Fifty years after first conceived, NASA is scheduled to begin its historic mission to “touch the sun.” The Parker Solar Probe launches from Cape Canaveral on Saturday and, if successful, will travel seven times closer to the sun than any other spacecraft, at 3.8 million miles from the surface.
“We’re going to a place that is virtually unexplored. It’s a new frontier,” said James Garvin, chief scientist for NASA’s Goddard Space Flight Center.
Despite humanity’s reliance on the star, there is a lot we don’t know about it, he said. The probe will explore the sun’s process of heating its outer atmosphere, also known as its corona, as well as how solar wind is accelerated.
Scientists want to know why the corona is 300 times hotter than the surface of the sun. The current theory is regular tiny explosions of plasma from the surface of the sun power the corona, NASA's website stated.
The corona is unstable, generating solar winds through solar flares and mass ejections that bombard the earth with radiation, interfering with satellites, which are used for everything from keeping time to geolocation. The coronal flares have also historically caused surges in power lines, damaging the electrical grid.
“By understanding exactly how these particles are accelerated we will be able to predict with more reliability when these storms are occurring and how intense they will be,” said Mihir Desai, Southwest Research scientist and co-investigator on the Parker Solar Probe.
That’s impossible currently because by the time the particles reach Earth’s atmosphere they are all mixed up, he said.
“Going in closer is really the key to untangling these effects,” he said
The probe will fly into the outer corona and is only able to get that close because of modern engineering, Garvin said. The probe will have a 4.5 inch thick carbon composite shield, as well as a cooling system keeping instruments at room temperature while engulfed in temperatures reaching 2,500 degrees fahrenheit.
Over the course of seven years, the probe will orbit the sun two dozen times. It will use the planet Venus to adjust its orbit and fly ever closer to the sun, eventually reaching a top speed of 430,000 miles per hour.
“It’s a quick dance into that special region of the sun that we need to sample, explore, measure and get to know because that’s where all the good stuff happens,” said Garvin, describing the mission as one of the most elaborate trajectories ever.
The mission is scheduled to launch Saturday at 2:33 a.m. on a Delta IV rocket. The launch window for the mission was extended last week to Aug. 23 if delayed.
Paul Flahive can be reached at paul@tpr.org or on Twitter @paulflahive
