SpaceX, founded by Elon Musk, recently launched the world's largest operational rocket on February 6.

Falcon Heavy's launch sent Musk's personal 2008 red Tesla Roadster on a voyage toward Mars orbit with a "Starman" dummy in the driver's seat.

Planetary scientists are concerned about bacterial contamination on Musk's car in case it crashes into Mars — a planet that may host alien microbes.

However, new calculations show the Tesla will most likely hit Earth, Venus, or the sun.



On February 6, SpaceX launched the world's most powerful operational rocket, called Falcon Heavy, for the first time.

The launch sent company founder Elon Musk's own red Tesla Roadster on a path that crosses the orbit of Mars. This attracted the attention of researchers worried about an eventual crash into the red planet, which would contaminate the world — and any alien microbes living there.

But planetary science researchers can now breathe a little easier, if a new study about the Roadster's fate is correct.

Musk put his Roadster on top of the 230-foot-tall rocket with a spacesuit-clad dummy named "Starman" in the driver's seat. Launching the car demonstrated Falcon Heavy's capabilities and was reportedly a backup plan for a scientific NASA or military payload.

The Roadster's short-lived yet unparalleled camera feeds, overall silliness (as Musk has described it), and far-flung path through space captured global attention.

But not all of it has proved welcome.

SpaceX founder Elon Musk in a press conference after the launch of Falcon Heavy. Dave Mosher/Business Insider The Planetary Society's Jason Davis bemoaned the planetary protection risk posed by Musk's un-sterilized car crashing into Mars and sprinkling debris coated with bacteria, viruses, and fungi all over the planet. The reason: alien microbes may be hiding out in Martian soil.

"NASA goes to great lengths sterilizing spacecraft designed to land on Mars, in order to make sure there's no chance of Earthly microbes contaminating the surface," Davis wrote in a post before launch. "Such a contamination could harm existing life and muddle scientific efforts to search for said life."

But that risk now appears minimal, according to a new scientific study titled "The random walk of cars and their collision probabilities with planets."

Three researchers at the University of Toronto posted their paper on Tuesday to the pre-print arXiv server and submitted to the Monthly Notices of the Royal Astronomical Society.

Where and when Musk's Tesla will most likely crash

A chart showing the location of Elon Musk's Tesla Roadster in space on February 15, 2018. WhereIsTesla.com

Hanno Rein, an astrophysicist and lead author of the study, said the roughly week-long research came out of advanced orbital-mechanics computer simulations.

"Earth is the most likely place the car will crash, followed by Venus, and then the sun," Rein told Business Insider, and likely within 10 million years — not hundreds of millions or possibly billions, as Musk has suggested.

To arrive at that conclusion, Rein and his colleagues started with orbital tracking data for the Roadster posted by NASA's Jet Propulsion Laboratory. Then they plugged that data into simulation software called REBOUND, which allowed them to fast-forward the car's likeliest orbital paths through the solar system over the next few million years.

That data suggest Musk's car will fly out past Mars orbit, spending very little time there, and then swing back around, over and over again.

"Every 30 years or so, it will come relatively close to the Earth," Rein said, where it will get a gravitational tug. "This causes a change of a few percent in some of the orbital parameters. The distance to the sun would change slightly, for example, and the orbit's eccentricity."

The calculations suggest the Roadster will come within one Earth-moon distance of our planet within 100 years, possibly enabling new Earth-based telescope views.

Elon Musk's red Tesla Roadster before launching on a Falcon Heavy rocket toward Mars orbit. Elon Musk/SpaceX; Instagram

But after its third flyby, Rein said the Roadster will take on an increasingly chaotic and somewhat unpredictable path through space. That's because those gravitational tugs near Earth's orbit — where the car will spend most of its time compared to other bodies in the system — can "lead to a huge change afterward," Rein said.

By running hundreds of different simulations of those orbital possibilities out to 3.5 million years from today, Rein and his colleagues figured out there's a 6% chance of the Roadster crashing into Earth and a 2.5% chance of crashing into Venus during that time.

"We've not seen any single collision with Mars in 240 simulations, though we continue to run them and see what happens," Rein said. "The likely outcome is that it will crash, in tens of millions of years, into Earth or Venus or the sun."

Astronomers are tracking the car in space

Two other astronomers — Gianluca Masi of The Virtual Telescope Project and Michael Schwartz of Tenagra Observatories, Ltd. — also used JPL data to track the Roadster.

Last week, they managed to photograph the car flying beyond the moon moving at a speed of roughly 25,000 miles per hour.

The vehicle is reflective enough to see through a telescope, at least for now, leading to what they called a "stunning" animation of several images.



Masi said he and Schwartz will continue to track the Roadster for as long as possible.

"The object is slowly fading: you can image it now with a 6" or so scope," Masi told Business Insider in an email. "In one month or so it will need a much larger scope to be imaged (16" or larger)."