Wednesday, May 25, 2011

APOD 4.7

This is a photo of the launch of the space shuttle Endeavor, which occured May 16th, that marked this particular shuttle's last mission.  Endeavor is scheduled to travel to the International Space Station and pursue a project that will detect dark matter (matter that is theorized to exist due to the presence of gravitational effects but does not emit or absorb light or radiation that is easily seen), charged antimatter (composed like regular matter but with antiparticles) and strangelets (hypothetical particles that consist of equal numbers of up, down and strange quarks) that will last a total of 14 days.  The six crew members of this mission titled STS-134 are Commander Mark Kelly, Pilot Gregory H. Johnson and Mission Specialists Michael Fincke, Greg Chamitoff, Andrew Feustel and European Space Agency astronaut Roberto Vittori.  Endeavor marks the 36th mission to the International Space Station and is one of the last shuttle launches, the last being Atlantis which s scheduled for July. 

APOD 4.6

The image above is of the circumpolar constellation Ursa Minor or "The Little Dipper" as it is commonly known, which was listed by Ptolemy as apart of his list of 48 constellations.  The second magnitude star Polaris, which marks the north celestial pole at this time but will later shift location, is clearly visible at the center of left hand side.  Although it is not the brightest star in the night sky (it is actually the 48th brightest), it is the brightest star of its neighbors in this photo and it is the brightest Cepheid variable star. Cepheid variable stars like Polaris are important to Astronomers because a relationship exists between their absolute magnitude and pulsation period that enables us to determine their distances and therefore, the distances to other galaxies!  

Monday, May 23, 2011

David Levy Biography

David Levy was born in Montreal, Canada on May 22, 1948 and cultivated a fascination with astronomy beginning as a child.  Despite this early precociousness displayed in this particular field, Levy obtained a bachelor's and master's degree in English Literature instead.  In 1967, Levy was nearly removed from the Royal Astronomical Society of Canada's Montreal Centre after a few quarrels with the group's leaders.  However, after developing communication through letters with Isabel Williamson, one of the leaders he had infuriated the most, he became a regular visitor and Levy was able to maintain his position as a member of the centre. 

Levy has been able to discover 22 comets, nine of which were found using his own backyard telescopes.  One of his most notable accomplishments was made through his work at the Palomar Observatory, located in California, with the help of the fellow astronomers Eugene and Carolyn Shoemaker.  They were able to discover the comet Shoemaker-Levy 9, appropriately named for their two last names, that actually collided with the planet Jupiter and created one of the most dramatic and visually enticing explosions ever witnessed in our Solar System.  David formerly served as the editor from 1997 until 2006 for "Parade Magazine", which reached an audience of about one fourth the population of the United States Levy is currently a contributor to the famed "Sky and Telescope" magazine and regularly writes articles as a apart of the "Star Trails" column.  Levy has written or edited 35 books in total and has won an Emmy in 1998 as one of the writers for  the Discovery Channel's documentary "Three Minutes To Impact".  He is a frequent guest on television shows and talk shows, such as "Good Morning America" and "The Today Show". 

Also David and his wife Wendee host a radio show once a week on the website letstalkstars.com.  David Levy is president of the National Sharing The Sky Foundation, that seeks to educate the general public about Astronomy and stimulate interest to further pursue the subject.  Levy and his wife currently live in Vail, Arizona and are members of The Jarnac Comet Survey which operates mainly out of the Arizona Jarnac Observatory but has telescopes stationed internationally.  Ironically after nearly being expelled from Canada's Royal Astronomical Society early in his career, Levy has been one of the most, if not the number one, successful modern astronomers and continues to be involved in an extreme variety of projects.          

APOD 4.5


The lagoon nebula, as pictured above, is an extremely active star-forming region located in the Milky Way Galaxy and is classified as a M8 object.  This particular image was created by the Argentinian astronomers Julia Arias and Rodolfo Barbá who used the Gemini South telescope with the Gemini Multi-Object Spectrograph.  They created this final version as a composite image of various photographs taken by two narrow band filters that are sensitive to hydrogen.  The galaxy has been referred to as "psychedelic" because the photons had to travel a distance of 5,000 light years in order to appear in front of this camera, which makes it an actual flashback as the distance is so large.

David Levy Biography Sources

http://www.jarnac.org/aboutdavid.htm

Astronomy Magazine.  Columnist Biography
http://www.astronomy.com/contributor.aspx?id={E1E4148B-A5F4-4B5F-8F60-A14A06A13C96}

http://www.astronomyoutreach.net/index.php?title=David_H._Levy