Down on Earth around 3.5 million years ago, humanity was starting to take its earliest forms in some regions of Africa. At the same time, the sky was bursting with radiation from an explosive flare that took place in the center of the Milky Way.
An international team of astronomers recently found evidence of the explosion, the impact of which extended across 200,000 light-years and released a flash of energy that shone out into space through the two poles of our galaxy. And while humans probably couldnt see this flare, if there are any intelligent beings in the rest of the galaxy, they may have caught a glimpse.
The study, published on Sunday in The Astrophysical Journal, is based on observations made by the Hubble Space Telescope that caught the afterglow of the flare.
Gerald Cecil, Ph.D., professor of physics and astronomy at the University of North Carolina and co-author of the study, believes that the flare was caused by gas and shattered stars falling into the supermassive black hole at the center of the Milky Way.
We then see this glowing light, Cecil tells Inverse. Although we dont have a direct view of the explosion in the center, we see its reflective light.
The new study is based on a 2013 discovery of the Magellanic Stream, a stream of gas clouds that extends over the Milky Way, as shown in the video above. Light from distant quasars, massive and extremely bright cosmic objects, passed through the stream on its way to Earth. The composition of the arc, which removed some parts of the quasar light, led the team to suspect that something was heating and lighting up the gas stream.
What the team managed to observe was the fading remnant of the explosion, which was much brighter when it occurred 3.5 million years ago.
The fire is over, and were looking at the glowing coals, Cecil says. A lightbulb burning out.
The researchers estimate that the blast may have lasted for 300,000 years but is no longer active today based on mathematical models of how the heated gas de-energized.
The supermassive black hole in the Milky Way is always flickering, if an asteroid fell in instead of dust, you might get a flare that lasts for hours, Cecil says.
The new findings suggest that our galaxy is more active than we had initially thought it to be. The Milky Way is known to have some low level activity but, according to Cecil, this new research suggests that it was perhaps a million times more active only a few million years ago than what astronomers believed in the past.
Other galaxies have this behavior, Cecil says. It puts the Milky Way into the mainstream.
Considering that this event took place only a couple of million years ago, an insignificant amount of time in the life of a galaxy, means that it may be one of many such episodes that have occurred over the lifetime of the Milky Way.
If we start thinking about the cumulative effects of those radiation, we have to incorporate them in the models of whats going on in the Milky Way, Cecil says. That hasnt been done reliably.
The new study casts the Milky Way in a new, perhaps brighter, light, as well as the activity of the black hole at its center, if it is in fact the culprit behind this relatively recent explosion. The team behind the research hopes to get a better understanding of the duration of the flare, and whether it flared back up again during that period or continued to fade gradually.
Another aspect of the findings that Cecil points out is that this galactic event may have been observed by other inhabitants of the Milky Way, which he strongly believes exist, and essentially synchronized everybodys clock to a point of reference in the galaxys timescale.
Here is an event thats galaxy wide, for wherever they are in the galaxy, Cecil says. There was an event, one that everyone could see.
Abstract: There is compelling evidence for a highly energetic Seyfert explosion (105657 erg) that occurred in the Galactic Centre a few million years ago. The clearest indications are the x-ray/-ray 10 kpc bubbles identified by the Rosat and Fermi satellites. In an earlier paper, we suggested another manifestation of this nuclear activity, i.e. elevated H emission along a section of the Magellanic Stream due to a burst (or flare) of ionizing radiation from Sgr A*. We now provide further evidence for a powerful flare event: UV absorption line ratios (in particular CIV/CII, Si IV/Si II) observed by the Hubble Space Telescope reveal that some Stream clouds towards both galactic poles are highly ionized by a source capable of producing ionization energies up to at least 50 eV. We show how these are clouds caught in a beam of bipolar, radiative ionization cones from a Seyfert nucleus associated with Sgr A*. In our model, the biconic axis is tilted by about 15 from the South Galactic Pole with an opening angle of roughly 60. For the Stream at such large Galactic distances (D > 75 kpc), nuclear activity is a plausible explanation for all of the observed signatures: elevated H emission and H ionization fraction (xe > 0.5), enhanced CIV/CII and Si IV/Si II ratios, and high CIV and Si IV column densities. Wind-driven shock cones are ruled out because the Fermi bubbles lose their momentum and energy to the Galactic corona long before reaching the Stream. Our time-dependent Galactic ionization model (stellar populations, hot coronal gas, cloud-halo interaction) is too weak to explain the Streams ionization. Instead, the nuclear flare event must have had a radiative UV luminosity close to the Eddington limit (fE 0.1 1). Our time-dependent Seyfert flare models adequately explain the observations and indicate the Seyfert flare event took place To = 3.5 1 Myr ago. The timing estimates are consistent with the mechanical timescales needed to explain the x-ray/-ray bubbles in leptonic jet/wind models ( 2 8 Myr).
The rest is here:
Astronomer who saw Milky Way black hole flare thinks ancient aliens saw it - Inverse
- Astronomy clubs want to help you enjoy the eclipse safely - NPR - March 16th, 2024 [March 16th, 2024]
- You Can See a Rare, Bright Comet This Month. Will It Be Visible During the Solar Eclipse? - Smithsonian Magazine - March 16th, 2024 [March 16th, 2024]
- Solar Eclipse Path Map Shows States Where Sun Will Be Blocked Out - Newsweek - March 16th, 2024 [March 16th, 2024]
- Deep-space astronomy sensor peers into the heart of an atom - Space.com - March 16th, 2024 [March 16th, 2024]
- Physics and Astronomy Colloquium - Professor Paul Cassak; Department of Physics and Astronomy, West Virginia ... - The University of Iowa - March 16th, 2024 [March 16th, 2024]
- United Nations prioritizes discussion of Dark and Quiet Skies - Astrobites - March 16th, 2024 [March 16th, 2024]
- The burning acid behind ant stings was spotted around two stars - WAPT Jackson - March 16th, 2024 [March 16th, 2024]
- The oddities known as Centaurs may sprout their tales after jumping to new orbits - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pair of astronomy brothers to host eclipse viewing event - KAIT - March 16th, 2024 [March 16th, 2024]
- How to watch the solar eclipse online - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- How does a black hole get to the center of a galaxy, and does the galaxy revolve around it? - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The eclipse gives astronomy clubs an opportunity to shine - Voice Of Alexandria - March 16th, 2024 [March 16th, 2024]
- AI 'for all': How access to new models is advancing academic research, from astronomy to education - Source - Microsoft - March 16th, 2024 [March 16th, 2024]
- KU Department of Physics & Astronomy professor receives prestigious NSF award for black hole research - Salina Post - March 16th, 2024 [March 16th, 2024]
- Inspect impressive Mare Imbrium Astronomy Now - Astronomy Now Online - March 16th, 2024 [March 16th, 2024]
- The Sky This Week from March 15 to 22: A conjunction of Venus and Saturn - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pons-Brooks and M31 - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The slightly weird mathematical coincidence behind an eclipse - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 17 NGC 7714: Starburst after Galaxy Collision - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- How to Safely View the Eclipse National Radio Astronomy Observatory - National Radio Astronomy Observatory - March 16th, 2024 [March 16th, 2024]
- NOIRLab releases jaw-dropping images, video of remnants from massive star explosion | Astronomy.com - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- JWST spots oceans' worth of water evaporating from a distant disk - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Radiation is vaporizing a young star's disk in the Orion Nebula - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 12 A Galaxy Shaped Rocket Exhaust Spiral - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- Best laptops for astronomers and astrophotographers in 2024 - Space.com - March 16th, 2024 [March 16th, 2024]
- Why astronomers are worried about 2 major telescopes right now - Space.com - March 16th, 2024 [March 16th, 2024]
- The People Behind Webb | Webb - WebbTelescope.org - March 16th, 2024 [March 16th, 2024]
- X-ray image of universe reveals almost 1 million high-energy objects: 'These are mind-blowing numbers' - Space.com - February 1st, 2024 [February 1st, 2024]
- Galaxy named 'Nube' is almost invisible, baffling astronomers Earth.com - Earth.com - February 1st, 2024 [February 1st, 2024]
- Giant Star Seen 150 Days Before it Exploded as a Supernova - Universe Today - February 1st, 2024 [February 1st, 2024]
- UH astronomer named to prominent national astronomical society | University of Hawaii System News - University of Hawaii - February 1st, 2024 [February 1st, 2024]
- The Art of SeeingStates of Astronomy - Announcements - E-Flux - February 1st, 2024 [February 1st, 2024]
- Pluto isn't really a planet, but it might be Arizona's official state planet - Arizona Mirror - February 1st, 2024 [February 1st, 2024]
- Did You Know? Stars Near and Far Reveal Their Secrets to CSUN Scientists - California State University, Northridge - February 1st, 2024 [February 1st, 2024]
- Top 10 space stories of 2023 - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- How we found the Milky Way's bar: This Week in Astronomy with Dave Eicher - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The best telescope to use with a smartphone - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- JWST releases 19 awe-inspiring images of spiral galaxies - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- Learning Shines Brightly at SuperKnova National Radio Astronomy Observatory - National Radio Astronomy Observatory - February 1st, 2024 [February 1st, 2024]
- The Crafoord Prize 2024 goes to three ERC grantees for their pioneering contributions to astronomy and mathematics ... - European Research Council - February 1st, 2024 [February 1st, 2024]
- The Moon's south pole is likely not the safest place for manned missions - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The moon could be perfect for cutting-edge telescopes but not if we don't protect it - Space.com - February 1st, 2024 [February 1st, 2024]
- February Astronomy: Spot the Milky Way and the Zodiacal Light While the Skies Are Darkest - Coachella Valley Independent - February 1st, 2024 [February 1st, 2024]
- You can stream an asteroid whizzing past Earth this weekend - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- Chinese Astronomy at the Royal Observatory | Royal Observatory | Things to do in London - Time Out London - February 1st, 2024 [February 1st, 2024]
- Astronomers in Chile to scour universe with car-sized mega camera - - February 1st, 2024 [February 1st, 2024]
- Dark Matter Might Help Explain How Supermassive Black Holes Can Merge - Universe Today - February 1st, 2024 [February 1st, 2024]
- How far away is the sun? They went on a perilous journey to find out. - National Geographic - February 1st, 2024 [February 1st, 2024]
- Scientists spotted an asteroid hours before it burned up over Germany - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- XRISM Unveils the Invisible: A New Era in X-Ray Astronomy - SciTechDaily - January 10th, 2024 [January 10th, 2024]
- New Astronomy Finding Uncovers the Mystery of Star Formation at the Edge of Galaxies - SBU News - Stony Brook News - January 10th, 2024 [January 10th, 2024]
- The Future Of Astronomy Lies In Artificial Intelligence - Forbes - January 10th, 2024 [January 10th, 2024]
- The 'Super Bowl of Astronomy' begins next week in New Orleans - Space.com - January 10th, 2024 [January 10th, 2024]
- Scientific American proposes policing the language of astronomy to make it beautiful and elegant, as well as ... - Why Evolution Is True - January 10th, 2024 [January 10th, 2024]
- 'Blob-like' home of farthest-known fast radio burst is collection of seven galaxies - Northwestern Now - January 10th, 2024 [January 10th, 2024]
- Astronomers revealed mysterious star formation by hearts of molecular clouds - Tech Explorist - January 10th, 2024 [January 10th, 2024]
- Spectroscopic sizing of interstellar icy grains with JWST - Nature.com - January 10th, 2024 [January 10th, 2024]
- Kip Thorne and the mind-bending science of Interstellar | Astronomy.com - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Here There Be DRAGNs National Radio Astronomy Observatory - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Unistellar's latest smart telescopes take the hassle out of backyard astronomy - Engadget - January 10th, 2024 [January 10th, 2024]
- 20 of the best places to view the 2024 total solar eclipse - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Northern Arizona astronomy: How old is our third generation sun? - Grand Canyon News - January 10th, 2024 [January 10th, 2024]
- Evidence builds that Kamo'oalewa is a chunk of the Moon accompanying Earth - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- The Sky This Week from January 5 to 12: Visitors to the Scorpion - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- AAS 243 NRAO Press Announcement - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Your guide to the sky in 2024 - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- The best binoculars for astronomy in 2024 - Popular Science - January 10th, 2024 [January 10th, 2024]
- Are we visible to alien astronomers? This study makes the case - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Mystery of Star Formation Revealed by Hearts of Molecular Clouds - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Astronomers Solve the Mystery of Giant Radio Circles - AZoQuantum - January 10th, 2024 [January 10th, 2024]
- Early Evolution of Planetary Disk Structures Seen for the First Time - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- XRISM's Revolutionary Insights into X-Ray Astronomy - AZoQuantum - January 10th, 2024 [January 10th, 2024]
- Vatican's chief astronomer talks about stars, beauty, truth - Aleteia - January 10th, 2024 [January 10th, 2024]
- Explore the cosmos in EAC Payson Campus astronomy workshops - Payson Roundup - January 10th, 2024 [January 10th, 2024]
- Neptune is more of a greenish blue than is commonly depicted - NPR - January 10th, 2024 [January 10th, 2024]
- First Yale Gravitational Wave Symposium sparks research innovation | Department of Physics - Yale University - January 10th, 2024 [January 10th, 2024]
- The best expensive telescopes for those ready to splurge - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Dinosaurs and a touch of astronomy | Education | paysonroundup.com - Payson Roundup - January 10th, 2024 [January 10th, 2024]
- Astronomical Illusions: New Images Reveal What Neptune and Uranus Really Look Like - SciTechDaily - January 10th, 2024 [January 10th, 2024]
- Book Review: Things That Go Bump in the Universe, by C. Rene James - The New York Times - December 16th, 2023 [December 16th, 2023]