The planet also began releasing oxygen, thanks to an ancient adoption of photosynthesis. A very ancestral primitive plant cell either engulfed or tried to digest or surrounded a cyanobaterium and instead of digesting it, it actually became an organ w...
Evidence of the first oxygen in the atmosphere. The gas was released by a humble microscopic living organism called cyanobacteria. Well it turns out cyanobacteria are the only things that can actually produce oxygen, so we know that at some point cya...
We were left with this atmosphere made of molten rock and vaporous rock. It took millions of years for that atmosphere to fall out and to be replaced by an atmosphere made up of nitrogen and carbon dioxide and water vapour. These new gases came from...
Our planet was spared this fate. The magnetic field generated by the Earths core blocked the solar wind, preventing it from blasting away the fragile air. But the Earths atmosphere was still very different from the one we breathe today. It contained...
To discover why these twin planets followed separate paths and to explore what gave us our precious atmosphere, we have to travel back, back four and a half billion years to the birth of the solar system itself. The birth of the solar system created...
In contrast, Jupiter and Saturn are all atmosphere. Unlike Earth, Jupiter doesnt really have a solid surface that you could stand on and then have your head up in the atmosphere looking at the clouds. Its just a giant, giant gas ball. Only one other...
英语听力,探索发现,科学新发The mission had been a stunning success: Kittinger skydiving record stands to this day. He takes his first deep breath of air with a new found appreciation for our atmosphere. It was relief to be back on the plan...
Kittinger is in the mid stratosphere, a record 102,800 feet high. And it is now the time to make the long, swift journey down. When it came time for me to jump, I was ready to jump because I was heading back toward a more friendly environment, a frie...
My crew chief said, are you ready? I said, Im ready, lets go. It was a very smooth take-off and I started ascending up, up, up. 30 minutes after take-off, Kittinger reaches 29,000 feet, the middle of the troposphere. At this altitude, the air is so t...
Our chemistry, our very nature, our metabolism is completely shaped by the atmosphere. To appreciate our atmosphere, well rise through its layers, travelling from the planets surface, miles up above mountains and the clouds, to the very edge of space...
In the empty blackness of space surrounded by hostile planets and freezing vacuum, planet Earth is an oasis of life. And all because of our protective cocoon of gas. This blanket of air shapes everything we see on Earth. It protects, insulates and su...
When you consider the Earths history stretching over billions of years, its clear that meteorite impacts, far from being unexpected, are just a normal part of the life cycle of our planet. But that is not how they seem to us. The Chebarkul meteorite...
It came in in the daytime sky out of the Sun. Weve got telescopes looking out there for these objects, but they only work at night. Radar doesnt help either because to really use radar to find these objects above the atmosphere, you have to know exac...
Approaching from beneath the planet, asteroid 2012 DA14 passed inside the orbit of our geostationary satellites before heading off to the north. This asteroid had been successfully tracked for a year. And despite its proximity, scientists knew that i...
An asteroid strike would create a huge explosion. NASA feared this might even be mistaken for a nuclear bomb. We wanted folks to know this was a natural event by Mother Nature rather than some sort of man-made event like a missile or something dreadf...
