Space

June 3, 2013

NASA’s Swift produces best ultraviolet maps of nearest galaxies

New surveys conducted by NASA’s Swift provide the most detailed overviews ever captured in ultraviolet light of the Large and Small Magellanic Clouds, the two closest major galaxies to our own. Swift team member Stefan Immler, who proposed the imaging project, narrates this quick tour. All visible light imagery provided by Axel Mellinger, Central Michigan University

http://www.youtube.com/watch?v=53yokIKAnDs&feature=youtu.be

Astronomers at NASA and Pennsylvania State University have used NASA’s Swift satellite to create the most detailed ultraviolet light surveys ever of the Large and Small Magellanic Clouds, the two closest major galaxies.

“We took thousands of images and assembled them into seamless portraits of the main body of each galaxy, resulting in the highest-resolution surveys of the Magellanic Clouds at ultraviolet wavelengths,” said Stefan Immler, who proposed the program and led NASA’s contribution from the agency’s Goddard Space Flight Center in Greenbelt, Md.

Immler presented a 160-megapixel mosaic image of the Large Magellanic Cloud and a 57-megapixel mosaic image of the Small Magellanic Cloud at the 222nd American Astronomical Society meeting in Indianapolis June 3.

The new images reveal about 1 million ultraviolet sources in the LMC and about 250,000 in the SMC. The images include light ranging from 1,600 to 3,300 angstroms, which is a range of UV wavelengths largely blocked by Earth’s atmosphere.

“Prior to these images, there were relatively few UV observations of these galaxies, and none at high resolution across such wide areas, so this project fills in a major missing piece of the scientific puzzle,” said Michael Siegel, lead scientist for Swift’s Ultraviolet/Optical Telescope at the Swift Mission Operations Center at the university in State College, Penn.

The LMC and SMC lie about 163,000 light-years and 200,000 light-years away, respectively, and orbit each other as well as our own Milky Way galaxy. The LMC is about one-tenth the size of the Milky Way and contains only 1 percent of the Milky Way’s mass. The SMC is half the size of the LMC and contains about two-thirds of its mass.

Despite their modest sizes, the galaxies loom large in the sky because they are so close to us. Both extend far beyond the UVOT’s field of view, which meant thousands of images were needed in order to cover both galaxies in three ultraviolet colors centered at wavelengths of 1,928 angstroms, 2,246 angstroms, and 2,600 angstroms.

Viewing in the ultraviolet allows astronomers to suppress the light of normal stars like the sun, which are not very bright at such higher energies, and provides a clearer picture of the hottest stars and star-formation regions. No telescope other than UVOT can produce such high-resolution wide-field multicolor surveys in the ultraviolet. Swift’s wide-field imaging capabilities provide a powerful complement to the deeper, but much narrower-field imaging power of NASA’s Hubble Space Telescope.

To produce the 160-megapixel LMC mosaic, Swift’s UVOT acquired 2,200 snapshots for a cumulative exposure of 5.4 days. The 57-megapixel SMC image comprises 656 individual images with a total exposure of 1.8 days.

Both images have an angular resolution of 2.5 arcseconds, which is a measure of their sharpness. Sources separated by this angle, which is equivalent to the size of a dime seen from 1 mile away, are visible as distinct objects.

“With these mosaics, we can study how stars are born and evolve across each galaxy in a single view, something that’s very difficult to accomplish for our own galaxy because of our location inside it,” Immler said.

The Large and Small Magellanic Clouds are readily visible from the Southern Hemisphere as faint, glowing patches in the night sky. The galaxies are named after Ferdinand Magellan, the Portuguese explorer who in 1519 led an expedition to sail around the world. He and his crew were among the first Europeans to sight the objects.

Pennsylvania State University manages the Swift Mission Operations Center, which controls Swift’s science and flight operations. Goddard manages Swift, which was launched in November 2004. The satellite is operated in collaboration with Penn State, the Los Alamos National Laboratory in New Mexico and Orbital Sciences Corp. in Dulles, Va. International collaborators are in the United Kingdom and Italy, and the mission includes contributions from Germany and Japan.




All of this week's top headlines to your email every Friday.


 
 

 

Headlines September 29, 2014

News: U.S. military limits warplanes used for Islamic State bombingsĀ - The U.S. is relying mostly on warplanes already positioned in the region for its air war against the Islamic State, as opposed to dispatching a major buildup of aerial forces that happened in previous campaigns.   Business: At DOD, it’s use-it-or-lose-it seasonĀ - As fiscal 2014...
 
 

News Briefs September 29, 2014

Navy awards ship design grant to UNO The University of New Orleans has received a $210,000 grant from the Navy s Office of Naval Research to test information gathering and analysis techniques intended to improve warship design. The goal for warship designers is to produce a vessel that can be repurposed numerous times throughout its...
 
 
Courtesy photograph

TACP-M ties it all together

Air National Guard photograph by SSgt. Lealan Buehrer Tactical air control party specialists with the 169th Air Support Operations Squadron survey an enemy-controlled landing zone before calling in close-air support Aug. 14, 20...
 

 
Air Force photograph by A1C Thomas Spangler

Nellis aggressor squadron inactivated

Air Force photograph by A1C Thomas Spangler SSgt. Justin White signals to Maj. Sam Joplin to begin taxiing a 65th Aggressor Squadron F-15 Eagle to the runway Sept. 18, 2014, at Nellis Air Force Base Nev. The roles and responsib...
 
 
Army photograph by SSgt. Mary S. Katzenberger

82nd Airborne helps commemorate 70th Anniversary of Operation Market Garden

Army photograph by SSgt. Mary S. Katzenberger A paratrooper assigned to the 82nd Airborne Division, reflects near the grave of a British paratrooper at the Arnhem Oosterbeek War Cemetery, Sept. 14, 2014, in the Netherlands. The...
 
 

Raytheon awarded $251 million Tomahawk missile contract

The U.S. Navy has awarded Raytheon a $251 million contract to procure Tomahawk Block IV tactical cruise missiles for fiscal year 2014 with an option for 2015. The contract calls for Raytheon to build and deliver Tomahawk Block IV cruise missiles to the U.S. Navy and U.K. Royal Navy. Raytheon will also conduct flight tests...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>