June 23 2010 Astronomy Newsletter
Here's the latest article from the Astronomy site at BellaOnline.com.
Cygnus the Swan
Seduction and supergiants, blue and amber stars, vast explosions, a giant cloud that looks like North America. Where does myth end and astronomy begin? Here is a quick tour of some of the highlights of the constellation Cygnus the swan.
If you missed my greetings on the Astronomy Forum, a slightly belated Happy Solstice. I've tried not to exclude the southern hemisphere by specifying the Summer Solstice. Do I have any readers from south of the Equator?
There was also an extra article for the occasion.
Why planets have seasons
For people living outside the tropics, June 21st is the longest or shortest day of the year, a solstice. It marks the first day of summer in the northern hemisphere and winter in the southern hemisphere. But why do we have seasons? And do other planets have them?
Yesterday was the 335th anniversary of the commissioning of the Royal Greenwich Anniversary by Charles II (June 22, 1675). He wasn't a keen astronomer like George III, but if England were to remain a maritime power, astronomy was essential, especially to address the problem of determining longitude.
The Prime Meridian goes through Greenwich and it's also the site of the National Maritime Museum.
And Happy Birthday to Charles Messier(06.26.1730-04.12.1817). He'll be 280 on Saturday -- but not able to celebrate. Messier was the great 18th century French comet hunter. Comets look a bit like fuzzy blobs unless they're very bright, near the sun, etc. But with the telescopes of the time, there were a number of fixed objects that also looked like fuzzy blobs. Messier cataloged them so that they'd not confuse comet hunters.
I wonder what he would think if he could know that his enduring fame is based on the catalog of things-that-aren't-comets.
Please visit astronomy.bellaonline.com for even more great content about Astronomy.
To participate in online discussions, this site has a community forum all about Astronomy located here -
I hope to hear from you sometime soon, either in the forum or in response to this email message. I welcome your feedback!
Do pass this message along to family and friends who might also be interested. Remember it's free and without obligation.
Mona Evans, Astronomy Editor
One of hundreds of sites at BellaOnline.com
Unsubscribe from the Astronomy Newsletter
Online Newsletter Archive for Astronomy Site
Master List of BellaOnline Newsletters