Parker Solar Probe now closer to the Sun than any spacecraft in history
The Parker Solar Probe has only been in space about two and a half months, and it's already breaking records. On October 29, 2018 at 1:04 pm EDT, the unmanned spacecraft came within 26.55 million mi (42.73 million km) of the Sun's surface – closer than any other man-made object.
In April 1976, the German-American Helios 2 spacecraft set the previous record for the closest spacecraft, as well as the fastest speed relative to the Sun at 153,454 mph (246,960 km/h). According to NASA, the Parker Solar Probe has not only broken the proximity record, but also broke the speed record on October 29 at 10:54 pm EDT and will continue to break records as it approaches the Sun and ultimately comes within 3.83 million mi (6.16 million km) of the surface in 2024.
The speed of the Parker Solar Probe was measured using NASA's Deep Space Network (DSN), which sends radio signals to the spacecraft that are then retransmitted back to Earth. By studying such factors as return time and Doppler shifts, the Parker team can calculate its speed and position, and project these into the future.
"It's been just 78 days since Parker Solar Probe launched, and we've now come closer to our star than any other spacecraft in history," says Project Manager Andy Driesman, from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. "It's a proud moment for the team, though we remain focused on our first solar encounter, which begins on October 31."
This first solar encounter will see the probe approaching its first perihelion – the point closest to the Sun – which will occur on November 5, 2018 at 10:28 pm EDT, when it will be subjected to heat and radiation greater than has been encountered by any deep space probe. The purpose of the mission is to gain a better understanding of the Sun and its effect on the Earth and other planets.