Picture of the Day - August 29, 2009

Sunrise on Mare Crisium

Photo and narrative by Rick Ulrich.   The sun is coming up over Mare Crisium in the upper half of this image of the eastern edge of the 3 day old Moon. The ancients wondered what caused this 350 mile almost perfectly flat plain and sometimes thought they were lakes, giving them the Latin name for seas, "mare". When telescopes were invented at the start of the 1600's, they had their answer. Mare Crisium is a huge catch-basin for molten lava, which repeatedly flowed in from the west, paving the area with flat solid rock. Proof can be seen in under low-angle illumination, which makes visible three very low "wrinkle-ridges" where the liquid lava lapped up over older solid lava before solidifying. Mare Crisium is also a traditional test for 20/20 vision, if you can see it as a tiny detached dark area in the upper-right of the full Moon. This image was captured through a 4" refractor telescope at f/9 (900 mm) into a Canon EOS 50D for 1/15 second, ISO 100. Although a quarter-million miles away, features the size of shopping-mall parking lots are discernible. --Rick Ulrich     Visitor Comments... Name: Rick Rouse Town: Abingdon, VA Outstanding job Mr. Ulrich! And thanks so much for the detailed information about Mare Crisium - very interesting indeed.     Name: Ed Morrison Town: Dunwoody, GA I have often peered at Mare Crisium and wondered the same thing the ancients did. Now I know. Thanks!     Name: Claire Helms Town: Greenville, SC Magnificent work here Mr. Ulrich. I can still remember the awe I felt when I first peered at the moon through the large telescope in my university's observatory. Sir, you have inspired me to purchase a telescope of my own and have a go at capturing some lunar images with my Nikon D300.     Name: Gordon Brugman Town: Gatlinburg, TN Wonderful image, Mr. Ulrich. Proof that there is no place where light can travel where a great photograph can’t be taken. And if we can’t go to the subject, capturing the light that travels through space can bring the subject to us! Thanks for an inspirational image.     Name: Mark Devers Town: Promontory, UT Awesome!!!   Comment on today's picture  |  View previous "Pictures Of The Day"  |  Submit a photo Why I publish the "Picture Of The Day"