Huge asteroid ‘following’ Mars could be long-lost ‘STOLEN’ twin of Earth’s Moon
A HUGE asteroid that's following Mars's orbit could be our Moon's 'long-lost twin'.
This is according scientists who say the space rock has an identical composition to some parts of the lunar surface.
The researchers think asteroid could have ancient origins closers to home.
They said it could be a "relic fragment of the Moon's original solid crust".
Scientists used a tool called a spectrograph on the European Southern Observatory's 8-m Very Large Telescope (VLT) in Chile to observe the asteroid.
It allowed them to see how sunlight reflected from it and then they compared it to the Moon.
Armagh Observatory and Planetarium astrochemist Galin Borisov explained: "The spectrum of this particular asteroid seems to be almost a dead-ringer for parts of the Moon where there is exposed bedrock such as crater interiors and mountains.";
We don't know for sure why that is but one theory is that the Moon and the asteroid have a similar origin or were once combined and then broke apart.
AOP astronomer Apostolos Christou said: "The early Solar System was very different from the place we see today.
"The space between the newly-formed planets was full of debris and collisions were commonplace.
"Large asteroids [planetesimals] were constantly hitting the Moon and the other planets.
"A shard from such a collision could have reached the orbit of Mars when the planet was still forming and was trapped in its Trojan clouds."
There are said to be other explanations for the similarities though and the asteroid could even be a fragment of Mars itself.
Much more research is needed before we can be certain either way.
These findings have been reported online in the journal .
The Moon – our closest neighbour explained
Here's what you need to know...
- The Moon is a natural satellite – a space-faring body that orbits a planet
- It's Earth's only natural satellite, and is the fifth biggest in the Solar System
- The Moon measures 2,158 miles across, roughly 0.27 times the diameter of Earth
- Temperatures on the Moon range from minus 173 degrees Celcius to 260 degrees Celcius
- Experts assumed the Moon was another planet, until Nicolaus Copernicus outlined his theory about our Solar System in 1543
- It was eventually assigned to a "class" after Galileo discovered four moons orbiting Jupiter in 1610
- The Moon is believed to have formed around 4.51billion years ago
- The strength of its gravitational field is about a sixth of Earth's gravity
- Earth and the Moon have "synchronous rotation", which means we always see the same side of the Moon – hence the phrase "dark side of the Moon"
- The Moon's surface is actually dark, but appears bright in the sky due to its reflective ground
- During a solar eclipse, the Moon covers the Sun almost completely. Both objects appear a similar size in the sky because the Sun is both 400 times larger and farther
- The first spacecraft to reach the Moon was in 1959, as part of the Soviet Union's Lunar program
- The first manned orbital mission was Nasa's Apollo 8 in 1968
- And the first manned lunar landing was in 1969, as part of the Apollo 11 mission
Most read in Science
In other news, a moon of Saturn may have the ideal conditions to support alien life, evidence suggests.
It's a good week to learn about all the planets in our Solar System as an impressive six will be visible in the night sky.
And, a huge asteroid nicknamed the 'God of Chaos' is gaining speed as it travels towards Earth.
What are your thoughts on the 'Moon twin' theory? Let us know in the comments...
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