Our universe is speckled with stars, with billions just in our galaxy. Some stars live alone or in twos or threes, but others are bound together by gravity into much larger communities. In honor of @NASAHubble’s exploration of #StarrySights, let’s talk about star clusters! 🧵 1/6
Star clusters are divided into a few different types, based on how many stars are in a cluster and how tightly they’re bound by gravity. Stars in clusters typically have a shared origin, and they can live very close together or can be spread out over hundreds of light-years. 2/6
Globular clusters are stellar "dinosaurs" scattered throughout the universe, containing some of the oldest stars in the universe. These clusters can contain anywhere from tens of thousands to millions of stars, packed tightly together in a dense clump. 3/6
Open clusters have fewer members, usually a few hundred stars or less. Most open clusters are much younger than globular clusters, and they’re also much less dense and less tightly bound than globular clusters. 4/6
Scientists are interested in how star clusters form and evolve. Some disperse and spread out over time, while others remain tightly bound together by gravity. The different types of stars in clusters also have various life spans, so they change and die off as a cluster ages. 5/6
Many different @NASA observatories study star clusters using different types of light. Alongside @NASAHubble, we’ll be highlighting how some of our other telescopes help us learn about these stellar communities! 6/6
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Love a morally gray love interest? Black holes are a great example since they have the perfect air of mystery to get away with the dramatic relationships they maintain. From long-term love to one-sided situationships, black holes do it all. go.nasa.gov/46f0skR
Some supermassive black holes, ones that are millions to billions of times the mass of our Sun, are basically childhood sweethearts with the galaxies that form around them — like Sagittarius A* and our own Milky Way.
But relationships aren’t always so sweet. When a star falls head-over-heels for a supermassive black hole, it can be torn apart by gravity in a tidal disruption event. Talk about a bad break-up. 💔
Did you know that black holes can be social? Let’s look at black holes that are scattered across our galaxy. Most of them have dance partners that can make them easier to detect. #BlackHoleWeek 🧵1/6
This dance starts before there’s a black hole in the picture. Most stars are born with at least one companion, and if either is large enough — 20+ times the Sun’s mass — it will explode as a supernova at the end of its life and leave a black hole. 2/6 science.nasa.gov/universe/the-l…
Since there’s nothing special about the gravity of a black hole, these two can continue their dance. However, there are ways they can interact that make them easier to spot. 3/6
#OTD 15 years ago, our Kepler telescope launched to detect planets outside our solar system. Before it retired in 2018, it helped us find thousands of new worlds … and much more!
Follow this thread for a few of our favorite discoveries! 🧵
Kepler’s steady gaze helped it spot the subtle dimming of a star’s light when a planet passed between us and the star. And it also helped Kepler see a supernova shockwave as it reached the surface of a star — an early moment in an unpredictable event: jpl.nasa.gov/news/nasas-kep…
Our Sun takes about a month to spin around once, but some larger stars take just a few days. Some spin so quickly, they’re squashed into a pumpkin shape! Kepler and Swift helped us find a batch of these rare stars and studied their extreme activity: nasa.gov/universe/nasa-…
You’ve heard that you’re made of star stuff, but what does that mean? The chemical elements in our bodies — and everything else around us — were made in space billions of years ago, before our solar system formed. So where did some of your elements come from? #PeriodicTableDay
The hydrogen that makes up the water in your body was formed during the big bang.
The nitrogen in your DNA was once inside small stars. Those stars shed their outer layers at the ends of their lives, forming planetary nebulae and freeing their nitrogen to become part of our solar system.
Are you enjoying our #BlackHoleFriday coverage? Like listening to podcasts? Then grab your headphones and dive into the black-hole-themed podcasts we’ve curated in this thread! 🎧 #BlackHoleFriday
The Small Steps, Giant Leaps podcast interviewed Fiona Harrison, the NuSTAR PI, for the X-ray telescope’s 10th anniversary. She talks about its biggest black hole findings and other cool things we’ve learned over the past decade: go.nasa.gov/3u1B4wo#BlackHoleFriday
Gravity Assist was the perfect podcast for Jeremy Schnittman to talk about black holes because they’re all about gravity! 🎧 Get some black hole basics and find out what Jeremy hopes we’ll discover someday: go.nasa.gov/3EBoV6f#BlackHoleFriday
This week in 2008, our Fermi Gamma-ray Space Telescope launched. Since then it has been our eyes on the gamma-ray sky! Follow this thread for some science highlights, and read more about Fermi and gamma rays in this Tumblr post: tmblr.co/Zz_Uqj2TjyFug#FermiFriday
Some of the universe’s brightest sources of light are black holes in the centers of galaxies! Black holes can turn galaxies into cosmic flashlights, and our Fermi telescope is helping us learn more about them: tmblr.co/Zz_Uqj2VhC7pa
Did you know our Milky Way galaxy is blowing bubbles? Two of them, each 25,000 light-years tall! They extend above and below the disk of the galaxy, like the two halves of an hourglass. We can’t see them, but our Fermi telescope can, in gamma-ray light: tmblr.co/Zz_Uqj2dMNkMX