As they die, massive stars—at least 8 times bigger than our sun—populate the universe with new elements. How does that happen? We’ll show you each step! 👇🏼 (1/7)
Credit: NASA, ESA, and L. Hustak (STScI).
Stars don’t normally explode 💥 because they balance two forces: gravity, which wants to crush all of the gas towards the center, and pressure from fusion, which pushes outward.
The first stage of a star’s life is fueled by hydrogen-to-helium fusion. (2/7)
Over a star’s lifetime, the core will run out of fuel, contract and heat up, and begin new fusion reactions.
This creates a multi-layered core, with heavier elements fusing in the hot, dense center and shells of lighter elements fusing at cooler temperatures. (3/7)
The shell-building process begins when a star runs out of hydrogen in its core.
Gravity crushes the core, making it hotter and smaller. Eventually, it gets hot enough to fuse helium into carbon, surrounded by a shell that fuses hydrogen into helium. (4/7)
The after the core exhausts its helium supply, the process repeats. The carbon core contracts further and reaches high enough temperatures to fuse carbon into oxygen, then silicon, and finally to iron. Some of these steps take thousands of years. Others take a single day.🤯 (5/7)
When the iron core cannot produce energy to balance the weight of the surrounding gas, it collapses. Boom, SUPERNOVA! In less than a second, the star implodes & then explodes, leaving behind a supernova remnant. Elements created inside the 🌟/💥 spread through the universe. (6/7)
All of these steps that highlight the engines of creation can be found in one amazing—and downloadable—graphic 👉🏼 bit.ly/3I4Fubj (7/7)
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We have the right tools for the job! @NASAWebb has four instruments that will examine the universe in different ways, thanks to the six components that make up the devices. (1/8) #WebbInstruments#UnfoldTheUniverse
Cameras: Three Webb instruments have cameras 📷 that will capture two-dimensional images of regions in space. NIRCam and NIRISS will capture images in the near-infrared, while MIRI will capture mid-infrared images. (2/8)
Spectrographs: All four of Webb’s instruments have spectrographs that spread light out into a rainbow-like spectrum 🌈 so the brightness of each individual wavelength can be measured. Webb has different types of spectrographs, each designed for a slightly different purpose. (3/8)
Science discoveries made by @NASAWebb are expected to revolutionize our understanding of the cosmos and our origins within the universe! Dive into what Webb could reveal about the cosmos: bit.ly/3wJ1r9U Credit: ESO/M. Kornmesser. #AAS238 (1/9)
Mission goals for Webb include: Search for the first galaxies that formed in early universe; study the evolution of galaxies; observe star formation; and measure physical and chemical properties and investigate the potential for life in planetary systems. #AAS238 (2/9)
Webb is equipped with specialized instruments that detect infrared wavelengths, the light just beyond the visible spectrum. Infrared radiation can penetrate dense molecular clouds, whose dust blocks most of the light detectable by Hubble. Credit: NASA/JPL-Caltech #AAS238 (3/9)
Research telescopes include scientific instruments that record light precisely. The extreme sensitivity and precision of @NASAWebb’s four instruments support its unprecedented scientific power: bit.ly/3fIQm35 Credit: NASA. #AAS238 (1/7)
Each of Webb’s four instruments is like a Swiss army knife of specialized components, with multiple ways of observing. All four can be used for investigations of the wide variety of objects that make up the universe, including planets, stars, nebulae, and galaxies. #AAS238 (2/7)
Webb’s instruments are housed in the Integrated Science Instrument Module (ISIM), which is situated behind the primary mirror on the cold side of the telescope where it is protected by the sunshield. Credit: NASA and STScI. #AAS238 (3/7)
The bigger the telescope, the better its vision. @NASAWebb is the largest telescope NASA has ever sent into space. Webb is designed to be as light as possible, but still measure large enough to achieve its scientific goals: bit.ly/3icJRa4 Credit: NASA. #AAS238 (1/10)
Webb’s key components include an enormous primary mirror to collect infrared light, a supersized sunshield to keep the telescope cold, and four scientific instruments to conduct its ambitious science operations. Credit: NASA. #AAS238 (2/10)
Webb’s primary mirror towers more than two stories high. For the telescope to fit in the launch vehicle, an Ariane 5 rocket, it must fold origami-style to about a quarter of its full size, then unfold on its way to its orbit location. #AAS238 (3/10)