A ring full of dust that surrounds the Sun along the orbital path of Venus has just been revealed in great detail, thanks to the instruments carried by the Parker solar probe.
The clean, white-light images taken from inside the orbit of Venus show the ring almost entirely. These are vital data for understanding this ring and the dynamics of the solar system and its gravitational interactions.
“This is the first time that a ring of circumsolar dust from the inner solar system could be revealed in all its splendor in” white light “images,” said astronomer Guillermo Stenborg of the US Naval Research Laboratory. “I find it quite special.”
(Stenborg et al.)
The solar system is a really dusty place. The whole thing consisted of dust (and gas); much of the dust has been integrated into planets and asteroids and what not (not to mention the Sun); he often shook himself again.
Asteroids and comets resemble cosmic salt and pepper shakers, spraying their space wherever they go. Recent research has found that Mars could spray things everywhere during the huge global storms that occur every year.
All this dust can simply move, but sometimes it can be caught in orbital resonance with a planet; that is, it orbits along the same path, with an orbital period that has a relationship with a single integer with that of the planet.
The earth has a significant ring of resonant dust; scientists have recently found evidence that Mercury also has one. And the dust ring of Venus has been known, and even partially observed, by the German-American solar mission Helios and the solar mission of NASA STEREO, for some time.
Cue Parker Solar Probe, equipped with a tool called Wide-field Imager for Solar Probe (WISPR). WISPR consists of two heliosphere images with visible light designed to imagine the interplanetary environment to study the solar wind – the constant flow of charged particles emanating from the Sun.
Because interplanetary dust is so bright with reflected sunlight, it exceeds the solar wind, so special image processing is applied to remove background noise from solar wind observations. This also means that WISPR is uniquely able to observe the resonant dust ring of Venus.
Of course, during normal operations, the dust ring will be automatically extracted from the data. Parker performed a few rolling maneuvers in August and September 2019 to manage its momentum, which caused the WISPR cameras to move – and a brilliant series to appear in the resulting images.
At first, astronomers thought it was something else, such as a bright helmet streamer shooting from an active region of the Sun or even an image processing error. It was far too big to be a headset streamer, and image processing oppositions were also ruled out. The next step was to look at what else is in that space and then they found that the stripe aligns perfectly with the orbit of Venus.
Because the brightness is also consistent with the scattering of light by dust, the team concluded that the most likely explanation is the planet’s resonant dust ring.
The data could be extremely useful. Scientists believe that interplanetary dust could be a mechanism for transporting molecules from the solar system, a means by which materials spilled from asteroids or comets make their way to other bodies.
We still don’t know how these dust rings formed or where they come from, though, so the more information we have, the closer we can get to figuring them out.
“One idea is that dust rings formed naturally from the primordial cloud, but several researchers claim that each planet’s gravity gradually caught particles, perhaps even asteroids or comet particles from its orbit,” explained astrophysicist Russell Howard. from the US Naval Research Laboratory. .
Another possibility is that the dust rings are constantly turned; collisions between grains could take some of the old dust out of orbit, while new dust arrives from another.
There is another mystery with the Venus ring. Analysis of data from previous observations suggested that there was much more dust in the resonant ring of Venus than could easily be explained. A team of researchers recently performed some models and determined that the best explanation for the amount of dust is a group of unseen asteroids that split the orbit of Venus.
We haven’t found those asteroids yet, so the hypothesis is far from confirmed. Who knows, maybe Parker will notice them; or maybe the probe will lead us to another explanation for the phenomenon. Either way, it will be interesting.
“We’re learning things about the dynamics, the exchange of dust particles in the heliosphere that we didn’t know before the Parker Solar Probe,” Stenborg said.
The research was published in The astrophysics journal.