When a pilot spotting nine shiny flying objects near Mount Rainer on June 24, 1947, the newspapers dubbed them "flying saucers" and speculation ran rampant that aliens from Mars were keeping tabs on Earth.
It was the first documented "sighting" of a flying saucer (actually, the pilot described them as crescent shaped, but said they moved like a saucer skipping over water). Since then the sleek, gravity-defying look of flying saucers has made them an icon of science fiction speculation. Now they might be fact: NASA is set to test their own version of a flying saucer to be sent to Mars.
This week NASA hope to launch a test flight of its Low-Density Supersonic Decelerator (LDSD), according to a press release. The test was originally scheduled for June 2 but weather has kept the vehicle grounded. Weather provoked cancelations again on June 3 and June 4, but the launch window is open until June 12.
The LDSD looks like a puffy, slightly flattened hamburger. It’s disc shape and inflatable balloon ringing the outside are designed to help slow the vehicle down as it lands in the comparatively thinner atmosphere of Mars, reports Loren Grush for Popular Science. An additional parachute can slow the craft even more. Grush writes:
Mars’ air doesn’t create enough drag, meaning super heavy payloads will pick up a lot of speed from Mars' gravity on the way down, potentially crashing into the surface. Currently, NASA only knows how to land about one metric ton on Mars at a time, but they’ll need to land more than that if they want to establish any kind of long-term human settlements there.
The June test is an attempt to fly the saucer into near-space above the Pacific Missile Range Facility in Hawaii and then land it slowly. At first, a high altitude balloon will bear the saucer aloft, up to about 120,000 feet. Then the craft will drop from the balloon, ignite four small rockets to spin stabilize its fall. Two seconds later, a Star 48B long-nozzle, solid-fueled rocket engine will thrust the craft up to 180,000 feet, or the edge of the stratosphere, at a speed of about Mach 4. Kim Newton explains for NASA’s blog:
At about Mach 3, the test vehicle will deploy the supersonic inflatable aerodynamic decelerator (SIAD). The SIAD decelerates the vehicle to approximately Mach 2.4. The test vehicle will then deploy a large supersonic ringsail parachute, which will further slow the test vehicle to a controlled water impact landing about 40 minutes after being dropped from the balloon.
All the action will be broadcast live via NASA TV on the streaming video service Ustream. NASA walked through the details of what will be broadcast in another statement, but the short version is that the action will really start when the saucer drops from the balloon. The statement explains:
[V]iewers will see live, low-resolution images from high over the Pacific Ocean off the west coast of Kauai, Hawaii. Four cameras aboard the test vehicle will provide the LDSD mission team with different perspectives on the test. Two of the cameras provide views of the rim of the test vehicle and will show the performance of the Supersonic Inflatable Aerodynamic Decelerator (SIAD). A third camera will show the rocket motor firing, with Earth's horizon spinning in the background (the vehicle is spin-stabilized during the rocket flight), along with the deployment of the parachute's lanyards. The fourth camera looks directly up and will show the deployment of the ballute and supersonic parachute.
"What we will be looking most closely for is to see what happens on that fourth camera, when at Mach 2.35 our supersonic parachute is deployed," said Adler. "It may be hard to see because the transmitted video is low resolution, but we hope to be able to make it out."
That weather balloon phase makes wind speed and direction critical for a successful launch. Rough seas can also make craft retrieval tricky. If this launch window doesn’t work, another one opens July 7 through 17.
Keep updated on the status at the NASA blog and get ready to tune in when the launch is GO.