Science

How NASA protects its solar probe from the Sun

How NASA protects its solar probe from the Sun

The United States space agency NASA is preparing to launch a probe on Saturday to study the Sun closer than any other human-made object before, revealing mysteries behind the fiery surface.

NASA will be livestreaming the launch of the Parker Solar Probe, early Saturday morning.

By sampling the environment of the corona, the Parker Solar Probe will help answer some key questions about our home star - perhaps most importantly, why is the Sun's corona, which can reach temperatures into the millions of degrees, so hot compared to the Sun's surface, which has a temperature of roughly 6,000 degrees. The Solar Probe Cup, dubbed "the bravest little instrument", is a sensor that will extend beyond the heat shield to "scoop up samples" of the sun's atmosphere, according to Justin Kasper, mission principal investigator and professor of climate, space sciences and engineering at the University of MI. It is equipped with a Northrup Grumman solid-fuel upper stage that will act to drop the Parker probe out of Earth's 18-mile-per-second orbit around the sun, allowing it to fall inward for the first of seven gravity assist flybys of Venus over a planned seven-year mission.

NASA plans to try again before dawn Sunday to launch a $1.5 billion mission from Cape Canaveral that aims to send a science probe closer to the sun than any spacecraft before.

Nearly everything on the spacecraft will be behind this and thus in room-temperature shade while ducking through the jagged edges of the corona, without so much as a blister on its science instruments.

The Parker mission has been a work in progress for decades, with technology only recently yielding material strong enough to withstand a red-hot flyby, said project scientist Nicky Fox of Johns Hopkins University's Applied Physics Lab.

You've already heard plenty about the Parker Solar Probe over the past year or so, and with good reason. And what powers the solar wind, the stream of charged particles that flows outward from the corona at speeds on the order of a million miles per hour? Solar wind can reach speeds of 1.8 million miles per hour - but how the particles are accelerated to such speeds remains a mystery. The probe will pass by Venus seven times, losing a little energy with each pass to settle down into its final orbit around the Sun.

The satellite will come within 3.8 million miles of the sun by December 2024.

This historic mission sets out to unravel some of the biggest puzzles regarding our sun, its scorching outer atmosphere known as the solar corona, and the solar wind - the mysterious outflow of charged particles it oozes into the solar system.

An artist's rendition of the PSP venturing close to the Sun's surface. Among the properties that it will be measuring regularly are the electric and magnetic fields present, along with the velocity, density, and temperature of particles that typically make up solar wind-protons, electrons, and heavier ionized nuclei. The current close-to-the-sun champ, NASA's former Helios 2, got within 27 million miles (43 million kilometers) in 1976. Sixty years ago, the young astrophysicist proposed the existence of solar wind.

Just outside the Sun's atmosphere lies the emptiness of space.

"I'm greatly honored to be associated with such a heroic scientific space mission", Parker said.

"We can't agree on what's actually going on", Kasper said. "It's very exciting that we'll finally get a look". I'm sure that there will be some surprises.