H. Bond / STScI / NASA / ESA |
The Hubble Space Telescope snapped these pictures of the novalike star known as V838 Monocerotis in November 2005 (left) and September 2006 (right). The images show how a "light echo" is reverberating in the dust surrounding the star. |
The photo shows the "light echo" set off by a mysterious explosion at a variable, novalike star known as V838 Monoceros, 20,000 light-years from Earth. The light from the blast itself reached Earth back in 2002, but some of the light has been reflected off the layers of dust surrounding the star. As explained in Thursday's image advisory from the Space Telescope Science Institute, that light is spreading through the dust and reverberating, just as the echo of an Alpine yodel reverberates off the surfaces of the surrounding mountains.
Hubble has been tracking the echo for four years now, and you can watch a very cool time-lapse video of the spreading glow. (We did up our own video last year.) The latest snapshot, taken by Hubble's Advanced Camera for Surveys in September, reveals delicate details in the whorls and eddies of illuminated interstellar dust. Those patterns may be created by magnetic fields around the star, according to Hubble's scientists.
The images captured over the past four years highlight thin slices of V838 Monoceros' surroundings, with Hubble serving as a kind of cosmic CT scanner Scientists still don't know exactly what caused the 2002 outburst, during which the star flared to 600,000 times the brightness of our sun. But every year they're learning more about the blast's aftereffects.
The big question now, as it was in 2004 and 2005, has to do with how long Hubble will be able to continue watching V838 Monoceros and other celestial targets.
Ever since the 2003 Columbia tragedy, NASA has been agonizing over whether or not to send a space shuttle to Hubble for a final servicing mission. Without the servicing, Hubble may have no more than a year or two before its power system or its guidance system gives out. With the servicing, Hubble could be rejuvenated and outfitted with a nifty set of new observing instruments.
But NASA wants to make sure the shuttle and its crew will be safe, even without the haven of the international space station. Managers met today in Washington to debate whether or not they should give the go-ahead for a Hubble shuttle mission in early 2008. As we reported back in June, the space agency is already moving ahead on long-range planning for such a mission, and the official yea-or-nay decision is due to be announced to NASA employees from Goddard Space Flight Center in Maryland at 10 a.m. ET Tuesday.
If the decision is "yea," NASA will immediately provide further details on the repair plan, including the identity of the mission's crew members.
This could be one of the space program's most momentous shuttle flights ever - and considering how well the past two flights have gone, it seems hard to believe that the decision will be "nay." The advance reports from other quarters sound promising.
As luck would have it, I'm in Baltimore for the annual meeting of the National Association of Science Writers' annual meeting and the Council for the Advancement of Science Writing's New Horizons in Science symposium. So I should have a good seat for Tuesday's events at nearby Goddard. Stay tuned ... and if you want to weigh in on the risk vs. benefit of sending a crew to Hubble, feel free to leave a comment below.
Update for 5:30 a.m. PT Oct. 28:NASASpaceflight.com reports that the signs look good for a Hubble servicing mission, although that's not yet the official word. The report identifies Scott Altman as mission commander, with Ken Ham as pilot. John Grunsfeld (veteran "Hubble-hugger"), Mike Massimino and Megan McArthur are cited as prospective crew members. A backup shuttle would be prepared for launch on a dramatic rescue mission if the first shuttle suffered Columbia-style damage. The mission plan would also reportedly call for the installation of a passive docking system - to allow for an autonomous linkup for deorbiting or yet another servicing mission.
