Comets • 2007 Planet Science

Category: Astronomy
Download:

Scientists are only now starting to unravel the secrets of comets. Often referred to as dirty snowballs, they contain ice and elements from the very start of the universe. Some theorize that a comet, crashing into our planet, brought with it the organic material that started life on Earth. Spacecraft continues to offer new information on their makeup, from bringing back samples from a comet's tail to direct contact when a NASA-launched craft slammed into the comet Tempel-1.

Planet Science • 2007 • 1 episode •

Comets

Scientists are only now starting to unravel the secrets of comets. Often referred to as dirty snowballs, they contain ice and elements from the very start of the universe. Some theorize that a comet, crashing into our planet, brought with it the organic material that started life on Earth. Spacecraft continues to offer new information on their makeup, from bringing back samples from a comet's tail to direct contact when a NASA-launched craft slammed into the comet Tempel-1.

2007 • Astronomy

You might also like

Deadly Meteors

Impacts from space have created our planet and just about everything in it. Like celestial supply ships, they brought in water, metal, and maybe even life. They made our moon and sculpted the geography of our planet.

12/17Big History • 2013 • Astronomy

Terraforming Mars

Could human settlements on Mars become reality as early as 100 years from now? Artificial micro organisms created with the latest techniques in synthetic biology could be used to produce resources such as iron, energy, and food directly on the planet itself. What would this new "Earth" look like?

1Cosmic Front • 2014 • Astronomy

Ultimate Mission

The Apollo space program embraces tragic setbacks and historic success; the last stage includes the Apollo 11 space flight which landed the first two people on the Moon.

2/2Apollo Back to the Moon • 2019 • Astronomy

Mars Alien Secrets

The latest NASA missions to Mars might finally reveal if it is home to alien life, and using these brand-new discoveries, experts are rethinking everything they know about the Red Planet.

Space's Deepest Secrets • 2019 • Astronomy

Low Mass Stars

Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years.

29Crash Course Astronomy • 2015 • Astronomy

Asteroids

Most major geological processes require millions of year to become noticeable. Meteor impacts are exceptions which can cause comparable changes in seconds.

S1E10How the Earth Was Made • 2009 • Astronomy