Monday, October 10, 2011

Enceladus as you've never seen it!


Saturn's moon Enceladus has captured the imagination of scientists over the last several years because of the active jets near its south pole. Enceladus is spewing material into outer space as it orbits Saturn, creating the "E" ring, and spurring speculation about the conditions in its subsurface oceans. This photo, captured by the spacecraft Cassini last year, shows a new view of these geysers (the south pole here is shown in the "up" position). As with all photos taken of the active geysers, the sun is backlighting the moon, making the plumes visible. The surface of Enceladus itself is illuminated by "Saturn-glow," reflected sunlight from Saturn, bouncing and lighting the night side of Enceladus.

Read more about this spectacular image at the Planetary Society Blog.

Tuesday, June 7, 2011

Summer Events in Astronomy and Space Exploration

Since the planetarium is closed during the summer, we won't be around to point you to special events through our Facebook and Twitter updates. So, we thought it would be good to give you a heads-up regarding some of the exciting events you'll want to watch for over the summer.
  • SUMMER Solstice:  The official beginning of summer (northern hemisphere) is on June 21st.
  • FINAL Space Shuttle Launch:  The last shuttle, Atlantis, sits on the launch pad as I write this. The lift-off is currently targeted for July 8th. With it's crew of four, Atlantis will ferry spare parts and supplies to the International Space Station.
  • DAWN arrives at the asteroid Vesta:  After a four year journey, the Dawn spacecraft is creeping up on the second largest asteroid, Vesta. It's currently slated to arrive at Vesta in July.
  • JUNO heads toward Jupiter [alternate site]:  With the launch window for Juno opening on August 5, the spacecraft will begin a journey which will help us to know Jupiter and the Solar System like never before. I highly recommend the online tour at the primary link above.
  • PERSEID Meteor Shower:  Unfortunately, the full moon will brighten the sky, obscuring many of the meteors at the peak, August 12-13. But the Perseids are somewhat active throughout August.
Have a great summer! And we look forward to seeing you at our public events/shows in the fall, and working with your groups in the planetarium.

Wednesday, April 27, 2011

Spectacular Saturn!

Tonight's public planetarium program is all about the beautiful planet Saturn. If you'd like to learn more about Saturn, consider exploring NASA's Cassini web site. Or you may want to make your own scale diagram of the Saturn system!
Scale Diagram of Saturn with Questions (1 MB PDF file)

Enjoy!

Thursday, January 27, 2011

Astrology and a 13th Zodiac Constellation? New News?

We've received several questions about some of the news stories lately related to astrology. The TV news story I saw briefly mentioned that there are actually 13 constellations that the Sun seems to pass through instead of the 12 listed by astrologers, and that the dates for when the Sun appears in those constellations doesn't match with the dates the astrologers use. Honestly, our first reaction was to say "what stirred up this news item now"? To us in astronomy, this is OLD news. We can't find the original article, but it apparently ran in the Star Tribune in Minneapolis. And the story has gone viral over the Internet.

First, to clarify, astrology is the belief that the positions of celestial bodies has some influence on human affairs. Astronomy is the scientific study of celestial objects and phenomena. People often get those words mixed up.

There are lots of cool astronomy concepts to explore related to the zodiac constellations, so we've decided to focus our February 16th public planetarium programs on this subject. The programs are entitled "What's Your Sign -- Really?", and we hope you can join us. But until then, I thought I'd provide a couple of links to good sources of information related to the subject.


  • A Sign of the Times:  Sky and Telescope ran a nice article, which included an essay printed in their magazine in 1998.
  • An Astronomer Looks at Astrology:  (PDF file) the Astronomical Society of the Pacific provided an article which shows how to debunk astrology.
The focus of our public planetarium programs will mostly be about the Earth's motions. We'll explore how it could be that the Sun would appear to be "in" a constellation, and how that would change throughout the year. And we'll show how the Sun's position among the stars has changed over the past 2,000 years. It will be a lot of fun.

Feel free to post comments and questions if you are still struggling with a certain issue or concept.

Tuesday, January 25, 2011

The Milky Way Galaxy

Our public planetarium programs on January 19th were entitled "Galaxies!" Among the many interesting topics we tackled, we had a lot of fun exploring our place in the Milky Way Galaxy. As a follow-up to the program, we wanted to share a couple of links with you, and share a new, related, citizen science project that has emerged since the programs last week.

In the programs, we showed Axel Mellinger's fantastic mosaic of the sky as seen from all sides of the Earth (image inserted on the left). It beautifully displays our view of the Milky Way Galaxy as we see it from the inside. We encourage you to explore this image at its full resolution, and learn about how he made the image at his Milky Way Panorama 2.0 site.

Today, astronomy enthusiasts have some wonderful ways to actually help with many areas of astronomy research! Check out the Zooniverse web site to search for planets, identify craters on the moon, and so much more! The project we highlighted in the planetarium programs this month was the Galaxy Zoo.

If you are interested in actually helping to explore our Milky Way Galaxy, you're in luck! In December they started another research area using Spitzer Space Telescope images called The Milky Way Project. Anyone can help! Explore cool images, draw the bubbles that you see in the photo, and help contribute to science! How cool is that!

[adding another resource: 6/8/11]
Similar to the Mellinger mosaic of the sky, the new Photopic Sky Survey has some incredible differences. It's a beautiful 5,000 mega-pixel image! Zoom in and out, scan around, and be sure to click the "i" button to add the labels. Enjoy!