Astronaut Journal Entry - Unusual Attitude Recovery

What’s your favorite black hole fact that you like to share with people?

Thank you for joining the #CountdownToMars! The Mars Perseverance Answer Time with expert Chloe Sackier is LIVE!

Stay tuned for talks about landing a rover on Mars, Perseverance's science goals on the Red Planet, landing a career at NASA and more. View ALL the answers HERE. 

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Top 10 Ways the Space Station is Helping Get Us to Mars

Believe it or not, the International Space Station is paving our way to Mars. Being the only microgravity laboratory in which long-duration investigations can take place, it provides deeper understanding of how the human body reacts to long-term spaceflight. Here are the top 10 ways the space station is helping us on our journey to the Red Planet:

10: Communication Delays

Have you ever sent a text and got frustrated when it took longer than 3 seconds to send? Imaging communicating from Mars where round-trip delays could take up to 31 minutes! Our Comm Delay Assessment studies the effects of delayed communications for interplanetary crews that have to handle medical and other emergencies in deep space.

9. Astronaut Functional Performance

After a long nights sleep, do you ever feel a bit clumsy when you first get out of bed? Imagine how crew members might feel after spending six months to a year in microgravity! Our Field Test investigation is working to understand the extend of physical changes in astronauts who live in space for long periods of time, with an aim toward improving recovery time and developing injury prevention methods for future missions.

8. Psychological Impacts of Isolation and Confinement

In order to study the behavioral issues associated with isolation and confinement, researchers evaluate the personal journals of space station crew members. These study results provide information to help prepare us for longer duration spaceflight.

7. Impacts on Vision

Did you know that long duration spaceflight can often cause changes to crew members’ vision? It can, and our Ocular Health study monitors microgravity-induced visual impairment, as well as changes believed to arise from elevated intracranial pressure. All of this work hopes to characterize how living in microgravity can affect the visual, vascular and central nervous systems.

6. Immune Responses

An important aspect of our journey to Mars is the need to understand how long-duration spaceflight affects they way crew members’ bodies defend agains pathogens. Our Integrated Immune investigation collects and analyzes blood, urine and saliva samples from crew members before, during and after spaceflight to monitor changes in the immune system.

5. Food for Long-Duration Crews

Just like a hiker preparing for a long trek, packing the foods that will give you the most energy for the longest amount of time is key to your success. This is also true for astronauts on long-duration missions. Our Energy investigation measures a crew members’ energy requirements, which is a crucial factor needed for sending the correct amount of the right types of food to space.

4. Exercise for Long-Term Missions

Rigorous exercise is already a regular part of astronauts’ routines, and continuing that focus will be critical to keeping crew members’ bodies strong and ready for a mission to Mars and a healthy return to Earth. Our Sprint investigation is studying the best combination of intensity and duration for exercise in space.

3. Determine Best Habitat/Environment for Crews

Have you ever complained about your room being too small? Imagine living in cramped quarters with an entire crew for months on a Mars mission! Our Habitability investigation collects observations that will help spacecraft designers understand how much habitable volume is required, and whether a mission’s duration impacts how much space crew members need.

2. Growing Food in Space

There’s nothing like fresh food. Not only does it provide valuable nutrition for astronauts, but can also offer psychological benefits from tending and harvesting the crops. Our Veggie investigation studies how to best utilize a facility aboard the space station for growing fresh produce in microgravity.

1. Manufacturing Items in Space

When crews head to Mars, there may be items that are unanticipated or that break during the mission. Our 3-D Printing in Zero-G Technology Demonstration would give crews the ability to manufacture new objects on demand while in space.

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The Big Build: Artemis I Stacks Up

Our Space Launch System (SLS) rocket is coming together at the agency’s Kennedy Space Center in Florida this summer. Our mighty SLS rocket is set to power the Artemis I mission to send our Orion spacecraft around the Moon. But, before it heads to the Moon, NASA puts it together right here on Earth.

Read on for more on how our Moon rocket for Artemis I will come together this summer:

Get the Base

How do crews assemble a rocket and spacecraft as tall as a skyscraper? The process all starts inside the iconic Vehicle Assembly Building at Kennedy with the mobile launcher. Recognized as a Florida Space Coast landmark, the Vehicle Assembly Building, or VAB, houses special cranes, lifts, and equipment to move and connect the spaceflight hardware together. Orion and all five of the major parts of the Artemis I rocket are already at Kennedy in preparation for launch. Inside the VAB, teams carefully stack and connect the elements to the mobile launcher, which serves as a platform for assembly and, later, for fueling and launching the rocket.

Start with the boosters

Because they carry the entire weight of the rocket and spacecraft, the twin solid rocket boosters for our SLS rocket are the first elements to be stacked on the mobile launcher inside the VAB. Crews with NASA’s Exploration Ground Systems and contractor Jacobs team completed stacking the boosters in March. Each taller than the Statue of Liberty and adorned with the iconic NASA “worm” logo, the five-segment boosters flank either side of the rocket’s core stage and upper stage. At launch, each booster produces more than 3.6 million pounds of thrust in just two minutes to quickly lift the rocket and spacecraft off the pad and to space.

Bring in the core stage

In between the twin solid rocket boosters is the core stage. The stage has two huge liquid propellant tanks, computers that control the rocket’s flight, and four RS-25 engines. Weighing more than 188,000 pounds without fuel and standing 212 feet, the core stage is the largest element of the SLS rocket. To place the core stage in between the two boosters, teams will use a heavy-lift crane to raise and lower the stage into place on the mobile launcher.

On launch day, the core stage’s RS-25 engines produce more than 2 million pounds of thrust and ignite just before the boosters. Together, the boosters and engines produce 8.8 million pounds of thrust to send the SLS and Orion into orbit.

Add the Launch Vehicle Stage Adapter

Once the boosters and core stage are secured, teams add the launch vehicle stage adapter, or LVSA, to the stack. The LVSA is a cone-shaped element that connects the rocket’s core stage and Interim Cryogenic Propulsion Stage (ICPS), or upper stage. The roughly 30-foot LVSA houses and protects the RL10 engine that powers the ICPS. Once teams bolt the LVSA into place on top of the rocket, the diameter of SLS will officially change from a wide base to a more narrow point — much like a change in the shape of a pencil from eraser to point.

Lower the Interim Cryogenic Propulsion Stage into place

Next in the stacking line-up is the Interim Cryogenic Propulsion Stage or ICPS. Like the LVSA, crews will lift and bolt the ICPS into place. To help power our deep space missions and goals, our SLS rocket delivers propulsion in phases. At liftoff, the core stage and solid rocket boosters will propel Artemis I off the launch pad. Once in orbit, the ICPS and its single RL10 engine will provide nearly 25,000 pounds of thrust to send our Orion spacecraft on a precise trajectory to the Moon.

Nearly there with the Orion stage adapter

When the Orion stage adapter crowns the top of the ICPS, you’ll know we’re nearly complete with stacking SLS rocket for Artemis I. The Orion Stage Adapter is more than just a connection point. At five feet in height, the Orion stage adapter may be small, but it holds and carries several small satellites called CubeSats. After Orion separates from the SLS rocket and heads to the Moon, these shoebox-sized payloads are released into space for their own missions to conduct science and technology research vital to deep space exploration. Compared to the rest of the rocket and spacecraft, the Orion stage adapter is the smallest SLS component that’s stacked for Artemis I.

Top it off

Finally, our Orion spacecraft will be placed on top of our Moon rocket inside the VAB. The final piece will be easy to spot as teams recently added the bright red NASA “worm” logotype to the outside of the spacecraft. The Orion spacecraft is much more than just a capsule built to carry crew. It has a launch abort system, which will carry the crew to safety in case of an emergency, and a service module developed by the European Space Agency that will power and propel the spacecraft during its three-week mission. On the uncrewed Artemis I mission, Orion will check out the spacecraft’s critical systems, including navigation, communications systems, and the heat shield needed to support astronauts who will fly on Artemis II and beyond.

Ready for launch!

The path to the pad requires many steps and check lists. Before Artemis I rolls to the launch pad, teams will finalize outfitting and other important assembly work inside the VAB. Once assembled, the integrated SLS rocket and Orion will undergo several final tests and checkouts in the VAB and on the launch pad before it’s readied for launch.

The Artemis I mission is the first in a series of increasingly complex missions that will pave the way for landing the first woman and the first person of color on the Moon. The Space Launch System is the only rocket that can send NASA astronauts aboard NASA’s Orion spacecraft and supplies to the Moon in a single mission.

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Mission Possible: Redirecting an Asteroid

As part of our Asteroid Redirect Mission (ARM), we plan to send a robotic spacecraft to an asteroid tens of millions of miles away from Earth, capture a multi-ton boulder and bring it to an orbit near the moon for future crew exploration.

This mission to visit a large near-Earth asteroid is part of our plan to advance the new technologies and spaceflight experience needed for a human mission to the Martian system in the 2030s.

How exactly will it work?

The robotic spacecraft, powered by the most advanced solar electric propulsion system, will travel for about 18 months to the target asteroid.

After the spacecraft arrives and the multi-ton boulder is collected from the surface, the spacecraft will hover near the asteroid to create a gravitational attraction that will slightly change the asteroid’s trajectory.

After the enhanced gravity tractor demonstration is compete, the robotic vehicle will deliver the boulder into a stable orbit near the moon. During the transit, the boulder will be further imaged and studied by the spacecraft.

Astronauts aboard the Orion spacecraft will launch on the Space Launch System rocket to explore the returned boulder.

Orion will dock with the robotic vehicle that still has the boulder in its grasp. 

While docked, two crew members on spacewalks will explore the boulder and collect samples to bring back to Earth for further study.

The astronauts and collected samples will return to Earth in the Orion spacecraft.

How will ARM help us send humans to Mars in the 2030s?

This mission will demonstrate future Mars-level exploration missions closer to home and will fly a mission with technologies and real life operational constraints that we’ll encounter on the way to the Red Planet. A few of the capabilities it will help us test include: 

Solar Electric Propulsion – Using advanced Solar Electric Propulsion (SEP) technologies is an important part of future missions to send larger payloads into deep space and to the Mars system. Unlike chemical propulsion, which uses combustion and a nozzle to generate thrust, SEP uses electricity from solar arrays to create electromagnetic fields to accelerate and expel charged atoms (ions) to create a very low thrust with a very efficient use of propellant.

Trajectory and Navigation – When we move the massive asteroid boulder using low-thrust propulsion and leveraging the gravity fields of Earth and the moon, we’ll validate critical technologies for the future Mars missions. 

Advances in Spacesuits – Spacesuits designed to operate in deep space and for the Mars surface will require upgrades to the portable life support system (PLSS). We are working on advanced PLSS that will protect astronauts on Mars or in deep space by improving carbon dioxide removal, humidity control and oxygen regulation. We are also improving mobility by evaluating advances in gloves to improve thermal capacity and dexterity. 

Sample Collection and Containment Techniques – This experience will help us prepare to return samples from Mars through the development of new techniques for safe sample collection and containment. These techniques will ensure that humans do not contaminate the samples with microbes from Earth, while protecting our planet from any potential hazards in the samples that are returned. 

Rendezvous and Docking Capabilities – Future human missions to Mars will require new capabilities to rendezvous and dock spacecraft in deep space. We will advance the current system we’ve developed with the international partners aboard the International Space Station. 

Moving from spaceflight a couple hundred miles off Earth to the proving ground environment (40,000 miles beyond the moon) will allow us to start accumulating experience farther than humans have ever traveled in space.

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Our Weird and Wonderful Galaxy of Black Holes

Black holes are hard to find. Like, really hard to find. They are objects with such strong gravity that light can’t escape them, so we have to rely on clues from their surroundings to find them.

When a star weighing more than 20 times the Sun runs out of fuel, it collapses into a black hole. Scientists estimate that there are tens of millions of these black holes dotted around the Milky Way, but so far we’ve only identified a few dozen. Most of those are found with a star, each circling around the other. Another name for this kind of pair is a binary system.That’s because under the right circumstances material from the star can interact with the black hole, revealing its presence. 

The visualization above shows several of these binary systems found in our Milky Way and its neighboring galaxy. with their relative sizes and orbits to scale. The video even shows each system tilted the way we see it here from our vantage point on Earth. Of course, as our scientists gather more data about these black holes, our understanding of them may change.   

If the star and black hole orbit close enough, the black hole can pull material off of its stellar companion! As the material swirls toward the black hole, it forms a flat ring called an accretion disk. The disk gets very hot and can flare, causing bright bursts of light.

V404 Cygni, depicted above, is a binary system where a star slightly smaller than the Sun orbits a black hole 10 times its mass in just 6.5 days. The black hole distorts the shape of the star and pulls material from its surface. In 2015, V404 Cygni came out of a 25-year slumber, erupting in X-rays that were initially detected by our Swift satellite. In fact, V404 Cygni erupts every couple of decades, perhaps driven by a build-up of material in the outer parts of the accretion disk that eventually rush in. 

In other cases, the black hole’s companion is a giant star with a strong stellar wind. This is like our Sun’s solar wind, but even more powerful. As material rushes out from the companion star, some of it is captured by the black hole’s gravity, forming an accretion disk.

A famous example of a black hole powered by the wind of its companion is Cygnus X-1. In fact, it was the first object to be widely accepted as a black hole! Recent observations estimate that the black hole’s mass could be as much as 20 times that of our Sun. And its stellar companion is no slouch, either. It weighs in at about 40 times the Sun.

We know our galaxy is peppered with black holes of many sizes with an array of stellar partners, but we've only found a small fraction of them so far. Scientists will keep studying the skies to add to our black hole menagerie.

Curious to learn more about black holes? Follow NASA Universe on Twitter and Facebook to keep up with the latest from our scientists and telescopes.

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A Total Solar Eclipse Revealed Solar Storms 100 Years Before Satellites

Just days from now, on Aug. 21, 2017, the Moon will pass between the Sun and Earth, casting its shadow down on Earth and giving all of North America the chance to see a solar eclipse. Remember that it is never safe to look at the partially eclipsed or uneclipsed Sun, so make sure you use a solar filter or indirect viewing method if you plan to watch the eclipse.

Eclipses set the stage for historic science. Past eclipses enabled scientists to study the Sun’s structure, find the first proof of Einstein’s theory of general relativity, and discover the element helium — 30 years before it was found on Earth..

We’re taking advantage of the Aug. 21 eclipse by funding 11 ground-based scientific studies. As our scientists prepare their experiments for next week, we’re looking back to an historic 1860 total solar eclipse, which many think gave humanity our first glimpse of solar storms — called coronal mass ejections — 100 years before scientists first understood what they were.  

Coronal mass ejections, or CMEs, are massive eruptions made up of hot gas, plasma and magnetic fields. Bursting from the Sun’s surface, these giant clouds of solar material speed into space up to a million miles per hour and carry enough energy to power the world for 10,000 years if we could harness it. Sometimes, when they’re directed towards Earth, CMEs can affect Earth’s space environment, creating space weather: including triggering auroras, affecting satellites, and – in extreme cases – even straining power grids.

Scientists observed these eruptions in the 1970s during the beginning of the modern satellite era, when satellites in space were able to capture thousands of images of solar activity that had never been seen before.

But in hindsight, scientists realized their satellite images might not be the first record of these solar storms. Hand-drawn records of an 1860 total solar eclipse bore surprising resemblance to these groundbreaking satellite images.

On July 18, 1860, the Moon’s shadow swept across North America, Spain and North Africa. Because it passed over so much populated land, this eclipse was particularly well-observed, resulting in a wealth of scientific observations.  

Drawings from across the path of the 1860 eclipse show large, white finger-like projections in the Sun’s atmosphere—called the corona—as well as a distinctive, bubble-shaped structure. But the observations weren’t uniform – only about two-thirds of the 1860 eclipse sketches showed this bubble, setting off heated debate about what this feature could have been.

Sketches from the total solar eclipse of July 1860.

One hundred years later, with the onset of space-based satellite imagery, scientists got another piece of the puzzle. Those illustrations from the 1860 eclipse looked very similar to satellite imagery showing CMEs – meaning 1860 may have been humanity’s first glimpse at these solar storms, even though we didn’t understand what we were seeing.

While satellites provide most of the data for CME research, total solar eclipses seen from the ground still play an important role in understanding our star. During an eclipse, observers on the ground are treated to unique views of the innermost corona, the region of the solar atmosphere that triggers CMEs.

This region of the Sun’s atmosphere can’t be measured at any other time, since human-made instruments that create artificial eclipses must block out much of the Sun’s atmosphere—as well as its bright face—in order to produce clear images. Yet scientists think this important region is responsible for accelerating CMEs, as well as heating the entire corona to extraordinarily high temperatures.

When the path of an eclipse falls on land, scientists take advantage of these rare chances to collect unique data. With each new total solar eclipse, there’s the possibility of new information and research—and maybe, the chance to reveal something as astronomical as the first solar storm.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21.

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Largest Collection of Planets EVER Discovered!

Guess what!? Our Kepler mission has verified 1,284 new planets, which is the single largest finding of planets to date. This gives us hope that somewhere out there, around a star much like ours, we can possibly one day discover another Earth-like planet.

But what exactly does that mean? These planets were previously seen by our spacecraft, but have now been verified. Kepler’s candidates require verification to determine if they are actual planets, and not another object, such as a small star, mimicking a planet. This announcement more than doubles the number of verified planets from Kepler.

Since the discovery of the first planets outside our solar system more than two decades ago, researchers have resorted to a laborious, one-by-one process of verifying suspected planets. These follow-up observations are often time and resource intensive. This latest announcement, however, is based on a statistical analysis method that can be applied to many planet candidates simultaneously.

They employed a technique to assign each Kepler candidate a planet-hood probability percentage – the first such automated computation on this scale, as previous statistical techniques focused only on sub-groups within the greater list of planet candidates identified by Kepler. 

What that means in English: Planet candidates can be thought of like bread crumbs. If you drop a few large crumbs on the floor, you can pick them up one by one. But, if you spill a whole bag of tiny crumbs, you're going to need a broom. This statistical analysis is our broom.

The Basics: Our Kepler space telescope measures the brightness of stars. The data will look like an EKG showing the heart beat. Whenever a planet passes in front of its parent star a viewed from the spacecraft, a tiny pulse or beat is produced. From the repeated beats, we can detect and verify the existence of Earth-size planets and learn about their orbits and sizes. This planet-hunting technique is also known as the Transit Method.

The number of planets by size for all known exoplanets, planets that orbit a sun-like star, can be seen in the above graph. The blue bars represent all previously verified exoplanets by size, while the orange bars represent Kepler’s 1,284 newly validated planets announced on May 10.

While our original Kepler mission has concluded, we have more than 4 years of science collected that produced a remarkable data set that will be used by scientists for decades. The spacecraft itself has been re-purposed for a new mission, called K2 -- an extended version of the original Kepler mission to new parts of the sky and new fields of study.

The above visual shows all the missions we’re currently using, and plan to use, in order to continue searching for signs of life beyond Earth.

Following Kepler, we will be launching future missions to continue planet-hunting , such as the Transiting Exoplanet Survey Satellite (TESS), and the James Webb Space Telescope. We hope to continue searching for other worlds out there and maybe even signs of life-as-we-know-it beyond Earth.

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Boo! Did we get you? 🎃

This solar jack-o-lantern, captured by our Solar Dynamics Observatory (SDO) in October 2014, gets its ghoulish grin from active regions on the Sun, which emit more light and energy than the surrounding dark areas. Active regions are markers of an intense and complex set of magnetic fields hovering in the sun’s atmosphere.

The SDO has kept an unblinking eye on the Sun since 2010, recording phenomena like solar flares and coronal loops. It measures the Sun’s interior, atmosphere, magnetic field, and energy output, helping us understand our nearest star.

Grab the high-resolution version here.

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Black Holes are NICER Than You Think!

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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