S, 23.5°W. Chusuk was a planet reknowned for its fine musical instruments.