On March 30, the first stage of a Falcon 9 rocket sent its second payload into space, after having launched and landed in April 2016. This achievement is an important milestone in the company's road to creating a reusable launch system—and a feat that's 15 years in the making. The launch and subsequent landing on a drone ship proves, as SpaceX CEO Elon Musk noted, "you can fly and re-fly an orbit-class booster."
About four billion years ago, Mars was warm. Water flowed in lakes and rivers under a nice thick blanket of atmosphere. But then something cataclysmic happened. Mars' insulating atmosphere all but disappeared. Exposed to the harsh elements of space, the red planet became the dry, frozen wasteland that it is today.
Imagine you're at a beach, standing near the dunes and looking out on a peaceful sea. The dry sand squishes through your toes, and you decide to build a sandcastle near the shore, without using any liquid to bind the grains together. A few weeks later, you wander back the same way, and your sandcastle is still there.
In 2024 the clock will run out on the International Space Station. Maybe. That's the arbitrary deadline that Congress imposed back in 2014, at which point they'll have to decide whether or not to keep funding the ISS. And yeah, that's a whole seven years away. But then again...it's only seven years away.
Since August of 2012, NASA's Curiosity Rover has tooled around the red planet doing science for us Earthlings. Now, nearly five years and some 10 miles later, the robot is starting to experience the wear and tear of an aging machine: On Tuesday, NASA announced the first two breaks in the rover's wheel treads.
On July 10th, 2015, a chunk of cliff with the same volume as nine Olympic-sized swimming pools tumbled from its perch on Comet 67P. A month later, the comet would reach its perihelion, the closest its elliptical orbit passes to the sun. As the sun's rays reached the Aswan cliff section of Comet 67P's northern hemisphere, the rapid change in temperature warmed the cliff from -220 degrees Fahrenheit to 122 degrees Fahrenheit in the space of about 20 minutes. One percent of the cliff's mass was lost to space, a great jetting plume cast off like water after a dive, and the boulder-like formations settled into a new ridge at the foot of the cliff. We know all of this drama in the heavens thanks to a paper published today in Nature Astronomy.