5 Incredible Discoveries

5 most incredible discoveries of the week

Two revelations about the moon were among the week's more intriguing discoveries:

1. The Moon Isn't Round:  It Bulges like a Lemon: We may have walked on it 45 years ago, but scientists have only now discovered the true shape of Earth's moon. And while it might look like a perfect sphere, it's actually "like a lemon with an equatorial bulge," says one researcher. The reason has to do with an ancient tidal surge.

2. Moon Might Hold Fossils From Earth: Might the moon is able to shed some light on the origins of life on Earth? A new study shows it's possible that fossils from our planet could have survived the trip there via meteorite. And those fossils might hold clues that can no longer be found on Earth.

3. Tree Rings Solve Mystery of World Trade Center Ship: A mystery ship unearthed during construction of the new World Trade Center site isn't so much of a mystery anymore. A study based on analysis of tree rings in its wood reveals that the ship likely got built in 1773 in Philadelphia. Fittingly, the wood has a connection to the construction of Independence Hall.

4. Deep-Sea Octopus Guards Eggs for 4 Years without Food: Talk about endurance. Scientists say they've observed a deep-sea octopus in California guarding her eggs for 4.5 years, the longest known brooding or gestation period of any animal anywhere in the world. She did so with little or no food.

5. Running Just Minutes a Day May Cut Death Risk: Good news for those who keep meaning to exercise, but can never seem to find the time: If you can manage a few minutes of running a day—even going slowly—you may cut your risk of death from cardiovascular disease.