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'How did we get here?' NASA hopes 'artificial star' can teach us more about the universe

2024-12-27 13:02:40 Stocks
  • Once in orbit, the so-called "artificial star" will be far enough away to look like a star to telescopes back on Earth.
  • The satellite will then begin the work of helping researchers study star brightness to gain more precise estimates of their size, scale and age.
  • By doing so, the researchers hope to uncover fresh clues about how fast the universe is expanding and, just maybe, whether life could exist anywhere else in the universe.

Look up into the sky on a clear night, and you're likely to glimpse thousands of stars dotting the cosmos. Add a telescope into the mix, and suddenly millions more come into view.

The Milky Way is brimming with an estimated hundred billions stars, giant balls of hot gas, including our galaxy's most famous – the sun. But outside of our home galaxy? The number of stars is near unfathomable.

Yet getting a handle on observing stars, which form in large molecular clouds of gas and dust, is crucial to better understand not only how they evolve, but how our universe grows and changes with them, astronomers say.

To do that, what's the harm of adding just one more "star" to the mix – even if it's a humanmade one?

In a $19.5 million NASA-funded mission, researchers at George Mason University are heading a project to construct and eventually launch a small satellite into space. Once in orbit, the contraption will be far enough away to look like a star to telescopes back on Earth.

The satellite will then begin the work of helping researchers study star brightness to gain more precise estimates of their size, scale and age. By doing so, the researchers hope to uncover fresh clues about how fast the universe is expanding and, just maybe, whether life could exist anywhere else in the universe.

“It might impact and change the way we measure or understand the properties of stars, surface temperatures and the habitability of exoplanets," said Eliad Peretz of NASA's Goddard Space Flight Center, who is the mission's deputy principal investigator.

Here's a look inside NASA's plan to launch an "artificial star" over the U.S. before the end of the decade.

Artificial star will be visible to ground telescopes

The purpose of the so-named Landolt NASA Space Mission is to place a calibrated light source into orbit at a distance of 22,236 miles from the Earth.

The satellite, or "artificial star," that the astronomers shoot into orbit won't be big enough, bright enough or close enough for skygazers to detect with the naked eye, but it should be visible to anyone with a telescope. Named for late astronomer Arlo Landolt, who created a renowned star catalog, the satellite will then spend its inaugural year in space moving at the same speed as Earth's rotation, keeping it positioned over the United States.

In technical terms, the small satellite is what's called a CubeSat, which is a a class of nanosatellites. Equipping the device with a cache of eight lasers will allow it to provide consistent observations on brightness levels of millions of stars to mission control on George Mason's campus in Fairfax, Virginia and other observatories.

By providing data that ground-based telescopes cannot, the artificial star should be able to refine the accuracy of measuring stellar brightness levels of nearby stars and even distant supernovae in far-away galaxies, Peter Plavchan, an astronomer at George Mason University, explained in a paper on the project.

"The Landolt mission will allow us to re-calibrate the brightnesses of millions of stars," Plavchan, the mission's primary investigator, wrote. "Such measurements can only be achieved by a space-based orbiting artificial star."

George Mason leading $19.5 million Landolt NASA Space Mission

NASA, which recently approved the mission for deployment as part of the space agency's Pioneers program, is providing the funding.

While $19.5 million is relatively low-cost in terms of space missions, the green light represents a major first for George Mason, which will build and operate the mission for NASA.

But the university won't be doing it alone.

Along with NASA, George Mason will also partner with the National Institute of Standards and Technology – a U.S. Department of Commerce agency – as well as 10 other universities to develop the satellite.

“This is an incredibly exciting opportunity for George Mason and our students," said Peter Pachowicz, an engineering associate professor at George Mason who is part of the Landolt mission, in a statement. "Our team will design, build, and integrate the payload, which, because it’s going very high into geostationary orbit, must handle incredible challenges.”

NASA will provide management and oversight of Landolt, which is already part of the space agency's fleet chart, by hosting reviews in the coming years amid key decision points, Plavchan told USA TODAY. He added that he and other mission operators will also provide monthly briefings to NASA.

A specific launch vehicle will not be selected for another two-and-a-half years, Plavchan said. And because the Landolt satellite will be relatively small, the craft will have to hitch a ride to orbit via a private space company with the launch of either a bigger satellite or a set of small satellites, he added.

Understanding more about habitable planets

The Landolt mission is not just one of a characterizing the brightness of stars. As the satellite gazes into the endless expanse of outer space, astronomers hope to learn about distant terrestrial worlds that could harbor life.

Astronomers have long been interested in so-called habitable zones and the abundance of ocean worlds theorized to exist throughout the cosmos. Next month, NASA is on the cusp of launching its own largest planetary craft to date to study Jupiter's moon Europa to see if the vast ocean beneath its surface hold clues to how life could exist beyond our own planet.

By gathering data on stellar evolution, the Landolt mission may play a vital role in helping identify habitable zones where planets could have water, providing a key ingredient for life to flourish. In a nod to the classic fairy tale, astronomers even refer to these regions as "Goldilocks" zones because conditions have to be just right – neither too hot nor too cold – for water to remain in liquid form and pool on planetary surfaces.

While finding evidence of life on another planet would be monumental, it's a tricky business: One that requires diligence and an abundance of evidence to determine, for instance, if a star gives off enough energy or if a planet is close enough to support life, explained Jamie Tayar, an astronomer at the University of Florida, a partner on the Landolt mission.

“There are so many big questions in astronomy: How did we get here? Are there other planets like ours? Do aliens exist?” Tayar said in a statement. “But those are really hard questions, and so to answer them the measurements have to be really good, and they have to be right.”

The team hopes to launch the "artificial star" into orbit by 2029.

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]

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