Happy Friday! I hope you remembered to wear red today for Women's Heart Disease awareness! There have been some interesting developments with Comet Lulin the past couple of days, has anyone had the chance to see it? Another exoplanet has been discovered, but this one is extra special! Meanwhile, some new information is available about an asteroid explorer and a beautiful galaxy cluster.

Check This Out!

Comet Lulin continues to make its presence known in the early morning sky. Not only is the beautiful object getting closer to Earth, but it seems to have had a run-in with the solar wind, and it lost part of its tail! There are several great pictures and some video of the event on spaceweather.com. This morning, the comet passed very near the Libra star Zubenelgenubi (say that three times fast). This double star, also known as Alpha Librae, shines at around magnitude 2.75 and is considered a "naked eye double" much like Mizar and Alcor in Ursa Major. Zubenelgenubi and its companion are both about 77 light-years away, but both fall into different star classes. One is more like our own sun, while the other is a warmer white star.

Location of Comet Lulin Near Zubenelgenubi-Starry Night/Main Sequence

I mentioned on Monday that this month is the best for viewing asteroid Ceres (see Monday's entry for sky map), so be sure not to miss out on that one. Today, Asteroid 6433 Enya will pass within 130,045,174 miles of Earth. This asteroid is named after one of my favorite musicians, Enya, who is known for songs such as "Only Time" and "Orinoco Flow (Sail Away)".

For those of you who are interested in the Cassini mission, the latest update is that the craft will pass by Saturn's moon, Titan, on the 7th. Cassini will pass within about 597 miles of the moon around 3am eastern time. The craft continues to make passes by Saturn and several of its moons, and has taken some amazing pictures, including one that shows a partial map of Titan.

Saturn's rings and a few moons-NASA/Cassini

Map of Titan-NASA/Cassini

Astronews!

The CoRoT satellite just discovered an extrasolar planet only slightly larger than Earth! It is not yet know whether the planet is rocky or lava covered, but the fact that a planet close to the size of Earth has been found is a huge deal. Most exoplanets to date have been described as "hot Jupiters" because they are around the size of the giant planet. The "super-Earth" planet, named CoRoT-Exo-7b, zips around its parent star in just 20 days and is very close to its parent star. That fact alone tells us that it is too hot to sustain life; the temperature is estimated to be between 1800 and 2700F. The planet was detected because as it passed in front of its star, the brightness of the star was seen to decrease slightly. To date, Exo-7b is the smallest transiting exoplanet known. There are now over 330 extrasolar planets known, and only a handful are estimated to be close to the size of Earth, Venus or Mercury. Scientists have yet to find an exoplanet that shows evidence of supporting liquid water, or for that matter, life.

The Japanese Asteroid Explorer craft, Hayabusa (not the sports bike, sorry, Jon), was leaving orbit around the asteroid Itokawa in October, 2007 when its engine suddenly stopped working. Since then, the craft has been coasting around the asteroid; however, earlier today, the Japan Aerospace Exploration Agency was able to get the engine working again. The team from JAEA has been gradually accelerating the craft and will continue to do so until about March, 2010, at which point the second phase of the orbit maneuvering will be activated. This maneuver, if successful, will give the craft the push it needs to send it back towards Earth. Between April and June, 2010, Hayabusa will be guided closer to the Earth's orbit, with re-entry planned for June. Fortunately, Hayabusa still has enough propellant and thrust power to keep moving and get back to Earth if everything continues to function properly.

An absolutely gorgeous image has recently been taken of galaxy NGC 4921, which is within the Coma Galaxy Cluster(Abell 1656) in the constellation Coma Berenices. The Advanced Camera for Surveys, aboard the Hubble Space Telescope, captured approximately 80 images (50 yellow-filter shots and 30 near-IR filter shots at exposure times of seventeen and ten hours respectively) which were then stitched together to create the new image. The Coma Galaxy Cluster, of which there are about 1000 members, is about 320 million light-years away. Most of the bright galaxies were discovered by William Herschel in the late 18th century. In galaxy rich clusters such as this, numerous galaxy mergers take place that result in spiral galaxies turning into elliptical galaxies, and there is a general lack of star formation as well. NGC 4921 is a special galaxy, known as an anaemic spiral, because the star formation activity which would otherwise be vigorous enough to create the bright spiral arms is much less intense, so the arms are less prominent.

NGC 4921-Hubble/NASA

Keep your eyes to the sky and enjoy the view! ~Lisa C.

Report a Typo