Full Moon Fun Plus Astronomers Discover New Solar System

The nearly full moon shines from inside a corner of Duluth's iconic Aerial Lift Bridge last night about 20 minutes after sunset. 300mm lens at f/5.6, ISO 400, 1/60 second exposure. Photo: Bob King

Partly cloudy skies made for an interesting moonlit walk last night. I noticed that when the moon disappeared into clouds and then returned, the effect was more dramatic than when the sun does the same. Maybe it’s just me, but there’s a slight feeling of dread when the moon vanishes behind clouds. The light goes out, night suddenly grows deeper, and a bit of one’s inner cheer drains away. Briefly. The moon returned as it always does and lit the pines and spruce brightly enough to see their dark greens.

The Full Moon will light the night tonight. If you want to watch or take pictures, click on the link on the right side column of my home page for moonrise times for your city. In Duluth, the moon comes up at 7:43 p.m. and should make a striking sight above the blue waters of Lake Superior around 8 p.m.  Taking pictures of the moon during early twilight is easy because its brightness neatly matches that of the sky. Find an interesting foreground scene and then just point and shoot! If you use your camera’s wide angle lens setting, the moon will appear very small in the frame. Try to find a scene where you can zoom in – to make the moon bigger – while at the same time including something clearly recognizeable in the foreground.

About the time the moon starts to look bright and shiny to your eyes, the wide difference in exposure times between it and the darker foreground can cause problems. Exposing for the scene will give you a too-bright, overexposed moon while exposing for the moon will make for a dark foreground scene. Catch it at the right time and your picture will look very close to what your eye saw. Anytime during the half-hour after sunset should work.

The moon joins the brightest stars in the south and Jupiter in the east tonight. This map shows the sky around 10:30 local time. Created with Stellarium

As twilight deepens to night and the moon takes a commanding position in the southeastern sky, take another look. You’ll see that it’s part of a very large kite-shaped asterism that includes Jupiter, off to the left, and Altair, Vega and Deneb higher up.

The European Southern Observatory (ESO) announced today that astronomers using the 3.6-meter (142-inch) telescope at LaSilla, Chile, and an advanced spectrograph, detected a new system of extrasolar planets around sun-like star HD 10180, located 127 light years away in the southern constellation of Hydrus the Lesser Water Snake. At least five planets, each about the size of Neptune, have been found orbiting the star at very close distances ranging from 5.6 to 130 million miles. For comparison, the Earth is 93 million miles from the sun. The five planets, their orbits and sizes were deduced after six years of studying the tiny and complex gravitational tugs they exert on their host star.

Artist's impression of the planetary system around the Sun-like star HD 10180. Credit: ESO

The data also seem to point to the existence of two more planets for a total of seven in all, nearly as many as our own solar system. One of them may be the smallest exoplanet yet detected with a mass only 1.4 times greater than Earth and orbiting a mere 1.9 million miles from its sun.

The Holy Grail in extrasolar planet detection is finding Earth-sized bodies at the right distance from their central stars where, as the Goldilocks story says, the porridge is neither too hot nor too cold but just right . While this possible new planet is similar in size to our own, its proximity to its host star would probably cook life’s goose. No matter. We’ll keep hunting – that’s something we humans do well.