“I loathe the poison dripping down from generation to generation. And I’d rather die than inflict the same thing on our children.”
-Patrick Melrose (2018) dir. Edward Berger
soft ♡
I just arrived home from seeing Declan McKenna!! 🇲🇽👍🏼 this kid is amazing, so much better than i thought!! And i had the opportunity to see him so close!!! 😍😍👏🏼👏🏼
Carrizo Plain National Monument, California by Quan Yuan Photo
We’re learning more every day about black holes thanks to one of the instruments aboard the International Space Station! Our Neutron star Interior Composition Explorer (NICER) instrument is keeping an eye on some of the most mysterious cosmic phenomena.
We’re going to talk about some of the amazing new things NICER is showing us about black holes. But first, let’s talk about black holes — how do they work, and where do they come from? There are two important types of black holes we’ll talk about here: stellar and supermassive. Stellar mass black holes are three to dozens of times as massive as our Sun while supermassive black holes can be billions of times as massive!
Stellar black holes begin with a bang — literally! They are one of the possible objects left over after a large star dies in a supernova explosion. Scientists think there are as many as a billion stellar mass black holes in our Milky Way galaxy alone!
Supermassive black holes have remained rather mysterious in comparison. Data suggest that supermassive black holes could be created when multiple black holes merge and make a bigger one. Or that these black holes formed during the early stages of galaxy formation, born when massive clouds of gas collapsed billions of years ago. There is very strong evidence that a supermassive black hole lies at the center of all large galaxies, as in our Milky Way.
Imagine an object 10 times more massive than the Sun squeezed into a sphere approximately the diameter of New York City — or cramming a billion trillion people into a car! These two examples give a sense of how incredibly compact and dense black holes can be.
Because so much stuff is squished into such a relatively small volume, a black hole’s gravity is strong enough that nothing — not even light — can escape from it. But if light can’t escape a dark fate when it encounters a black hole, how can we “see” black holes?
Scientists can’t observe black holes directly, because light can’t escape to bring us information about what’s going on inside them. Instead, they detect the presence of black holes indirectly — by looking for their effects on the cosmic objects around them. We see stars orbiting something massive but invisible to our telescopes, or even disappearing entirely!
When a star approaches a black hole’s event horizon — the point of no return — it’s torn apart. A technical term for this is “spaghettification” — we’re not kidding! Cosmic objects that go through the process of spaghettification become vertically stretched and horizontally compressed into thin, long shapes like noodles.
Scientists can also look for accretion disks when searching for black holes. These disks are relatively flat sheets of gas and dust that surround a cosmic object such as a star or black hole. The material in the disk swirls around and around, until it falls into the black hole. And because of the friction created by the constant movement, the material becomes super hot and emits light, including X-rays.
At last — light! Different wavelengths of light coming from accretion disks are something we can see with our instruments. This reveals important information about black holes, even though we can’t see them directly.
So what has NICER helped us learn about black holes? One of the objects this instrument has studied during its time aboard the International Space Station is the ever-so-forgettably-named black hole GRS 1915+105, which lies nearly 36,000 light-years — or 200 million billion miles — away, in the direction of the constellation Aquila.
Scientists have found disk winds — fast streams of gas created by heat or pressure — near this black hole. Disk winds are pretty peculiar, and we still have a lot of questions about them. Where do they come from? And do they change the shape of the accretion disk?
It’s been difficult to answer these questions, but NICER is more sensitive than previous missions designed to return similar science data. Plus NICER often looks at GRS 1915+105 so it can see changes over time.
NICER’s observations of GRS 1915+105 have provided astronomers a prime example of disk wind patterns, allowing scientists to construct models that can help us better understand how accretion disks and their outflows around black holes work.
NICER has also collected data on a stellar mass black hole with another long name — MAXI J1535-571 (we can call it J1535 for short) — adding to information provided by NuSTAR, Chandra, and MAXI. Even though these are all X-ray detectors, their observations tell us something slightly different about J1535, complementing each other’s data!
This rapidly spinning black hole is part of a binary system, slurping material off its partner, a star. A thin halo of hot gas above the disk illuminates the accretion disk and causes it to glow in X-ray light, which reveals still more information about the shape, temperature, and even the chemical content of the disk. And it turns out that J1535’s disk may be warped!
Image courtesy of NRAO/AUI and Artist: John Kagaya (Hoshi No Techou)
This isn’t the first time we have seen evidence for a warped disk, but J1535’s disk can help us learn more about stellar black holes in binary systems, such as how they feed off their companions and how the accretion disks around black holes are structured.
NICER primarily studies neutron stars — it’s in the name! These are lighter-weight relatives of black holes that can be formed when stars explode. But NICER is also changing what we know about many types of X-ray sources. Thanks to NICER’s efforts, we are one step closer to a complete picture of black holes. And hey, that’s pretty nice!
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‘Talia’ by King Princess (2018) dir. Clare Gillen
NASA’s newest planet-hunting satellite — the Transiting Exoplanet Survey Satellite, or TESS for short — has just released its first science image using all of its cameras to capture a huge swath of the sky! TESS is NASA’s next step in the search for planets outside our solar system, called exoplanets.
This spectacular image, the first released using all four of TESS’ cameras, shows the satellite’s full field of view. It captures parts of a dozen constellations, from Capricornus (the Sea Goat) to Pictor (the Painter’s Easel) — though it might be hard to find familiar constellations among all these stars! The image even includes the Large and Small Magellanic Clouds, our galaxy’s two largest companion galaxies.
The science community calls this image “first light,” but don’t let that fool you — TESS has been seeing light since it launched in April. A first light image like this is released to show off the first science-quality image taken after a mission starts collecting science data, highlighting a spacecraft’s capabilities.
TESS has been busy since it launched from NASA’s Kennedy Space Center in Cape Canaveral, Florida. First TESS needed to get into position, which required a push from the Moon. After nearly a month in space, the satellite passed about 5,000 miles from the Moon, whose gravity gave it the boost it needed to get into a special orbit that will keep it stable and maximize its view of the sky.
During those first few weeks, we also got a sneak peek of the sky through one of TESS’s four cameras. This test image captured over 200,000 stars in just two seconds! The spacecraft was pointed toward the constellation Centaurus when it snapped this picture. The bright star Beta Centauri is visible at the lower left edge, and the edge of the Coalsack Nebula is in the right upper corner.
After settling into orbit, scientists ran a number of checks on TESS, including testing its ability to collect a set of stable images over a prolonged period of time. TESS not only proved its ability to perform this task, it also got a surprise! A comet named C/2018 N1 passed through TESS’s cameras for about 17 hours in July.
The images show a treasure trove of cosmic curiosities. There are some stars whose brightness changes over time and asteroids visible as small moving white dots. You can even see an arc of stray light from Mars, which is located outside the image, moving across the screen.
Now that TESS has settled into orbit and has been thoroughly tested, it’s digging into its main mission of finding planets around other stars. How will it spot something as tiny and faint as a planet trillions of miles away? The trick is to look at the star!
So far, most of the exoplanets we’ve found were detected by looking for tiny dips in the brightness of their host stars. These dips are caused by the planet passing between us and its star – an event called a transit. Over its first two years, TESS will stare at 200,000 of the nearest and brightest stars in the sky to look for transits to identify stars with planets.
TESS will be building on the legacy of NASA’s Kepler spacecraft, which also used transits to find exoplanets. TESS’s target stars are about 10 times closer than Kepler’s, so they’ll tend to be brighter. Because they’re closer and brighter, TESS’s target stars will be ideal candidates for follow-up studies with current and future observatories.
TESS is challenging over 200,000 of our stellar neighbors to a staring contest! Who knows what new amazing planets we’ll find?
The TESS mission is led by MIT and came together with the help of many different partners. You can keep up with the latest from the TESS mission by following mission updates.
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Bjork
“Al igual que la luz, le atrae la oscuridad. Sabe que en nuestro tiempo se considera ridículo apagar la luz mientras se hace el amor y por eso deja encendida una pequeña lámpara encima de la cama. Pero cuando la penetra, cierra los ojos. El gozo que le inunda requiere oscuridad. Esa oscuridad es pura, limpia, sin imágenes ni visiones, esa oscuridad no tiene final, no tiene fronteras, esa oscuridad es el infinito que cada uno de nosotros lleva dentro de sí.”
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