Looking Up: The cat's paw nebula is home to old, new and upcoming stars
Astrophotographer Ted Wolfe has successfully moved his telescope from Naples to the Atacama Desert in northern Chile. The entire set-up is now operated from here in the U.S., but the scope itself is in Chile. His pictures of colliding galaxies, dying stars, supernovas, glowing nebulas, etc., are published in the leading national magazines in the field of astronomy. Exhibits of his pictures have appeared in numerous science museums, universities and institutions -- including a 20-month show featuring a large number of his images at the Kennedy Space Center. A full collection of his pictures are on permanent display at the Center for Space Studies at the University of Florida.
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Halloween was celebrated last month but the witch's cat left its paw print in space. Here we have a good picture of it, and astronomers actually do refer to it as the "Cat's Paw."
Its official name is NGC 6334, and it can be found in the constellation Scorpius at the tip of the scorpion's tail. (Perhaps the cat had a go at it.)
This rather bizarre object was discovered by the astronomer John Herschel back in 1837 as he peered up at the southern night skies from the Cape of Good Hope in South Africa. This is a very faint object to see in a telescope, and his notes don't describe much being there. However, with today's modern telescopes and specialized astronomical cameras (CCDs), the paw print comes to life in considerable detail.
NGC 6334 lies about 5,500 light years away. When you consider that our galaxy stretches about 100,000 light years across, this puts it pretty close to our spot in the galaxy. It is, in fact, one of the closest HII-emission nebulas to the earth. So it is a popular site with professional astronomers specializing in the study of newborn stars.
This is a vast star-forming region, measuring almost 100 light years across. Tens of thousands of stars have been born in the Cat's Paw in the last few million years. Many are great luminous giants that are 10 times the size of our own star, the sun. Most of these brilliant blue stars are hidden in the dust of the red nebula material seen here.
Among the new stars astronomers have found, about 2,000 are still surrounded by their proto-planetary disks. Out of the gas and dust in these disks, planets will form, creating brand new solar systems. Moons circling the planets will appear, and comets will begin to streak across the newly minted systems.
The red color of the Cat's Paw signals that this is an HII-0emission nebula, a virtual nursery for baby stars. The red glow is coming from the ionized hydrogen in the Cat's Paw, a sure sign that star formation is going on.
When clouds of gas and dust in space cool to very low temperatures some of the material condenses down to form stars. The temperature in the Cat's Paw dust has been measured at -445 degrees Fahrenheit. So its got everything to make stars.
However, it's far from finished. Astronomers estimate that the remaining gas and dust holds enough material to create another 200,000 stars. Right now the Cat's Paw is undergoing a period of unusually rapid star formation. This particular cycle started relatively recently and will probably last a few million years more.
During this period the look of the nebula will change. The current "Cat's Paw" appearance is really transitory.
Right now great, red "puffs" (or "paws" if you like) of gas and dust dominate the landscape. However, as more of the gas and dust is blown away by the stellar winds of the newborn stars, future astronomers will see more of a mixed picture of brilliant star clusters laced with smaller remnants of gas and dust.
The Cat's Paw will then look like a group of Pleiades star clusters. Although not as bright, since the Pleiades are 10 times closer to us.
So enjoy the Cat's Paw, and understand, that like cats everywhere, their appearance comes and goes.
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Ted is a member of the Everglades Astronomical Society. Organized in 1981 it serves the Naples community, providing information in all aspects of amateur astronomy. Its goals include educating the general public, school children and other groups to the wonders of the universe. The society meets at 7 p.m. every second Tuesday of the month at the Norris Center (public invited). Regular viewing visits to a special, dark sky site in the Everglades are held each month, allowing the general public to observe the night sky through telescopes, under pristine conditions. For more information, visit the website at http://naples.net/clubs/eas. A Blu-ray disc for viewing on TV is now available which features 70 of Ted's deep space images with original background music. For more information, go to www.naples.net/clubs/eas/sales.html.