A distant asteroid has been observed trailing in the wake of Mars’ gravity in greater detail than ever before, and the close-up reveals a striking similarity – raising some interesting questions about the body’s ancient origins.
The asteroid in question, named (101429) 1998 VF31, is part of a group of Trojan asteroids that share the orbit of Mars.
Trojans are celestial bodies located in gravitational regions of space near other planets, and located 60 degrees in front and behind the planet.
Most of the Trojan asteroids we know of share the orbit of Jupiter, but other planets have them as well, including Mars and Earth as well.
What makes (101429) 1998 VF31 (hereinafter referred to as “101429”) interesting is that among the late Trojans on the Red Planet (those that follow behind Mars as it orbits around the Sun), 101429 appears to be unique.
Depiction of Mars and the Trojans; 101429 is the blue dot that rotates around L5. (AOP)
The rest of the group, called the L5 Martian Trojans, all belong to what is known as the Eureka family, which consists of the 5261 Eureka – the first discovery of the Mars Troy – and a group of small parts believed to have separated from the parent space rocks.
But the number 101429 is different, and in a new study led by astronomers from the Arma and Planetarium Observatory (AOP) in Northern Ireland, the researchers wanted to study the cause.
Using a spectrophotometer named X-SHOOTER on a Very Large Telescope (VLT) at the 8-meter-long European Southern Observatory in Chile, the team examined how sunlight was reflected by 101429 and its L5 relatives in the Eureka family. Only, it appears that 101429 and the Eureka clan are not relatives after all, as the analysis showed that 101429 shows a spectral match of a satellite closer to home.
“The spectrum of this particular asteroid appears to be almost dead sound of parts of the moon where there are exposed base rocks such as inner craters and mountains,” explains Galen Borisov, astronomer at AOP.
While we cannot yet ascertain why this is so, the researchers say it is plausible that these Martian Trojan origins began somewhere far from the Red Planet, where the number 101429 represents “part of the remnants of the moon’s original hard crust.”
If true, then how did the long-lost moon twin end up as a Trojan linked to Mars?
A spectral comparison of 101429 and the surface of the moon. (AOP)
“The early Solar System was very different from where we see it today,” explains the study’s lead author, astronomer Apostolos Christou.
“The space between newly formed planets was filled with debris and collisions were common. Large asteroids [planetesimals] It was constantly hitting the moon and other planets. A fragment from this collision could have reached the orbit of Mars when the planet was still forming and was trapped in Trojan clouds.
It’s a captivating idea, but researchers say it’s not the only explanation for 101429’s past. It is also possible, and perhaps most likely, that Troy represented instead a portion of Mars torn apart by a similar type of accident that affected the Red Planet; Or it could be just a familiar asteroid that, through the weathering processes of solar radiation, ended up looking like the moon.
Additional observations containing more powerful spectrometers could be able to shed more light on this issue of space ratios, as might a visit to a future spacecraft, the team says, “which, on the way to Trojans, could obtain spectra. On Mars or the Moon for direct comparison with the asteroid data. “
The results are reported in Icarus.
