5 Most Incredible Discoveries of the Week

Unprecedented discoveries in space (though this one isn't confirmed) and under the ice of Greenland highlight this week's list:

• Astronomers May Have Found a Milestone Moon: Astronomers have found plenty of Earth-like planets out there in deep space, but so far they haven't found a moon orbiting one of them. Until now, maybe. Scientists might have detected one in orbit around a planet in the constellation Sagittarius.
• Big Find Under Greenland's Snow: 100B Tons of Water: As far as discoveries go, this one is literally huge: An aquifer holding more than 100 billion tons of water that covers an area larger than West Virginia has been discovered beneath Greenland's snow-covered ice sheet. But the discovery seems to raise more questions than it answers.
• Women May Get More Out of Flu Shots: Women react more strongly to flu vaccination than men, a new study has demonstrated, meaning they might be more protected against getting sick. It's possible the trait goes back to our hunter-and-gatherer origins.
• This Is Earth's Hottest Pepper: The Carolina Reaper has taken the title of world's hottest pepper, after a four-year quest to do just that. The Guinness Book of World Records in November handed the honor to Ed Currie, who grows the fire-engine red peppers in South Carolina. The measurement of "Scoville Heat Units" is mind-boggling.
• Narcolepsy Breakthrough: It's Autoimmune: A group of researchers has finally found evidence to confirm what many have long suspected: Narcolepsy is an autoimmune disease. The discovery comes thanks to a vaccine for swine flu.

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