Nav: Home

First interstellar immigrant discovered in the solar system

May 21, 2018

A new study has discovered the first known permanent immigrant to our Solar System. The asteroid, currently nestling in Jupiter's orbit, is the first known asteroid to have been captured from another star system. The work is published in Monthly Notices of the Royal Astronomical Society: Letters.

The object known as 'Oumuamua was the last interstellar interloper to hit the headlines in 2017. However it was just a tourist passing through, whereas this former exo-asteroid - given the catchy name (514107) 2015 BZ509 - is a long-term resident.

All of the planets in our Solar System, and the vast majority of other objects as well, travel around the Sun in the same direction. However 2015 BZ509 is different - it moves in the opposite direction in what is known as a 'retrograde' orbit.

"How the asteroid came to move in this way while sharing Jupiter's orbit has until now been a mystery," explains Dr Fathi Namouni, lead author of the study. "If 2015 BZ509 were a native of our system, it should have had the same original direction as all of the other planets and asteroids, inherited from the cloud of gas and dust that formed them."

However the team ran simulations to trace the location of 2015 BZ509 right back to the birth of our Solar System, 4.5 billion years ago when the era of planet formation ended. These show that 2015 BZ509 has always moved in this way, and so could not have been there originally and must have been captured from another system.

"Asteroid immigration from other star systems occurs because the Sun initially formed in a tightly-packed star cluster, where every star had its own system of planets and asteroids," comments Dr Helena Morais, the other member of the team.

"The close proximity of the stars, aided by the gravitational forces of the planets, help these systems attract, remove and capture asteroids from one another."

The discovery of the first permanent asteroid immigrant in the Solar System has important implications for the open problems of planet formation, solar system evolution, and possibly the origin of life itself.

Understanding exactly when and how 2015 BZ509 settled in the Solar System provides clues about the Sun's original star nursery, and about the potential enrichment of our early environment with components necessary for the appearance of life on Earth.
-end-


Royal Astronomical Society

Related Solar System Articles:

Pressure runs high at edge of solar system
Out at the boundary of our solar system, pressure runs high.
What a dying star's ashes tell us about the birth of our solar system
A UA-led team of researchers discovered a dust grain forged in a stellar explosion before our solar system was born.
What scientists found after sifting through dust in the solar system
Two recent studies report discoveries of dust rings in the inner solar system: a dust ring at Mercury's orbit, and a group of never-before-detected asteroids co-orbiting with Venus, supplying the dust in Venus' orbit.
Discovered: The most-distant solar system object ever observed
A team of astronomers has discovered the most-distant body ever observed in our solar system.
Discovery of the first body in the Solar System with an extrasolar origin
Asteroid 2015 BZ509 is the very first object in the Solar System shown to have an extrasolar origin.
First interstellar immigrant discovered in the solar system
A new study has discovered the first known permanent immigrant to our solar system.
A star disturbed the comets of the solar system in prehistory
About 70,000 years ago, when the human species was already on Earth, a small reddish star approached our solar system and gravitationally disturbed comets and asteroids.
Scientists detect comets outside our solar system
Scientists from MIT and other institutions, working closely with amateur astronomers, have spotted the dusty tails of six exocomets -- comets outside our solar system -- orbiting a faint star 800 light years from Earth.
Does the organic material of comets predate our solar system?
The Rosetta space probe discovered a large amount of organic material in the nucleus of comet 'Chury.' In an article published by MNRAS on Aug.
Tracking a solar eruption through the solar system
Ten spacecraft, from ESA's Venus Express to NASA's Voyager-2, felt the effect of a solar eruption as it washed through the solar system while three other satellites watched, providing a unique perspective on this space weather event.
More Solar System News and Solar System Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Risk
Why do we revere risk-takers, even when their actions terrify us? Why are some better at taking risks than others? This hour, TED speakers explore the alluring, dangerous, and calculated sides of risk. Guests include professional rock climber Alex Honnold, economist Mariana Mazzucato, psychology researcher Kashfia Rahman, structural engineer and bridge designer Ian Firth, and risk intelligence expert Dylan Evans.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.