SJAA Ephemeris February 2013 | SJAA Home | Contents | Previous | Next

The Last Month in Astronomy


JAN-13-2013 • Planet Hunters • The Zooniverse project overseas the Planet Hunters project which uses dedicated amateurs to find planets otherwise hidden in Kepler data. The latest announcement is that 42 new planets have been discovered by the Planet Hunters. Some of these planets are in the habitable zone and may include Avatar-like moons, moons around large planets that could harbor life.

JAN-09-2013 • Apophisizing • The asteroid Apophis recently passed near Earth. This asteroid was one time thought to have a 2.7% change of impacting Earth in 2029. Then that was reduced to 0 and the year 2036 seemed possible. Now it looks like 2036 and every other year within a reasonable timeframe has a virtually 0% chance. In addition, the Herschel spacecraft took new observations that sets the size of Apophis to be 325 meters compared to previous estimates of 270 meters. In addition, the albedo of Apophis is .23 which is less than the previous measurement of .33.

JAN-09-2013 • Farthest Supernova • Astronomers at Berkeley have set a record for the most distant Type 1a Supernova. Now called SN SCP-0401, the supernova has a redshift of 1.71 which corresponds to a lookback time of 10 billion years. According to David Rubin from Berkeley Lab “The most important unanswered question we have about the nature of dark energy is whether it varies over time ... we have the first example of a well-measured supernova sufficiently far away to study the expansion history of the universe from almost 10 billion years ago.”

JAN-08-2013 • Warm and cold belts • The star Vega appears to have two asteroid belts, one cold and one warm. This makes it similar to two other stars. One of those stars is Fomalhaut. The other is one that you know well, the Sun. The sun’s warm asteroid belt is that one we actually call “the” asteroid belt and the cold belt is the Kuiper belt. The cold belt is 10 times further away than the warm belt in all 3 stars. It is likely that all 3 stars have multiple Jovian-class planets between the warm and cold belts but we are only certain about one of them.

JAN-07-2013 • Kepler strikes again • The Kepler project has announced the discovery of 461 new planet candidates. These candidates come from observations made between May 2009 and March 2011. The new candidates show that more stars with multiple planets are being found. Also, the number of smaller planet candidates is increasing. 4 of the candidates are less than 2 earth masses and orbit within the expected habitable zone.

JAN-04-2013 • Watery Mars Meteorite • A meteorite found in Northwest Africa was formed 2.1 billion years ago on Mars. The meteorite is a better match to rocks studied by Mars rovers than it is to other Martian meteorites. It has a high water content.

DEC-19-2012 • Ultramassive Black Holes • A new survey of 18 galaxy clusters has found at least 10 ultramassive black holes. Black holes in this category have 10 to 40 billion solar masses. Andrew Fabian (Cambridge University) says “These results may mean we don’t really understand how the very biggest black holes coexist with their host galaxies.” The assumption is that these ultramassive black holes must behave very differently from their smaller counterparts.

DEC-17-2012 • GRAIL Impact • The NASA GRAIL (Gravity Recovery and Interior Laboratory) mission was completed when it impacted the moon on December 17th. The impact site was immediately named for Sally K. Ride. The data from GRAIL will takes years to analyze. The two spacecraft, named Ebb and Flow, entered lunar orbit on New Years Day of 2012 after a launch in September of 2011.

DEC-13-2012 • Distant Microquasar Found • A microquasar is powered by a stellar size black hole devouring material from a companion star. These have only been found in the Milky Way, until now. A microquasar has been found in the Andromeda galaxy. The mechanism at work in these microquasars are thought to be similar to quasars found in active galactic nuclei. However, the processes within the microquasar are more dynamic. Also, finding them in other galaxies is a boon to astronomers because the microquasars in the Milky Way galaxy occur in the galactic disk and are thus obscured by dust, gas and other stars.


Previous | Contents | Next