We Are “Extragalactic Immigrants” from Faraway Galaxies, Discover Astrophysicists

Northwestern University researchers discover the unexpected origins of half the atoms in our bodies.

We Are “Extragalactic Immigrants” from Faraway Galaxies, Discover Astrophysicists
credit: Pixabay


Not only are we made of stardust, but we may come from a galaxy far, far away. Astrophysicists discovered that up to half of the matter in our Milky Way galaxy comes from other, distant galaxies.

The scientists used supercomputer simulations to make the surprising discovery that galaxies get matter through intergalactic transfer. Supernova explosions within one galaxy eject so much gas that it gets picked up by galactic winds that transport it to other galaxies. That way atoms get moved from one part of the cosmos to another. 

“Given how much of the matter out of which we formed may have come from other galaxies, we could consider ourselves space travelers or extragalactic immigrants,” said Daniel Anglés-Alcázar, a postdoctoral fellow at Northwestern who led the study.  

He added that it’s likely a large amount of the matter in the Milky Way came from other galaxies after it got “kicked out by a powerful wind, traveled across intergalactic space and eventually found its new home in the Milky Way.”

This would have taken several billion years to accomplish, even if galactic winds can move at several hundred kilometers per second. 

Check out this animation illustrating the intergalactic transfer of gas:

Anglés-Alcázar developed advanced algorithms that mined the data generated by researchers from the FIRE (“Feedback in Realistic Environments”) project, led by Northwestern professor Claude-André Faucher-Giguère. The FIRE team created numerical simulations that resulted in realistic 3-D models of galaxies, from the Big Bang to the present. The algorithm by Anglés-Alcázar was able to quantify how the matter was transferred between the galaxies. 

“This study transforms our understanding of how galaxies formed from the Big Bang,” explained Faucher-Giguère, a co-author of the study. “What this new mode implies is that up to one-half of the atoms around us — including in the solar system, on Earth and in each one of us — comes not from our own galaxy but from other galaxies, up to one million light years away.”

The team was able to track how gas from smaller galaxies ends up in the larger ones, like our Milky Way, where the gas forms stars. 

“Our origins are much less local than we previously thought,” pointed out Faucher-Giguère. “This study gives us a sense of how things around us are connected to distant objects in the sky.” 

The findings provide unique insights into how galaxies grow. The scientists plan to test their results by collaborating with observational astronomers working on the Hubble Space Telescope and ground-based observatories.

Check out the study “The Cosmic Baryon Cycle and Galaxy Mass Assembly in the FIRE Simulations” here. It is published by the Monthly Notices of the Royal Astronomical Society.

What does kindness look like? It wears a mask.

Northwell Health CEO Michael Dowling has an important favor to ask of the American people.

Sponsored by Northwell Health
  • Michael Dowling is president and CEO of Northwell Health, the largest health care system in New York state. In this PSA, speaking as someone whose company has seen more COVID-19 patients than any other in the country, Dowling implores Americans to wear masks—not only for their own health, but for the health of those around them.
  • The CDC reports that there have been close to 7.9 million cases of coronavirus reported in the United States since January. Around 216,000 people have died from the virus so far with hundreds more added to the tally every day. Several labs around the world are working on solutions, but there is currently no vaccine for COVID-19.
  • The most basic thing that everyone can do to help slow the spread is to practice social distancing, wash your hands, and to wear a mask. The CDC recommends that everyone ages two and up wear a mask that is two or more layers of material and that covers the nose, mouth, and chin. Gaiters and face shields have been shown to be less effective at blocking droplets. Homemade face coverings are acceptable, but wearers should make sure they are constructed out of the proper materials and that they are washed between uses. Wearing a mask is the most important thing you can do to save lives in your community.
Keep reading Show less

Science confirms: Earth has more than one 'moon'

Two massive clouds of dust in orbit around the Earth have been discussed for years and finally proven to exist.

J. Sliz-Balogh, A. Barta and G. Horvath
Surprising Science
  • Hungarian astronomers have proven the existence of two "pseudo-satellites" in orbit around the earth.
  • These dust clouds were first discovered in the sixties, but are so difficult to spot that scientists have debated their existence since then.
  • The findings may be used to decide where to put satellites in the future and will have to be considered when interplanetary space missions are undertaken.
Keep reading Show less

Scientists stumble across new organs in the human head

New cancer-scanning technology reveals a previously unknown detail of human anatomy.

Credit: Valstar et al., Netherlands Cancer Institute
Surprising Science
  • Scientists using new scanning technology and hunting for prostate tumors get a surprise.
  • Behind the nasopharynx is a set of salivary glands that no one knew about.
  • Finding the glands may allow for more complication-free radiation therapies.
Keep reading Show less

Millennials reconsidering finances and future under COVID-19

A new survey found that 27 percent of millennials are saving more money due to the pandemic, but most can't stay within their budgets.

Personal Growth
  • Millennials have been labeled the "unluckiest generation in U.S. history" after the one-two financial punch of the Great Recession and the pandemic shutdowns.
  • A recent survey found that about a third of millennials felt financially unprepared for the pandemic and have begun saving.
  • To achieve financial freedom, millennials will need to take control of their finances and reinterpret their relationship with the economy.
  • Keep reading Show less
    Personal Growth

    6 easy ways to transition to a plant-based diet

    Your health and the health of the planet are not indistinguishable.

    Scroll down to load more…
    Quantcast