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Notice May 2009: Sharpless Catalog for Windows coming later this year

This Web site will display the Sharpless Catalog using CCD Imaging technology in a number of ways.

Black and White * Black and White Inverted * Hydrogen-Alpha Color * Narrowband Color

The text description is written for each object in a way that explains how the object responds to the CCD Camera and telescope I was using and what to expect when using narrowband filters such as Hydrogen-Alpha. I try to give suggestions that might work out well with larger or smaller telescopes. The science of each of the Sharpless objects comes from the Galaxy Map Web site, and each image has a link to that site if you want more information.

Galaxy Map 
This website presents a face-on map of much of the Milky Way, including the distances and positions of more than 8 thousand bright stars, star clusters, nebulae and giant molecular clouds. The location of each object on the galaxy map is based on the scientific literature.

The SuperCOSMOS Explorer by Kevin Jardine of GalaxyMap
He has added the SuperCOSMOS explorer to the Introduction to the Milky Way Explorer. This shows hydrogen-alpha images of the southern galactic plane (30° > l > 210°). As he explains in the Introduction to the Milky Way Explorer, the SuperCOSMOS data is not calibrated and there are some obvious plate transitions. Nevertheless, he thinks that these images are very useful and show details of some large faint nebulae that he has never seen before. More information: http://galaxymap.org/drupal/node/127

The Sharpless Observering Catalog by Reiner Vogel, Freiburg, Germany

Images can be used in books, magazines, or any other published paper that deals with astronomy.  However, please send me an e-mail and give me the credit as listed below:
Image by Dean Salman - http://www.sharplesscatalog.com

You can also join in at the
Yahoo Sharpless Catalog Imagers Group

Cherry Mountain Observatory
(some images were taken here)
CCD Commander
Stewart Sharpless of the U.S. Naval Observatory published his catalog of 313 HII regions and the catalog is comprehensive north of declination -27 degrees using the Palomar Sky Survey plates in 1959. (south of declination -27, the coverage is only partial)

An H II region is a cloud of glowing gas and plasma, sometimes several hundred light-years across, in which star formation is taking place. Young, hot, blue stars which have formed from the gas emit copious amounts of ultraviolet light, ionizing the nebula surrounding them. H II regions may give birth to thousands of stars over a period of several million years.

In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster such as the Pleiades. H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II by astronomers (H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). H II regions can be seen out to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies.

Many famous objects are imaged by amateur astronomers who are unaware that they are part of the Sharpless (SH2) catalog. The great Orion nebula, also known as Sh2-281, and the commonly imaged Flame nebula, known as SH2-277, are some of the December favorites. Six months later in the month of June, SH2-25, which is also known as The Lagoon nebula and the North American Nebula listed in the catalog as SH2-117, are in the sky.

Some of the objects that Sharpless includes are not HII nebulae at all; instead they are reflected star light off a galactic dust cloud above and below our own galaxy. This is known as Integrated Flux Nebulae which Steve Mandel (www.galaxyimages.com) is cataloging in his Unexplored Nebulae Project. There are a few Sharpless catalog numbers that fall into this, the largest labeled Sh2-178 near the North Star Polaris. 

To use this web site, just click on gallery button above. That will load the page with all the objects I have in the library. I plan on including the entire catalog. There is also a MORE images button you will see that displays additional images if any. I have also included on the web site free screen savers of the best Sharpless objects I have collected.

All images taken by Dean Salman


To send me e-mail, fill out the form below:


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