Imagine an object moving at super-sonic speed. This object, as it moves through a medium, causes the material in the medium to pile up, compress, and heat up. The result is a type of shock wave, known as a bow shock.
Permafrost in the coldest northern Arctic -- formerly thought to be at least temporarily shielded from global warming by its extreme environment -- will thaw enough to become a permanent source of carbon to the atmosphere in this century, with the peak transition occurring in 40 to 60 years, according to a new NASA-led study.
In the 1980s, scientists started discovering a new class of extremely bright sources of X-rays in galaxies. These sources were a surprise, as they were clearly located away from the supermassive black holes found in the center of galaxies. At first, researchers thought that many of these ultraluminous X-ray sources, or ULXs, were black holes containing masses between about a hundred and a hundred thousand times that of the sun. Later work has shown some of them may be stellar-mass black holes, containing up to a few tens of times the mass of the sun.
Much like detectives study fingerprints to identify the culprit, scientists used NASA’s Hubble and Spitzer space telescopes to find the “fingerprints” of water in the atmosphere of a hot, bloated, Saturn-mass exoplanet some 700 light-years away. And, they found a lot of water. In fact, the planet, known as WASP-39b, has three times as much water as Saturn does.
How would you search for signs of life – traces of tiny, living microbes or their fossilized remains – in an extreme and distant environment? NASA scientists and engineers are working on an answer to that question, aiming to find out if life ever evolved on the planet Mars and if it still harbors life today.
A NASA study based on an innovative technique for crunching torrents of satellite data provides the clearest picture yet of changes in Antarctic ice flow into the ocean. The findings confirm accelerating ice losses from the West Antarctic Ice Sheet and reveal surprisingly steady rates of flow from its much larger neighbor to the east.
The planet Mars has fascinated scientists for over a century. Today, it is a frigid desert world with a carbon dioxide atmosphere 100 times thinner than Earth’s. But evidence suggests that in the early history of our solar system, Mars had an ocean’s worth of water. NASA’s James Webb Space Telescope will study Mars to learn more about the planet’s transition from wet to dry, and what that means about its past and present habitability.
Last year was a record-breaking one for Operation IceBridge, NASA’s aerial survey of the state of polar ice. For the first time in its nine-year history, the mission, which aims to close the gap between two NASA satellite campaigns that study changes in the height of polar ice, carried out seven field campaigns in the Arctic and Antarctic in a single year.
NASA’s next planet-hunting mission has arrived in Florida to begin preparations for launch. The Transiting Exoplanet Survey Satellite (TESS) is scheduled to launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station nearby NASA’s Kennedy Space Center in Florida no earlier than April 16, pending range approval.