The mission, which launched in 2018, aims to study the sun and uncover some of its secrets. Over the course of seven years, the probe will travel through the sun’s atmosphere and move closer to the surface of our star than any spacecraft before it.
Venus was instrumental in the success of the probe. The spacecraft uses Venus’ gravity as it swinges around the planet, called gravity assist, to help bend the orbit of the probe and bring it closer to the sun.
The spacecraft’s WISPR instrument, or Parker Solar Probe’s Wide Field Imager, was taking active images in flight and capturing the night side, or the sun-facing side, of Venus. The image was taken 7,693 miles from the planet.
The bright lines that appear in the image are the result of space dust and cosmic rays, or charged particles that reflect sunlight. The lines look slightly different depending on how fast the probe is moving.
There is also a noticeably dark feature in the center of the image. Known as Aphrodite Terra, it is the largest highland region on Venus. The reason it appears so dark in the image is that it is actually at a temperature less than 85 degrees Fahrenheit than the surroundings.
The probe’s WISPR instrument is designed to collect images of the solar corona, or the outer atmosphere, in visible light. The imager can also capture the solar wind in action. The solar wind is a constant stream of energetic particles flowing from the sun.
When WISPR turned to look at Venus, the team’s scientists were stunned. Instead of seeing clouds, the surface of Venus is revealed. Venus has an incredibly thick atmosphere, and it has proven difficult in the past to display it with instruments on other spacecraft.
“WISPR has effectively captured the thermal emissions of the surface of Venus,” said Brian Wood, an astrophysicist and WISPR team member from the US Naval Research Laboratory in Washington, DC, in a statement.
Wood said what WISPR was able to do in visible light is similar to what Akatsuki captured of Venus in near infrared.
Angelos Vourlidas, a WISPR project scientist at the Johns Hopkins Applied Physics Laboratory in Maryland, coordinated a photography campaign with the Akatsuki mission.
One of two things that happen is either that WISPR is already sensitive to infrared and captures that as it passes through Venus – which could open up possibilities for studying dust around the sun, or that the photographer is looking through Venus’s atmosphere down to the surface.
Parker Solar Probe just made its fourth flight to Venus on February 20, passing 1,482 miles from the planet’s surface, so the team planned another set of observations on the Venusian nocturnal side. This data should be received by the end of April, according to NASA.
Each pass of the sun leads the probe to break its previous record, as it approaches more than a million miles from the previous pass. These corridors will place the probe 6.5 million miles from the surface of the sun.
“We’re really looking forward to these new images,” said Javier Peralta, an astrophysicist with the Akatsuki team. Peralta was the first to suggest Parker Solar Probe’s cooperation with the Japanese expedition.
“If WISPR can sense heat emission from the surface of Venus and night glare – most likely from oxygen – at the planet’s fringes, then it could make valuable contributions to studies of the surface of Venus.”