Group items tagged

A quick mini-experiment that can help kids to learn about the density of air and the impact that temperature has on density. Similar to the balloon/bottle experiment that I already do in class.

A good mini-lab that can be used to teach kids about density.

This got us thinking: What happens when smaller (and bigger) objects fly into our atmosphere? We used Purdue University's "Impact: Earth!" simulator to find our answers. Our own Bob Al-Greene illustrated the results, as seen in the gallery above.

Some highlights: Rocks the size of basketballs enter our planet about once a month; most burn apart in the atmosphere before they reach the surface. Objects as long as standard school buses (roughly 12 meters around) only sneak into the Earth every 20 years or so - but, as seen in Chelyabinsk, the damage can be much greater.

All results assume the object is traveling at a 45-degree angle, with a density level of 3000 kg/m^3 and a velocity of 11 km/s. Everything is assumed to be seen from 100 kilometers away from the direct impact zone.

Click "Show As List" on the bottom-left of the gallery to view larger images. And check out our Google Hangout with asteroid experts to learn more about what's being done to fend off space rocks, from basketball-sized to London-sized.