June 27, 2011 - Satellite Power is a SNAP

Published in cooperation with The Planetary Society

Spend the year in space, one week at a time

Recent Weeks

May 14, 2012 - Monkey Nebula

May 7, 2012 - Getting a Grip on INTELSAT

April 30, 2012 - Dust in the Wind

April 23, 2012 - Celebrate Astronomy Day

April 16, 2012 - Rover Rides Again

April 9, 2012 - Mercury’s Marvelous Morphology

April 2, 2012 - A Matter of Truss

March 26, 2012 - Hubble Bubble

March 19, 2012 - Rocket Pioneer Centennial

March 12, 2012 - Southern Lights on Saturn

March 5, 2012 - A New Star in Town

February 27, 2012 - Hubble Upgrade

February 20, 2012 - Sideways Supernova

February 13, 2012 - Auroras Gone Wild

February 6, 2012 - Hubble Telescope Tune-Up

January 30, 2012 - Lunar Orbiter Liftoff

January 23, 2012 - Magellan Turns up the Stereo

January 16, 2012 - Southern Sibling Sees Stars

January 9, 2012 - Hitching a Ride Home

January 2, 2012 - Transforming the Space Frontier

December 26, 2011 - These Laws Can't Be Broken

December 19, 2011 - Long and Winding Road

December 12, 2011 - Blast from the Past

December 5, 2011 - It’s Just Like Folding a Map

November 28, 2011 - A Warmer, Wetter Mars

November 21, 2011 - Spy in the Sky

Customer Comment

Had I known about this calendar previously, I would have had previous copies!

--Richard E., Colorado Springs, CO

Read more comments

2012 Desk Calendar

FREE U.S. Shipping
SAVE 25% to 45%
Money-back guarantee

144 full-color pages
6" x 9", spiral bound
Art-quality paper

Weekly photo essay
Daily Moon phases
Night sky events
Space trivia
Holidays
Room for notes/appts

FREE Weekly E-Mail

Customer Comment

I gave it to my husband last year and he kindly requested I get him another one for this year. He really enjoys the photos on a daily basis.

--Libby V, Woodside, CA

Read more comments

The Week in Space

June 27 - July 3, 2011

Satellite Power is a SNAP In the 1950s, many people believed that nuclear generators would one day power our cities, heat our homes, and eliminate our dependence on coal and oil. These predictions did not pan out on the scale originally envisioned, but one area where nuclear power did excel is in providing power for spacecraft. The first satellite to carry a nuclear power source was the Navy’s Transit 4A satellite, which was launched fifty years ago this week. Its Space Nuclear Auxiliary Power (SNAP) 3B generator provided 2.7 watts of power. Since then, nuclear power has been a mainstay for many spacecraft, especially those too far from the Sun to rely on solar power. The Cassini spacecraft, which took this image, is powered by three nuclear generators, each 100 times more powerful than SNAP 3B.

Image credit: NASA / JPL / Space Science Institute