Here's the latest article from the Astronomy site at BellaOnline.com.
ABC of Astronomy – G is for Gravitational Lens
We have optical lenses in telescopes, cameras and our eyes. They're made of transparent material, and they focus light. However astronomers now make use of gravitational lenses to detect distant galaxies, dark matter and extrasolar planets. What's a gravitational lens made of, and how does it work? http://www.bellaonline.com/articles/art302146.asp
For six months, each day has been shorter than the last, the Sun lower in the sky. Will it disappear altogether and leave the people bereft in the dark cold winter? The winter solstice is the shortest day of the year and is associated with more festivals than any other astronomical event.
With the winter holidays coming up (in the northern hemisphere), it seemed a good time to remind us of the winter celebration that predates all the others, i.e., the winter solstice.
I see that Hanukkah begins at Sunset on Sunday 6th. My warm greetings to those who will be celebrating it. Happy Hanukkah to you and your friends and families.
Today is the day for opening the first window on the advent calendar. I've tried to find an online space/astronomy advent calendar, but although I've seen them in previous years, no luck this time. If anyone knows of one, if you let me know, I'll pass it on.
*Hubble holiday cards*
There is the usual splendid selection of holiday e-cards on the Hubble Site: http://hubblesite.org/gallery/holiday/ There are instructions for downloading them for printing in various sizes. I don't have a printer (and am too disorganized to mail them on time), so email them with my greetings.
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I hope to hear from you sometime soon, either in the forum http://forums.bellaonline.com/ubbthreads.php/forums/323/1/Astronomy 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.
I wish you clear skies.
Mona Evans, Astronomy Editor
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