More Details Emerge About 'Oumuamua, Earth's First-Recorded Interstellar Visitor

 NASA/JPL-Caltech
NASA/JPL-Caltech

In October, scientists using the University of Hawaii's Pan-STARRS 1 telescope sighted something extraordinary: Earth's first confirmed interstellar visitor. Originally called A/2017 U1, the once-mysterious object has a new name—'Oumuamua, according to Scientific American—and researchers continue to learn more about its physical properties. Now, a team from the University of Hawaii's Institute of Astronomy has published a detailed report of what they know so far in Nature.

Fittingly, "'Oumuamua" is Hawaiian for "a messenger from afar arriving first." 'Oumuamua's astronomical designation is 1I/2017 U1. The "I" in 1I/2017 stands for "interstellar." Until now, objects similar to 'Oumuamua were always given "C" and "A" names, which stand for either comet or asteroid. New observations have researchers concluding that 'Oumuamua is unusual for more than its far-flung origins.

It's a cigar-shaped object 10 times longer than it is wide, stretching to a half-mile long. It's also reddish in color, and is similar in some ways to some asteroids in our solar system, the BBC reports. But it's much faster, zipping through our system, and has a totally different orbit from any of those objects.

After initial indecision about whether the object was a comet or an asteroid, the researchers now believe it's an asteroid. Long ago, it might have hurtled from an unknown star system into our own.

'Oumuamua may provide astronomers with new insights into how stars and planets form. The 750,000 asteroids we know of are leftovers from the formation of our solar system, trapped by the Sun's gravity. But what if, billions of years ago, other objects escaped? 'Oumuamua shows us that it's possible; perhaps there are bits and pieces from the early years of our solar system currently visiting other stars.

The researchers say it's surprising that 'Oumuamua is an asteroid instead of a comet, given that in the Oort Cloud—an icy bubble of debris thought to surround our solar system—comets are predicted to outnumber asteroids 200 to 1 and perhaps even as high as 10,000 to 1. If our own solar system is any indication, it's more likely that a comet would take off before an asteroid would.

So where did 'Oumuamua come from? That's still unknown. It's possible it could've been bumped into our realm by a close encounter with a planet—either a smaller, nearby one, or a larger, farther one. If that's the case, the planet remains to be discovered. They believe it's more likely that 'Oumuamua was ejected from a young stellar system, location unknown. And yet, they write, "the possibility that 'Oumuamua has been orbiting the galaxy for billions of years cannot be ruled out."

As for where it's headed, The Atlantic's Marina Koren notes, "It will pass the orbit of Jupiter next May, then Neptune in 2022, and Pluto in 2024. By 2025, it will coast beyond the outer edge of the Kuiper Belt, a field of icy and rocky objects."

Last month, University of Wisconsin–Madison astronomer Ralf Kotulla and scientists from UCLA and the National Optical Astronomy Observatory (NOAO) used the WIYN Telescope on Kitt Peak, Arizona, to take some of the first pictures of 'Oumuamua. You can check them out below.

Images of an interloper from beyond the solar system — an asteroid or a comet — were captured on Oct. 27 by the 3.5-meter WIYN Telescope on Kitt Peak, Ariz.
Images of 'Oumuamua—an asteroid or a comet—were captured on October 27.
WIYN OBSERVATORY/RALF KOTULLA

U1 spotted whizzing through the Solar System in images taken with the WIYN telescope. The faint streaks are background stars. The green circles highlight the position of U1 in each image. In these images U1 is about 10 million times fainter than the faint
The green circles highlight the position of U1 in each image against faint streaks of background stars. In these images, U1 is about 10 million times fainter than the faintest visible stars.
R. Kotulla (University of Wisconsin) & WIYN/NOAO/AURA/NSF

Color image of U1, compiled from observations taken through filters centered at 4750A, 6250A, and 7500A.
Color image of U1.
R. Kotulla (University of Wisconsin) & WIYN/NOAO/AURA/NSF

Editor's note: This story has been updated.

Stardust Created 7 Billion Years Ago Is the Oldest Stuff on Earth

NASA/JPL-Caltech/Harvard-Smithsonian CfA
NASA/JPL-Caltech/Harvard-Smithsonian CfA

Between 5 and 7 billion years ago, a dying star shot an explosion of particles through space. Some of that stardust ended up in a meteorite that landed in Murchison, Australia, in 1969. And according to new research, it's officially the oldest known solid material on Earth.

For the new study, published in the journal Proceedings of the National Academy of Sciences 30 years after the research began, scientists pulverized fragments of the meteorite to determine its age. The resulting paste-like substance reportedly smelled like "rotten peanut butter." The strange aroma "comes from byproducts of the breakdown of the abiotic organic molecules—molecules that didn't form from life—in the Murchison meteorite," lead author Philipp R. Heck, a curator at Chicago's Field Museum, tells Mental Floss.

Heck used acid to further break down the rock and isolate the grains of stardust, which are smaller than the period at the end of this sentence. To date the particles, the team measured neon isotopes that formed when cosmic rays hit the solid matter making up the stardust. The older the stardust is, the more cosmic rays it has been exposed to, so the amount of neon isotopes it contains can be used to estimate its age. Heck compares the method to collecting water in a bucket to determine how long it's been raining.

The team found that the meteorite contained particles older than 5.5 billion years and possibly as old as 7 billion years. The Earth has only been around for 4.5 billion years, and the sun for 4.6 billion. The formation of this super-old stardust is believed to have occurred during an "astral baby boom," according to a statement released by the Field Museum, in which an uptick in stellar activity literally created the matter that shapes the world we know today.

When the grains formed, "most stars that we see tonight in the sky didn’t exist," Heck says. "The bright stars that would have been shining through our galaxy were the previous generation of stars, our parent stars. [They] formed the elements that later became fuel and ingredients for the solar system, Earth, and us. These stars formed the material that we are made out of."

While the grains in the Murchison meteorite are the oldest solid material on the planet, many of the gases on Earth are much older. Some of the hydrogen in your body, for example, may have originated with the Big Bang 13.7 billion years ago.

17-Year-Old NASA Intern Helped Discover Twin-Starred 'Tatooine' Planet

NASA's Goddard Space Flight Center/Chris Smith
NASA's Goddard Space Flight Center/Chris Smith

On January 6, NASA announced that it had detected an Earth-sized planet, TOI 700 d, 100 light-years away from Earth that could be capable of hosting life. The same mission also led to the discovery of a rare planet with twin suns courtesy of a 17-year-old intern.

As CNN reports, high school student Wolf Cukier was combing through data collected by NASA's Transiting Exoplanet Survey Satellite, or TESS, when he noticed something strange about one binary star system. The system TOI 1338 consists of two stars that orbit each other once every 15 days. When the smaller of the two stars passes across the larger one, it's known as a stellar eclipse. But one signal that had been flagged as a stellar eclipse wasn't an eclipse at all; just three days into his internship at NASA's Goddard Space Flight Center, Cukier had found a planet orbiting the two stars.

The planet, since dubbed TOI 1338 b, is like a real-life version of Luke Skywalker's home planet Tatooine from the Star Wars movies. It's located roughly 1300 light-years away in the Pictor constellation and is somewhere between Neptune and Saturn in size. Twin-starred planets are rare, and this marks this first one detected through NASA's planet-hunting TESS mission.

TESS launched in 2018 with the goal of finding new planets outside our own solar system. Planets are typically discovered by recording stars over time and looking for dips in their brightness that indicate passing planets. This system becomes complicated when dealing with binary star systems, as dips in light caused by a planet in transit can get confused with an eclipsing star and vice versa. Without Cukier's keen eye, this latest discovery may have gone undetected.

It may have the same number of stars as Tatooine, but the similarities TOI 1338 b shares with the planet from Star Wars end there. So far, TOI 700 d is the only planet discovered by TESS that has a chance of being habitable.

[h/t CNN]

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