Welcome to Winter

Image by Matt Gibson on flickr

– Yesterday Earth arrived at a point in its orbit around the sun where the north end of the planet has its greatest tilt away from the sun even though we’re closer now than any other time of year. Why was it so warm into late fall? Lag time of heat loss from the planet’s surface: objects have what’s called thermal mass – the ability of a material to store heat; a material’s resistance to change in temperature as heat is added or removed. Water has a relatively high thermal mass.

– Three extraordinary new discoveries announced by NASA Curiosity at Mars researchers at AGU last week:

1. Organic compounds thought to have originated at Mars found in tested rock samples (earlier detection of organics turned out to include carbon from earth in the test equipment) – not proof of past life or current life but probable confirmation that organic molecules existed on Mars;
2. Spike in atmospheric methane near Curiosity rover from late ’13 into early ’14 indicates some currently active mechanism for releasing methane – either the Rover farted or there are cows on Mars;
3. Ratio of hydrogen to deuterium in tested rock sample gives clues abt when Mars may have lost its surface water.

– December 24 Christmas Eve – 2.5 day old moon sits just west of Mars. Sharp-eyed observers can spot bright Venus VERY low in the WSW in a 15-minute window from 5-5:15p.

– Apollo 8 astronauts Borman, Lovell and Anders are on their way to the moon as the first humans to leave earth orbit. Enter lunar orbit Xmas Eve, return to Earth Dec. 27.