Over the next week or so you can watch the lion diving towards the western horizon as dusk fades. Between 10:00 and 10:30 pm is about right. A few nights ago I was out watching the holiday fireworks. The neighbors put on a great show and I could see other, more distant flashes. But then things started to settle down and the sky darkened to reveal the best fireworks of all - the stars and planets.
Sky and Telescope illustration
The constellation makes its first appearance in the evening sky in late winter, rising in the east. It's a hopeful sign that another spring is on the way. Earth's orbit shifts his position up each night placing Leo high overhead in May and finally sending him westward towards an annual rendezvous with the Sun. Fall and winter will come and go before we see him in the evening again.
While most of us see a pattern that does indeed resemble a crouching lion, astronomers see much more. Regulus, the "star" of the constellation, is actually four stars gravitationally bound whose light merges as one to our eyes. There are double stars, variable stars, dwarfs and giants as well as flare stars and a carbon star or two. Algieba is known to have a planet in orbit as do a dozen other Leo stars. There are also galaxies sprinkled across the sky in Leo. Huge clans of billions of stars, they are massive but too distant to be seen by the eye alone.
Jupiter also offers much more than meets the eye. There are four large Galilean moons that can be seen with binoculars. These got their namesake astronomer in trouble with the Church when he suggested that not everything orbits around the Earth. Beyond the four biggies are dozens of smaller moons (over 60 and counting). When we look at Jupiter's colorful bands and spots we're seeing the top of its thick atmosphere. It's mostly hydrogen and helium, the same elements that make up the Sun. Indeed, you could almost call Jupiter a "failed" star because it's not quite massive enough to create the pressures and temperatures needed for fusion, the process that produces the intense heat and light which defines stellar.
Damian Peach photo from Sky and Telescope
Artist's illustration of Juno approaching Jupiter
Sky and Telescope illustration
Curiosity sees its shadow on Mars
When it starts to overwhelm I scurry back to our cozy little village solar system where you can peek out the window and watch the antics of those crazy next door neighbor planets. All in all, not a bad place to call home.
Obviously I love astronomy and star gazing so I have to tell you how lucky I am to know a real live astronomer. Dr. Adele Plunkett is a good friend of Holly's. They skied and ran together at school and Adele has been up to the farm several times to visit. Earlier this year Adele won the Robert L. Brown Outstanding Doctoral Dissertation Award for her research on how stars form in families from molecular clouds. She used the ALMA radio telescope for her work. It's located in northern Chili and is the most complex astronomical observatory ever built. I believe Adele is currently an ALMA Fellow at the European Southern Observatory.
After four years at Middlebury (2005-2009) she continued her education at Yale, eventually earning a PhD in astronomy. This involved many trips to Chili for telescope time. Amazingly, she also ran marathons, did triathlons and X-C ski raced during that time. She even allowed Holly to talk her into doing the Stowe Derby and has since forgiven my daughter!
With Adele chasing down clues I'll bet we know more about how stars form in the near future. Congratulations Adele for all your hard work and achievement and thanks for being my "real live astronomer".
Adele has two blogs you might want to check out: Adele en Chili and The Observing(b)Log
Dr. Adele Plunkett
For a fun look at Jupiter and all its little solar system siblings I'ld recommend Dava Sobel's The Planets. It's science with a light lyrical touch and lots of interesting and unexpected anecdotes.
Click here for a great shot of Jupiter, its moons and a familiar old friend.
In case of clouds
From the web