It’s not aliens, and it is not a newly-found celestial body, but nonetheless, the discovery is of great importance since most of the discoveries in the inner solar system have long been made.
Two new studies report the discovery of previously unseen dust rings in the inner solar system: one in the orbit of Mercury and another asteroid ring in the orbit where Venus ‘circles’ the sun.
“It’s not every day you get to discover something new in the inner solar system,” explains Marc Kuchner, an author on the Venus study and astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“This is right in our neighborhood.”
William Stenborg and Russell Howard, both solar scientists at the Naval Research Laboratory, describe their finding of “a fine mist of cosmic dust” in Mercury’s orbit in The Astrophysical Journal.
The recently discovered material forms a cosmic ring of approximately 14.9 million kilometers in length and 4.860 in width, large enough for the continental United States to extend through this vast track of dust as it surrounds the Sun.
Ironically, the two researchers stumbled upon the existence of the previously unseen ring as they searched for evidence of a dust-free region near the Sun.
At a distance from the Sun, according to a decades-old prediction, the strong heat of the star should vaporize the dust, sweeping away anything ‘small enough’, leaving behind empty space.
Knowing where this limit is can tell scientists about the composition of the dust itself, and hint at how planets formed in the young solar system.
However, it is noteworthy to mention that isn’t the first time that scientists have found a ring of dust in the inner solar system.
Twenty-five years ago, scientists discovered that the Earth orbits around the Sun in a gigantic ring of dust.
Others discovered a similar ring near the orbit of Venus, first using file data from the Helios space probes in 2007, whose existence was confirmed in 2013, with data from the STEREO mission.
Since then, scientists determined that the ring of dust in Earth’s orbit comes largely from the asteroid belt, the vast donut-shaped region between Mars and Jupiter, where most of the asteroids of the solar system reside.
These asteroids constantly collide with each other, producing dust that eventually goes deeper into the sun’s gravity, unless our planet’s gravity pulls the dust to one side, near the orbit of Earth.
“So far, no evidence has been found of dust-free space, but that’s partly because it would be difficult to detect from Earth.”
“No matter how scientists look from Earth, all the dust in between us and the Sun gets in the way, tricking them into thinking perhaps space near the Sun is dustier than it really is,” explained researchers.