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Humans have observed many wonders across the cosmos. Yet, much of our universe is still shrouded in mystery.

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Among those mysteries is the formation of our universe,

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which should have resulted in a balance of matter and its corresponding counterpart, antimatter.

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Much of that matter is thought to exist in the form of dark matter, which can't be directly observed.

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Much of the antimatter can't be found at all!

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Studying fundamental particles originating from sources up to billions of light years away

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may hold the key to understanding both the composition and history of our universe.

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Welcome to the world of particle physics currently being explored from low-Earth orbit

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by the Alpha Magnetic Spectrometer, AMS-02, installed on the International Space Station (ISS).

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Title - Finding the Invisible. A NASA ScienceCast.

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Planets, stars, interstellar gas, dust. What we're able to observe across the universe

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comprises less than 5 percent of the total content found throughout the universe.

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The other 95 percent is dark - dark matter as well as dark energy.

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Dark Matter doesn't interact with or produce light, as far as we know.

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It doesn't consist of normal matter, or matter that can be observed directly.

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So how do you improve understanding of something that can't be observed?

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One way is to look for evidence of its interactions.

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Kirt Costello, the ISS Program Chief Scientist at Johnson Space Center,

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explains how the giant magnet of AMS-02 is working to help scientists test and modify their theories.

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"Scientists are using AMS-02 to look at cosmic rays, charged particles that travel near the speed of light.

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AMS-02 categorizes each cosmic ray, looking at a high energy range

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to see whether that stellar phenomena that we can measure, can account for all of the cosmic rays we're seeing.

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But, if you see something in the spectra that doesn't fit, then this could be evidence of dark matter interactions."

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By studying cosmic rays scientists are also able to search for antimatter.

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The Big Bang theory of the universe's origin requires a 50/50 ratio of matter to antimatter,

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but to date the amount of antimatter found doesn't come close to matching the amount of matter known to exist.

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Costello says, "One of the goals of the mission is to detect antimatter

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and see if there are any large collections of it out there somewhere." 

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When particles pass through the strong magnetic field produced by AMS-02, their paths bend.

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Antimatter particles stand out, because their paths bend in the opposite direction compared to matter particles.

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The instrument searches for antimatter with a sensitivity three orders of magnitude greater than the original AMS,

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which flew in space in June of 1998 aboard the space shuttle Discovery.

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This could support the discovery of antimatter pools that were previously undetectable.

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A key factor in our ability to get the most out of AMS-02 is time.

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Originally expected to have a lifespan of three years, the instrument has continued to perform

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into its eighth year of operation aboard the orbiting laboratory.

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In late 2019 and early 2020, astronauts conducted a series of space walks

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to replace AMS-02's cooling pumps, which were failing.

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Extending the life of the instrument will provide scientists more time

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in their quest to unveil some of the universe's greatest mysteries.

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For more on scientific studies being done on and from the space station, go to www.nasa.gov/iss-science.

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For more information about the origins of the universe, visit science.nasa.gov.