On Feb. 6, at about 14:00 UTC, a tiny chunk of interplanetary material plunged into Earth’s atmosphere and burned up—likely exploding—about 30 kilometers above the Atlantic Ocean. The energy released was equivalent to the detonation of 13,000 tons of TNT, making this the largest such event since the (much larger) Chelyabinsk blast in February 2013.
OK, so first, off: Don’t panic! As impacts go, this was pretty small.* After all, you didn’t even hear about until weeks after it occurred. Events this size aren’t too big a concern. Had it happened over a populated area it, would’ve rattled some windows and probably terrified a lot of people, but I don’t think it would’ve done any real damage.
For comparison, the Chelyabinsk explosion, which was strong enough to shatter windows and injure more than 1,000 people (due to flying glass), had an equivalent yield of 500,000 tons of TNT, 40 times the energy of this more recent impact.
The event was reported on the NASA/JPL Near-Earth Object Fireball page, which lists some of the brightest such things.
A little background: The Earth is bombarded by debris from space to the tune of about 100 tons every day. Most of this stuff is quite small, like the size of a grain of sand or smaller, and burns up 100 kilometers or so off the ground. We call the solid bit of debris a meteoroid, the bright phenomenon a meteor, and, if it hits the ground, a meteorite.
If the piece is bigger, it can get deeper into our atmosphere before burning up. Moving at orbital speeds, they can enter our atmosphere from roughly 10–100 kilometers per second. For comparison, a typical rifle bullet moves at 1 kps. As they plow into the air, they compress the gas in front of them violently, heating it up. This in turns heats up the meteoroid, which starts to glow. Material can vaporize and blow off (this is called “ablation”), and usually within seconds the meteoroid is either slowed so much it no longer glows, or it vaporizes entirely.