One month after its successful launch, Parker Solar Probe — a NASA’s robotic spacecraft designed to explore the Sun’s atmosphere — has collected and transmitted its first data.
First light data from Parker Solar Probe’s WISPR instrument suite: the right side of this image — from WISPR’s inner telescope — has a 40-degree field of view, with its right edge 58.5 degrees from the Sun’s center; the bright object slightly to the right of the image’s center is Jupiter; the left side of the image is from WISPR’s outer telescope, which has a 58-degree field of view and extends to about 160 degrees from the Sun; it shows the Milky Way, looking at the Galactic center; there is a parallax of about 13 degrees in the apparent position of the Sun as viewed from Earth and from Parker Solar Probe. Image credit: NASA / Naval Research Laboratory / Parker Solar Probe.
“All four instrument suites on Parker Solar Probe — WISPR, ISʘIS, FIELDS and SWEAP — returned data that not only serves for calibration, but also captures glimpses of what we expect them to measure near the Sun to solve the mysteries of the solar atmosphere, the corona,” said Parker Solar Probe project scientist Dr. Nour Raouafi, from the Johns Hopkins University Applied Physics Lab.
“The mission’s first close approach to the Sun will be in November 2018, but even now, the instruments are able to gather measurements of what’s happening in the solar wind closer to Earth.”
As the only imager on the spacecraft, the WISPR (Wide-field Imager for Solar Probe) instrument will provide the clearest-yet glimpse of the solar wind from within the Sun’s corona.
WISPR was turned on in early September 2018 and took test images for calibration.
“There is a very distinctive cluster of stars on the overlap of the two images. The brightest is the star Antares-alpha, which is in the constellation Scorpius and is about 90 degrees from the Sun,” said WISPR principal investigator Dr. Russ Howard, a scientist at the Naval Research Laboratory.
“The Sun, not visible in the image, is far off to the right of the image’s right edge. The planet Jupiter is visible in the image captured by WISPR’s inner telescope — it’s the bright object slightly right of center in the right-hand panel of the image.”
“The left side of the photo shows a beautiful image of the Milky Way, looking at the Galactic center.”
The ISʘIS (Integrated Science Investigation of the Sun) instrument suite aboard Parker Solar Probe measures high-energy particles associated solar activity like flares and coronal mass ejections.
ISʘIS’ two Energetic Particle Instruments cover a range of energies for these activity-driven particles: EPI-Lo focuses on the lower end of the energy spectrum, while EPI-Hi measures the more energetic particles.
Both instruments have gathered data under low voltage, making sure their detectors work as expected. As Parker Solar Probe approaches the Sun, they will be fully powered on to measure particles within the Sun’s corona.
“The ISʘIS team is delighted with instrument turn-on so far. There are a few more steps to go, but so far everything looks great,” said ISʘIS principal investigator Professor David McComas, of Princeton University.
The spacecraft’s FIELDS instrument suite captures the scale and shape of electric and magnetic fields in the Sun’s atmosphere. These are key measurements to understanding why the Sun’s corona is hundreds of times hotter than its surface below.
FIELDS’ sensors include four 2-m electric field antennas as well as three magnetometers and a fifth, shorter electric field antenna mounted on a boom that extends from the back of the spacecraft.
“FIELDS is one of the most comprehensive fields and waves suites ever flown in space, and it is performing beautifully,” said FIELDS principal investigator Dr. Stuart Bale, from the University of California, Berkeley.
The SWEAP (Solar Wind Electrons Alphas and Protons) suite includes three instruments: Two Solar Probe Analyzers (SPAN) measure electrons and ions in the solar wind, while the Solar Probe Cup sticks out from behind Parker Solar Probe’s heat shield to measure the solar wind directly as it streams off the Sun.
After opening covers, turning on high voltages and running internal diagnostics, all three instruments caught glimpses of the solar wind itself.
“SWEAP’s solar wind and corona plasma instrument performance has been very promising,” said SWEAP principal investigator Dr. Justin Kasper, from the University of Michigan.
“Our preliminary results just after turn-on suggest we have a set of highly sensitive instruments that will allow us to do amazing science close to the Sun.”
