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At the center of the Crab Nebula, located in the constellation Taurus, lies a celestial "beating heart" that is an example of extreme physics in space. The tiny object blasts out blistering pulses of radiation 30 times a second with unbelievable clock-like precision. Astronomers soon figured out that it was the crushed core of an exploded star, called a neutron star, which wildly spins like a blender on puree. The burned-out stellar core can do this without flying apart because it is 10 billion times stronger than steel. This incredible density means that the mass of 1.4 suns has been crushed into a solid ball of neutrons no bigger than the width of a large city. This Hubble image captures the region around the neutron star. It is unleashing copious amounts of energy that are pushing on the expanding cloud of debris from the supernova explosion — like an animal rattling its cage. This includes wave-like tsunamis of charged particles embedded in deadly magnetic fields.

On July 4, 1054, Chinese astronomers recorded the supernova that formed the Crab Nebula. The ultimate celestial firework, this "guest star" was visible during the daytime for 23 days, shining six times brighter than the planet Venus. The supernova was also recorded by Japanese, Arabic, and Native American stargazers. While searching for a comet that was predicted to return in 1758, French astronomer Charles Messier discovered a hazy nebula in the direction of the long-vanished supernova. He would later add it to his celestial catalog as "Messier 1." Because M1 didn't move across the sky like a comet, Messier simply ignored it other than just marking it as a "fake comet." Nearly a century later the British astronomer William Parsons sketched the nebula. Its resemblance to a crustacean led to M1's other name, the Crab Nebula. In 1928 Edwin Hubble first proposed associating the Crab Nebula to the Chinese "guest star" of 1054.

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      Last Updated Mar 31, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center
      Contact Media Claire Andreoli
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      Media Contacts
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      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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      Image B: Low Mass Objects within the Flame Nebula in Infrared Light
      This near-infrared image of a portion of the Flame Nebula from NASA’s James Webb Space Telescope highlights three low-mass objects, seen in the insets to the right. These objects, which are much colder than protostars, require the sensitivity of Webb’s instruments to detect them. These objects were studied as part of an effort to explore the lowest mass limit of brown dwarfs within the Flame Nebula.
      The Webb images represent light at wavelengths of 1.15 microns and 1.4 microns (filters F115W and F140M) as blue, 1.82 microns (F182M) as green, 3.6 microns (F360M) as orange, and 4.3 microns (F430M) as red. NASA, ESA, CSA, STScI, M. Meyer (University of Michigan) Building on Hubble’s Legacy
      Brown dwarfs, given the difficulty of finding them, have a wealth of information to provide, particularly in star formation and planetary research given their similarities to both stars and planets. NASA’s Hubble Space Telescope has been on the hunt for these brown dwarfs for decades.
      Even though Hubble can’t observe the brown dwarfs in the Flame Nebula to as low a mass as Webb can, it was crucial in identifying candidates for further study. This study is an example of how Webb took the baton—decades of Hubble data from the Orion Molecular Cloud Complex—and enabled in-depth research.
      “It’s really difficult to do this work, looking at brown dwarfs down to even ten Jupiter masses, from the ground, especially in regions like this. And having existing Hubble data over the last 30 years or so allowed us to know that this is a really useful star-forming region to target. We needed to have Webb to be able to study this particular science topic,” said De Furio.
      “It’s a quantum leap in our capabilities between understanding what was going on from Hubble. Webb is really opening an entirely new realm of possibilities, understanding these objects,” explained astronomer Massimo Robberto of the Space Telescope Science Institute.
      This team is continuing to study the Flame Nebula, using Webb’s spectroscopic tools to further characterize the different objects within its dusty cocoon. 
      “There’s a big overlap between the things that could be planets and the things that are very, very low mass brown dwarfs,” Meyer stated. “And that’s our job in the next five years: to figure out which is which and why.”
      These results are accepted for publication in The Astrophysical Journal Letters.
      Image C (Animated): Flame Nebula (Hubble and Webb Comparison)
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      Downloads
      Click any image to open a larger version.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Matthew Brown – mabrown@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Christine Pulliam – cpulliam@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
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      Last Updated Mar 10, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
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