The Parker Solar Probe sees Venus’s orbital dust ring in the first full image

NASA’s Parker Solar Probe mission has given scientists a first full look at Venus’s orbital dust ring, a collection of microscopic dust particles circulating around the sun along Venus’ orbit. While previous missions have made some observations of Venus’s orbital dust ring, the Parker Solar Probe images are the first to show the planet’s dust ring nearly its full 360 degrees around the sun.

Parker Solar Probe’s WISPR instrument – short for Wide-field Imager for Solar Probe – is designed to study the solar wind, the constantly emanating material from the sun. The room is teeming with dust, which reflects so much light that it usually shines at least a hundred times brighter than the solar wind. (The light reflected from space dust is what creates the zodiacal light, sometimes visible from Earth as a faint column of light rising from the horizon.)

To see the solar wind with WISPR, scientists use image processing to remove the dust background and stars from the images. This process worked so well that Venus’s orbital dust ring – which appears as a bright band extending across the images – was also subtracted. It wasn’t until Parker Solar Probe performed rolling maneuvers to control its momentum on its way to its next solar fly, which changed the orientation of its cameras, that the static ring of dust was noticed by scientists. Based on the relative brightness, scientists estimate that the dust along Venus’ orbit is about 10% denser than in adjacent regions. The results were published on April 7, 2021 in The Astrophysical Journal

The German-American spacecraft Helios and NASA’s STEREO mission – short for Solar Terrestrial Relations Observatory – have both made previous observations of the dust ring along Venus’ orbit. Those measurements have enabled scientists to develop new models of the origin of matter along Venus’ orbit. The sensitive imaging devices and unique orbit of Parker Solar Probe have given scientists an unprecedented glimpse into the dust ring of Venus – something the science team has been pursuing since the early days of the mission.

As the Parker Solar Probe flies closer to the sun over the course of its mission, the science team also expects to make the first observations of a long-believed dust-free zone, an area close to the sun where dust has been heated and evaporated by the intense sunlight. If there is a dust-free zone near the Sun – an idea supported by areas of thinning dust that Parker Solar Probe has observed from afar – this would not only confirm theories about the interaction between our star and the nearby dust, but Astrophysicists also help those studying more distant objects: Just as space dust can disrupt seeing the solar wind, it can also obscure measurements of stars and galaxies.

However, the dust itself is of interest to many scientists. For example, the exact origin of the dust that fills the solar system is not a fixed science. For decades, scientists have largely thought that the dust is debris from comets and asteroids – but new research using data from NASA’s Juno mission to Jupiter suggests that dust storms on Mars may be the source of much of the solar system’s dust.

Space dust can also form the building blocks of stars and planets, transport gases between galaxies, and provide a nurturing environment for young planets. These were some of the questions in mind for scientists on the DUST sounding rocket mission – short for Determining Unknown but Significant Traits – launched in 2019 to investigate how dust particles coagulate in the microgravity of space.