Black Holes Archives

April 30, 2019April 30, 2019 by Evan Gough

Rapidly Spinning Black Hole is Spitting Out Blobs of Plasma

An artist's illustration of the black hole V404 Cygni. Image Credit: ICRAR.

Black holes, those beguiling singularities that sit on the precipice of the known and the unknown, keep surprising us with their behaviour. As organizations like the Event Horizon Telescope have made clear, there’s a lot we don’t know about the holes, and worse than that, we don’t even know how much we don’t know.

Now scientists have observed a new phenomenon that adds to the black hole mystique: a rapidly spinning black hole that ejects massive blobs of plasma.

April 23, 2019April 23, 2019 by Matt Williams

You Could Travel Through a Wormhole, but it’s Slower Than Going Through Space

Artist illustration of a spacecraft passing through a wormhole to a distant galaxy. Image credit: NASA.

Special Relativity. It’s been the bane of space explorers, futurists and science fiction authors since Albert Einstein first proposed it in 1905. For those of us who dream of humans one-day becoming an interstellar species, this scientific fact is like a wet blanket. Luckily, there are a few theoretical concepts that have been proposed that indicate that Faster-Than-Light (FTL) travel might still be possible someday.

A popular example is the idea of a wormhole: a speculative structure that links two distant points in space time that would enable interstellar space travel. Recently, a team of Ivy League scientists conducted a study that indicated how “traversable wormholes” could actually be a reality. The bad news is that their results indicate that these wormholes aren’t exactly shortcuts, and could be the cosmic equivalent of “taking the long way”!

April 6, 2019April 6, 2019 by Matt Williams

Now We Know That Dark Matter Isn’t Primordial Black Holes

The early universe. Credit: Tom Abel & Ralf Kaehler (KIPACSLAC)/ AMNH/NASA

For over fifty years, scientists have theorized that roughly 85% of matter in the Universe’s is made up of a mysterious, invisible mass. Since then, multiple observation campaigns have indirectly witnessed the effects that this “Dark Matter” has on the Universe. Unfortunately, all attempts to detect it so far have failed, leading scientists to propose some very interesting theories about its nature.

One such theory was offered by the late and great Stephen Hawking, who proposed that the majority of dark matter may actually be primordial black holes (PBH) smaller than a tenth of a millimeter in diameter. But after putting this theory through its most rigorous test to date, an international team of scientists led from the Kavli Institute for the Physics and Mathematics of the Universe (IPMU) has confirmed that it is not.

March 15, 2019March 15, 2019 by Evan Gough

This Star has been Kicked Out of the Milky Way. It Knows What It Did.

Researchers from the University of Michigan confirm that a runaway star was ejected from the Milky Way's disk rather than the galactic core. Image Credit: Kohei Hattori

Every once in a while, the Milky Way ejects a star. The evicted star is typically ejected from the chaotic area at the center of the galaxy, where our Super Massive Black Hole (SMBH) lives. But at least one of them was ejected from the comparatively calm galactic disk, a discovery that has astronomers rethinking this whole star ejection phenomenon.

March 13, 2019March 13, 2019 by Matt Williams

Using Black Holes to Conquer Space: The Halo Drive!

Close-up of star near a supermassive black hole (artist’s impression). Credit: ESA/Hubble, ESO, M. Kornmesser

The idea of one day traveling to another star system and seeing what is there has been the fevered dream of people long before the first rockets and astronauts were sent to space. But despite all the progress we have made since the beginning of the Space Age, interstellar travel remains just that – a fevered dream. While theoretical concepts have been proposed, the issues of cost, travel time and fuel remain highly problematic.

A lot of hopes currently hinge on the use of directed energy and lightsails to push tiny spacecrafts to relativistic speeds. But what if there was a way to make larger spacecraft fast enough to conduct interstellar voyages? According to Prof. David Kipping – the leader of Columbia University’s Cool Worlds lab – future spacecraft could rely on a Halo Drive, which uses the gravitational force of a black hole to reach incredible speeds.

March 6, 2019March 19, 2019 by Matt Williams

Gamma Ray Telescopes could Detect Starships Powered by Black Hole

Illustration of the supermassive black hole at the center of the Milky Way. Credit: NRAO/AUI/NSF — Illustration of the supermassive black hole at the center of the Milky Way. It's huge, with over 4 times the mass of the Sun. But ultramassive black holes are even more massive and can contain billions of solar masses. Image Credit: Credit: NRAO/AUI/NSF

In the course of looking for possible signs of Extra-Terrestrial Intelligence (ETI), scientists have had to do some really outside-of-the-box thinking. Since it is a foregone conclusion that many ETIs would be older and more technologically advanced than humanity, those engaged in the Search for Extra-Terrestrial Intelligence (SETI) have to consider what a more advanced species would be doing.

A particularly radical idea that has been suggested is that spacefaring civilizations could harness radiation emitted from black holes (Hawking radiation) to generate power. Building on this, Louis Crane – a mathematician from Kansas State University (KSU) – recently authored a study that suggests how surveys using gamma telescopes could find evidence of spacecraft powered by tiny artificial black holes.

January 14, 2019January 14, 2019 by Evan Gough

Astronomers See the Exact Moment a Supernova Turned into a Black Hole (or Neutron Star)

A look at The Cow (approximately 80 days after explosion) from the W.M. Keck Observatory in Maunakea, Hawaii. The Cow is nestled in the CGCG 137-068 galaxy, 200 million light years from Earth. Image Credit:Raffaella Margutti/Northwestern University

On June 17th 2018, the ATLAS (Asteroid Terrestrial-impact Last Alert System) survey’s twin telescopes spotted something extraordinarily bright in the sky. The source was 200 million light years away in the constellation Hercules. The object was given the name AT2018cow or “The Cow.” The Cow flared up quickly, and then just as quickly it was gone.

What was it?

December 6, 2018December 6, 2018 by Paul M. Sutter

Astronomers Count all the Photons in the Universe. Spoiler Alert: 4,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 Photons

The NASA/ESA Hubble Space Telescope offers this delightful view of the crowded stellar encampment called Messier 68, a spherical, star-filled region of space known as a globular cluster. Mutual gravitational attraction amongst a cluster’s hundreds of thousands or even millions of stars keeps stellar members in check, allowing globular clusters to hang together for many billions of years. Astronomers can measure the ages of globular clusters by looking at the light of their constituent stars. The chemical elements leave signatures in this light, and the starlight reveals that globular clusters' stars typically contain fewer heavy elements, such as carbon, oxygen and iron, than stars like the Sun. Since successive generations of stars gradually create these elements through nuclear fusion, stars having fewer of them are relics of earlier epochs in the Universe. Indeed, the stars in globular clusters rank among the oldest on record, dating back more than 10 billion years. More than 150 of these objects surround our Milky Way galaxy. On a galactic scale, globular clusters are indeed not all that big. In Messier 68's case, its constituent stars span a volume of space with a diameter of little more than a hundred light-years. The disc of the Milky Way, on the other hand, extends over some 100 000 light-years or more. Messier 68 is located about 33 000 light-years from Earth in the constellation Hydra (The Female Water Snake). French astronomer Charles Messier notched the object as the sixty-eighth entry in his famous catalogue in 1780. Hubble added Messier 68 to its own impressive list of cosmic targets in this image using the Wide Field Camera of Hubble’s Advanced Camera for Surveys. The image, which combines visible and infrared light, has a field of view of approximately 3.4 by 3.4 arcminutes. Credit: Hubble/NASA/ESA

Imagine yourself in a boat on a great ocean, the water stretching to the distant horizon, with the faintest hints of land just beyond that. It’s morning, just before dawn, and a dense fog has settled along the coast. As the chill grips you on your early watch, you catch out of the corner of your eye a lighthouse, feebly flickering through the fog.

And – yes – there! Another lighthouse, closer, its light a little stronger. As you scan the horizon more lighthouses signal the dangers of the distant coast.
Continue reading “Astronomers Count all the Photons in the Universe. Spoiler Alert: 4,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 Photons”

October 23, 2018 by Evan Gough

Gas and Dust Seen Swirling Around our Galaxy’s Supermassive Black Hole

ALMA images show gas and dust swirling around the supermassive black hole at the center of the Milky Way. Image Credit: ALMA (ESO/NAOJ/NRAO)/ J. R. Goicoechea (Instituto de Física Fundamental, CSIC, Spain)

At the heart of the Milky Way Galaxy lurks a Supermassive Black Hole (SMBH) named Sagittarius A* (Sag. A-star). Sag. A* is an object of intense study, even though you can’t actually see it. But new images from the Atacama Large Millimetre/sub-millimetre Array (ALMA) reveal swirling high-speed clouds of gas and dust orbiting the black hole, the next best thing to seeing the hole itself.

Continue reading “Gas and Dust Seen Swirling Around our Galaxy’s Supermassive Black Hole”

October 16, 2018 by Evan Gough

Here’s What the First Images from the Event Horizon Might Look Like

Researchers using the Event Horizon Telescope hope to generate more and better images like this of supermassive black hole Sag. A's event horizon. Image Credit: EHT.

The largest object in our night sky—by far!—is invisible to us. The object is the Super-Massive Black Hole (SMBH) at the center of our Milky Way galaxy, called Sagittarius A. But soon we may have an image of Sagittarius A’s event horizon. And that image may pose a challenge to Einstein’s Theory of General Relativity.

Continue reading “Here’s What the First Images from the Event Horizon Might Look Like”