Astronomers Find A ‘Cloaked’ Black Hole 500 Million Years Before Any Other
“The first stars should lead to modest black holes: hundreds or thousands of solar masses. But when we see the Universe’s first black holes, they’re already ~1 billion solar masses. The leading idea is black holes form and merge, and then rapidly accrete matter at maximal rates. But those rapidly growing black holes should be invisible, obscured by the dense gas clouds they feed upon. They were, until now. New observations have revealed the earliest “cloaked” black hole ever.”
How do black holes get so big so quickly in this Universe? It’s one of the great mysteries in astrophysics, but the hope has been that better observations of the first billion years of the Universe will help solve this puzzle. If the seeds of black holes can gather enough gas around them to feed on, they just might get there. But the difficultly then comes in locating and finding these obscured, “cloaked” black holes. While they’ve been found relatively nearby, telling us that such a phenomenon does occur, they’ve never been found at very early times: within the first billion years of the Universe.
Well, with new Chandra X-ray observations, all of that has changed. We found a cloaked black hole just 850 million years after the Big Bang. It might be the key to solving this cosmic puzzle at long last.
Meet The Largest X-Ray Jet In The Universe
“Like all known active galaxies, Pictor A is powered by a supermassive black hole many millions to billions of times our Sun’s mass. Black holes can accelerate and eject infalling matter, leading to intense emissions. The light released spans the spectrum from high-energy X-rays to low-energy radio waves. The radio lobes of gas provide a medium for high-energy X-rays to interact with. When these interactions cause electrons to exceed the speed of sound in the gaseous medium, it creates intense shock waves.”
When you have an active galaxy, you can be pretty certain that there’s a supermassive black hole feeding on some matter nearby. If you’ve been paying attention, you’ll know that black holes don’t just devour matter, but that most of the matter that encounters them gets accelerated and ejected instead. This create large lobes of radio-emitting gas around many such galaxies, and in this one in particular, Pictor A, that provides exactly the right environment to create a spectacular feature. X-ray emissions, with energies many times that required to ionize atoms and molecules, slam into that matter, causing it to create free electrons that exceed the speed of sound in that medium. The result is that we get shock waves, and an overall X-ray jet that’s some 300,000 light-years long.
That makes this galaxy the one with the largest known X-ray jet in the Universe so far! Come get the full story, and many more beautiful images, here!
The Most Important X-Ray Image Ever Taken Proved The Existence Of Dark Matter
“Yet the most important X-ray image of all time was an incredible surprise. This is the Bullet Cluster: a system of two galaxy clusters colliding at high speeds. As the gaseous matter inside collides, it slows, heats up, and lags behind, emitting X-rays. However, we can use gravitational lensing to learn where the mass is located in this system. he bending and shearing of light from background galaxies shows it’s separated from the matter’s and X-rays’ location. This separation is some of our strongest evidence for dark matter.”
There are many different lines of evidence for dark matter, but one of the biggest contentions of those who disbelieve it is that a direct empirical proof of its existence is needed. If it exists in a large, diffuse halo around every galaxy, cluster, and component of large-scale structure in the Universe, you should be able to prove it. Starting more than 10 years ago, astronomers have been able to do just that. When galaxy clusters collide, the overwhelming majority of normal matter, residing in the intracluster medium, should smash together, heat up, and emit X-rays. It does! But the biggest deal is that the gravitational mass, reconstructed through lensing, doesn’t coincide with the normal matter.
There must be some other type of matter from the normal, baryonic matter. Ergo, dark matter. Here’s (IMO) the most important X-ray story of all-time.
The Pillars Of Creation Haven’t Been Destroyed, Say New NASA Images
“Near-infrared observations can see through the dust, revealing a glittering tapestry of young, hot stars inside. But at longer wavelengths, cooler-temperature objects show up. Mid-infrared light revealed that a diffuse heat source was warming the nebula, suggesting a recent supernova. While the far-infrared showed where the gas is evaporating, we needed X-rays to know if the pillars were being destroyed.”
In a stunning new release, NASA’s Chandra X-ray observatory has put out a wide-field view of a large portion of the Eagle Nebula, including the famed Pillars of Creation. All told, some 1,700 X-ray sources were identified, perhaps 2/3rds of which are inside the nebula. There are proto-stars, young stars, and stellar corpses. But conspicuously missing from the entire field-of-view is any evidence of a supernova remnant. In 2007, infrared data from Spitzer suggested that there may have been a recent supernova, and hence the pillars may already have been destroyed. The new Chandra data weighs in on that, giving a definitive “no” for an answer.
Come see the incredible suite of images and learn about the science inside this cosmic beauty, on today’s Mostly Mute Monday!
Astrophysics Reveals The Origin Of The Human Body
“Owing to NASA’s Chandra X-ray telescope, we can observe how much of each heavy element comes from recent supernova explosions.
When it comes to the human body, the majority of what makes us up comes from supernovae, not any other source.
The biggest find? Every element required to make DNA is found in the aftermath of exploding stars.”
From hydrogen through uranium and beyond, the Universe finds a way to create more than 90 unique elements via natural processes. Dozens of those elements have been found in the human body, many of which are essential to life processes. Yet every element has its own unique cosmic origin story, from the Big Bang to small stars to supernovae to neutron star mergers and more. Using data from NASA’s Chandra X-ray telescope, we’ve measured which elements are produced in supernova explosions, and in what concentrations. Not only have we determined that the overwhelming majority of the human body’s components (73%) are produced in supernovae, but that almost all of our oxygen, by far our most abundant element, is made there. Other processes play a role, but the majority of each of us comes from an exploding, massive star.
Come find out the true, full origin of the elements that made you, a truly cosmic story!
Ask Ethan: How Many Black Holes Are There In The Universe?
“The most recent LIGO event made me wonder how numerous black holes are, and that made me wonder what the sky would look like if we could see them (and, for clarity, see *only* black holes)… what is the spatial and intensity distribution of black holes compared the distribution of visible stars?”
For the third time since it began taking data, the LIGO collaboration discovered direct evidence for merging black holes in the Universe. There’s an incredible amount we’ve learned about black holes and where they’re located, however, and very little of it comes from gravitational waves. Instead, we know how black holes are made, where their progenitors are and were located, and how they’re likely to be distributed today. If we put this picture all together, we can come up with a numerical estimate for how many are likely to be present in our galaxy, along with where they’re expected to be concentrated. It’s an incredible picture!
Just a few decades ago, we weren’t sure black holes even existed; now we think we know where millions ought to be in every galaxy. Come get the remarkable story on this week’s Ask Ethan!