SJAA Ephemeris October 2010 | SJAA Home | Contents | Previous | Next

The Last Month in Astronomy

Windy Galaxy


16-SEP-2016 •LRO turns to Science• The exploration phase of the Lunar Reconnaissance Orbiter has completed. It will now turn to scientific research and continue mapping the moon from its polar orbit 31 miles above the surface. Program management moves from NASA’s Exploration Systems Mission Directorate to the Science Mission Directorate. LRO was launched on June 18, 2009 and began it’s detailed survey in September of 2009. The findings from the mission include permanently shadowed regions that may harbor water and be colder than Pluto. It made observations of Apollo landing sites and found the lost Russian rover Lunokhod which had one of those retroreflectors which can be used to bounce laser signals. Any viewer of the TV show “The Big Bang Theory” already knows this. After getting an accurate position on the Lunokhod a laser signal bounce was successful, 40 years after the rover was lost.

09-SEP-2010 •Fireballs on Jupiter• In a paper published in the Astrophysical Journal Letters, a group of professional and amateur astronomers pointed out that Jupiter is getting hit by asteroids at a surprisingly high rate. It has only been in the last two years that amateurs have shown they can detect these strikes. The most recent hit occurred August 20th. Earth gets his with a 10-meter object once a decade. But it looks like Jupiter gets a similar hit a few times each month. A 10-meter object passed close to Earth on September 8th. A slightly smaller rock, 2008 TC3, burned up in the atmosphere above Sudan 2 years ago.

01-SEP-2010 •Windy Galaxy• The galaxy NGC 4666 is a starburst galaxy, a location of heavy star formation, that is estimated to be 80 million light-years from Earth. The star making activity is probably caused by interaction with NGC 4668. This activity leads to the formation of large stars and those stars die young and create supernovae. The result is a lot of gas, a “superwind”, that flows out of the galaxy. This image was taken with the Wide Field Imager on the MPG/ESO 2.2 meter telescope at the La Silla Observation in Chile. It was used as a follow up on an X-ray image taken by the XMM-Newton space telescope.

01-SEP-2010 •Making Water• Quick, what do you need to create water? Best guess, cosmically speaking, is ultraviolet light. That is what some recent evidence from the Herschel spacecraft suggests. Paul Goldsmith from NASA says “These Herschel observations confirm the surprising presence of water vapor in what we thought was an astronomical desert.” Herschel is a European Space Agency mission but NASA is a major participant via JPL.

01-SEP-2010 •Magnesium at Mercury• The MESSENGER spacecraft has detected magnesium in the exosphere of Mercury. It was expected to be most highly concentrated at the surface and then tail off exponentially. Instead, the concentration over the north pole “was hanging there at a constant density, and then all of a sudden, it dropped like a rock” according to Rosemary Killen (Goddard). The temperature in this area is many times higher than the highest surface temperature. This requires some high-energy process that is completely unknown at this time.

20-AUG-2010 •Confirmation Cosmological• Some observations of the gravitational lensing seen in Abell 1689 have increased confidence in the cosmological model most astronomers accept. That model says that dark energy makes up about 72% of the universe, dark matter about 23% and normal (baryonic) matter only 5%.

19-AUG-2010 •Moon shrinking• The moon has been shrinking recently. Note that in this case “recent” means sometime in the last 1 billion years. That’s important because it was thought that small bodies like the moon would completely cool and stop shrinking within 1, 2 or 3 billion years after they were formed. It is not known if the moon will shrink more but it will stop eventually.


Previous | Contents | Next