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What Google's self-driving car sees

Charlie Warzel: "THIS is what google's self driving car can see. So basically this thing is going to destroy us all." [via Matt Buchanan]

Another satellite will re-enter Earth's atmosphere in the coming months

In case you were curious, that atmospheric research satellite crashed to Earth without hitting a single person. It landed in the Pacific—scattering bits and pieces over an 800-mile-long stretch of ocean.

But, if your great dream was to be killed by a piece of falling satellite, never fear. Phil Plait points out that you'll have another chance in a couple of months, when the German X-Ray astronomy satellite ROSAT is expected to meet its firery end.

Smaller than UARS — a little over 2 tons, as opposed to over 6 — ROSAT will probably have more pieces survive the ride down because its mirrors had to be shielded from heat to operate. That means the odds of it hitting someone will be slightly higher than from UARS, about 1 in 2000. Bear in mind that’s still really small odds! The chance of a specific individual getting hit are still something like only 1 in 14 trillion.

Earth's Trojan asteroid

The green circle in the lower right of this image marks the position of Earth's own trojan asteroid, discovered by researcher's involved with NASA's Wide-field Infrared Survey Explorer project.

What's a trojan asteroid? Glad you asked. The good news: It's not going to kill us all.

Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.

Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view.

The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.

The asteroid is roughly 1,000 feet (300 meters) in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 50 million miles (80 million kilometers) from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 15 million miles (24 million kilometers).