All times Eastern.

• 6PM, Discovery HD - Comet Collision!: NASA launches a spacecraft designed to fly directly into a comet.
• 6PM, G4 - Ninja Warrior
• 6PM, MTV - Exposed: People choose dates based on lie-detector results.
• 6PM, History Channel - Mega Disasters: Mega Freeze: The devastating effects of a dramatic climate change.
• 6:30PM, DIY - Solar Solutions: Solar powered attic fan.
• 7PM, Food Network - Good Eats: Okraphobia. Okra.
• 7PM, Discovery Health - Impact: Stories of Survival: Martial Artist on Fire. A man snaps his neck attempting a sky diving maneuver; a martial arts expert has a mishap with fire; a figure skater suffers a severe fall.
• 7PM, Discovery HD - Africa’s Elephant Kingdom: An elephant family journey across the African plains.
• 7PM, Speed - Chop Cut Rebuild: Sparks Flying. Welding work on the vintage Ford; Dan struggles at the Camaro shop.
• 7PM, Versus - World Combat League: Oklahoma Destroyers at Dallas Dragons

8PM and on after the jump!

• 8PM, PBS (NY 13) - Nova: Bone Diggers. Unknown kangaroo species and the first complete skeleton of the largest carnivorous marsupial ever found are recovered from Australia’s Nullarbor Plain.
• 8PM, History Channel - Siberian Apocalypse: In June 1908 a giant fireball explodes in the Siberian sky with a force 1,000 times greater than the Hiroshima bomb, decimating 830 square miles of forest.
• 8PM, Discovery HD - Roush Racing: Driver X: The First Spin. The halfway point of round one.
• 8PM, G4 - X-Play: “Pirates of the Caribbean: At World’s End”; “Catan”; “Calling All Cars.”
• 8PM, Military Channel - Top Ten Infantry Fighting Vehicles: Designs are rated based upon innovation, protection, mobility and overall battlefield performance.
• 9PM, Discovery Channel - Deadliest Catch: A Frozen Finish. The end of the 2007 opilio crab season.
• 9PM, History Channel - The Universe: Jupiter: The Giant Planet. Jupiter has flowing colors and more than 60 moons.
• 9PM, Military Channel - Futureweapons: No Place to Hide. Weapons that leave the enemy with no place to hide.
• 9PM, Discovery Times - Industrial Wonders: Transcontinental Railway. The Transcontinental Railway connects the eastern United States with the promise of the West.
• 9:30PM, Sundance - Dead in the Water: The growing demand and limited supply of water.
• 10PM, Discovery Channel - After the Catch: On the Edge. Notorious pranks at sea and on shore.
• 10PM, Military Channel - Firepower: Desert Wargames. The Army conducts desert war games in California.
• 10PM, Science Channel - Space Station and Beyond: Space station experience.
• 10PM, Fuse - Rad Girls: Three crazy California girls say and do anything to shock and entertain in hilarious challenges and outrageous situations.
• 11PM, Comedy Central - Daily Show: Brian Williams, anchor of NBC “Nightly News”
• 11PM, Food Network - Good Eats: Myth Smashers. Food myths.
• 11PM, Speed - Unique Whips: SEMA & Softball. Tony Stewart’s Lambo gets new rims and heads to SEMA; softball against a rival show.
• 11PM, Discovery Times - Industrial Wonders: SS Great Eastern. The SS Great Eastern is the largest man-made object of its time.
• 11:30PM, Comedy Central - The Colbert Report: Anne-Marie Slaughter, author of The Idea That Is America: Keeping Faith With Our Values In A Dangerous World. Plus, a surprise guest that rhymes with Steagle.