Telescopes do a triple take
Posted: Wednesday, February 11, 2009 9:51 AM by Alan Boyle
NASA / ESA / CXC / SSC / STScI
The spiral galaxy Messier 101 is shown in multiple wavelengths from the Spitzer
Space Telescope (red for infrared), the Hubble Space Telescope (yellow for visible
light) and the Chandra X-ray Observatory (blue for X-rays). Click on the image for
a larger version from the Space Telescope Science Institute.
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If anyone doubts that three telescopes are better than one, the latest image from NASA's Great Observatories should change that view with a single glance.
Poster-size prints of the dazzling Pinwheel Galaxy - as seen by the Hubble, Spitzer and Chandra space telescopes - are being distributed to more than 100 starstruck locales to celebrate Galileo Galilei's birthday on Feb. 15 as well as the 400th birthday of his telescope.
The Pinwheel Galaxy, also known as Messier 101, has been photographed many times before: This HD image is a prime example. The new version, however, combines multiple wavelengths to produce a view that can't possibly be seen by any single telescope. "It's like using your eyes, night vision goggles and X-ray vision all at the same time," Hashima Hasan, lead scientist for the International Year of Astronomy at NASA Headquarters, said in Tuesday's image advisory.
The picture shows how different telescopes work together to give scientists an all-around look at cosmic objects:
- Hubble's visible-light view is shown in yellow, highlighting the galaxy's swirls of bright stars and glowing gas.
- Spitzer's infrared perspective is shown in red. The telescope's camera is tailor-made to spot the glow given off by lanes of dust where clouds collapse to form new stars.
- Chandra's X-ray vision is shown in blue. These highlight the galaxy's most energetic emissions, from supernova remnants and the whipped-up surroundings of black holes.
The composite view appears along with the individual perspectives on wall-size prints that are being distributed to 76 museums and 40 schools and universities in 39 states this month, starting on the day before Galileo's birthday. Check out the image advisory to find out which institution near you is participating in the "International Year of Astronomy Great Observatories Image Unveiling."
This year has been designated the International Year of Astronomy to mark the 400th anniversary of Galileo's telescope, which opened a new window on the universe. The IYA has been under way for more than a month now, but the best is yet to come. Astronomers are planning a constellation of events during the "100 Hours of Astronomy" in April, including the unveiling of a "people's choice" Hubble image. (Have you voted yet? The interacting galaxies known collectively as Arp 274 are currently in the lead, with more than 80,000 online ballots cast so far.)
I'm still waiting to find out how to get a Galileoscope, a low-cost telescope kit that will be distributed to thousands of stargazers as an IYA project. The 20-inch-long scope is more capable than Galileo's instrument and should sell for around $12.50.
To learn more about the IYA celebration, check out the Web sites set up by NASA and the International Astronomical Union.
