We're heading to Mars. Eventually. Before we can land people on the surface of the Red Planet, we first have to figure out how to get them there safely. Thursday should mark a major milestone in that effort as NASA sends its next-generation Orion spacecraft up for its maiden flight test.
Orion will be riding a massive Delta IV Heavy rocket into space, where it will orbit the planet twice before reentering through the atmosphere and heading for a watery splashdown in the Pacific Ocean. This will be the first time Orion's heat shield will have been put to an operational test to see how it stands up to 4,000-degree temperatures. The Delta IV Heavy is the largest rocket the US has available. It will need that power to get the combined 1.63 million pounds of fuel, spacecraft and equipment off the launch pad.
"Really, we're going to test the riskiest parts of the mission," said Mark Geyer, Orion program manager, in a statement. "Ascent, entry and things like fairing separations, Launch Abort System jettison, the parachutes plus the navigation and guidance -- all those things are going to be tested. Plus we'll fly into deep space and test the radiation effects on those systems."
Orion is expected to hit a peak altitude of 3,609 miles, which is considerably higher than the International Space Station. Scientists will be studying how Orion holds up to radiation exposure at this height. The whole journey will take about 4.5 hours.
Information gathered from the test flight will help NASA refine the spacecraft's design. Plans are to use the Orion spacecraft to transport human crew members to far-off locations. NASA has its sights set on visiting an asteroid and eventually reaching Mars, though that goal is a long way off. In the nearer future, NASA intends to send Orion on an uncrewed mission around the moon within the next few years.
Current forecasts from meteorologists are giving NASA a 60 percent chance for acceptable launch conditions on Thursday morning. There is a possibility of rain, which could force the launch to take place on another day. NASA is prepared to try again on Friday or Saturday if the planned Thursday lift-off doesn't work out.
NASA TV will be offering live coverage of the launch starting at 1:30 a.m. PT, if you want to be able to say you were watching when humankind took a major step toward putting people on Mars.