Launched in 2018, the mission aims to study the sun and reveal some of its mysteries. Over the course of seven years, the probe will travel through the sun’s atmosphere and get closer to the surface of our star than any spacecraft before it.
Venus is essential to the success of the probe. The spacecraft uses Venus’s gravity as it swings around the planet, a so-called gravity assistant, to help bend the probe’s orbit and move it closer and closer to the sun.
The spacecraft’s WISPR instrument, or Wide-field Imager for Parker Solar Probe, actively took images while in flight and captured the night side, or the side facing away from the sun, of Venus. The photo was taken 7,693 miles from the planet.
Bright streaks in the image are the result of space dust and cosmic rays, or charged particles, reflecting sunlight. The stripes look a little different depending on how fast the probe is traveling.
There is also a noticeable dark feature in the center of the image. It is known as Aphrodite Terra, the largest highland area on Venus. The reason it looks so dark in the image is because it actually has a temperature that is 85 degrees Fahrenheit lower than the surrounding areas.
The WISPR instrument is designed for the probe so that it can collect images of the sun’s corona, or the outer atmosphere, in visible light. The camera can also capture the solar wind in action. The solar wind is a steady stream of activated particles flowing from the sun.
When WISPR looked at Venus, it surprised the team’s scientists. Instead of seeing clouds, the surface of Venus was revealed. Venus has an incredibly thick atmosphere that in the past has proven difficult to see through with instruments on other spacecraft.
“WISPR has effectively captured the thermal emission from the Venusian surface,” Brian Wood, an astrophysicist and WISPR team member at the US Naval Research Laboratory in Washington, DC, said in a statement.
What WISPR could do in visible light is similar to what Akatsuki captured from Venus in near-infrared, Wood said.
Angelos Vourlidas, the project scientist for WISPR at Johns Hopkins Applied Physics Laboratory in Maryland, coordinated an imaging campaign with the Akatsuki mission.
One of two things happens. Either WISPR is actually sensitive to infrared light and picks it up when it passes Venus – which could provide opportunities to study dust around the sun, or the camera looks through Venus’ atmosphere and straight to the surface.
Parker Solar Probe just made its fourth flyby of Venus on Feb. 20, passing 1,482 miles from the planet’s surface, so the team planned another series of observations of the Venusian night side. That data should be received by the end of April, according to NASA.
Each pass of the sun causes the probe to break its own previous record, more than a million miles closer than the previous pass. These passes take the probe 10.5 million miles from the sun’s surface.
“We are very much looking forward to these new images,” said Javier Peralta, an astrophysicist with the Akatsuki team. Peralta was the first to propose a Parker Solar Probe collaboration with the Japanese mission.
“If WISPR can detect the thermal emission from the surface of Venus and nightglow – most likely from oxygen – at the edge of the planet, it could make valuable contributions to studies of the surface of Venus.”