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NASA's Hubble Space Telescope has been

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observing the Crab Nebula for decades.

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The crab is located about 6,500

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light-years away

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in the constellation Taurus.

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With this new full nebula image —

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the first in 25 years —

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we can compare the entire supernova

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remnant to itself over time

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and actually see it expanding.

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The supernova that created the Crab

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Nebula was recorded

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nearly 1,000 years ago as a “guest star”

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that was so bright

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it could even be seen during the day.

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Across the image, bright,

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threadlike strands

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are woven through the nebula.

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These are filaments —

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strands of supernova debris.

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As we look at Hubble's

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new highly detailed image

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compared to its earlier view,

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the nebula has clearly expanded.

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Over about 25 years,

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the Crab's filaments have moved outward

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(at a speed of around 3.4 million miles

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per hour!)

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The white haze

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diffused across

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the scene is synchrotron radiation,

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created by light

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from fast-moving

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particles interacting

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with magnetic fields.

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It's powered by a pulsar:

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the original star’s collapsed core,

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spinning incredibly fast

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and sending energy into the nebula.

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That's what makes the crab unusual.

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Its expansion is driven by a pulsar wind,

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rather than just riding

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the shockwave from the supernova.

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Focusing on the synchrotron glow

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reveals a subtle detail: shadows.

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Some filaments cast faint

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shadows onto the haze,

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which tells astronomers

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those filaments are sitting

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in front of the synchrotron emission.

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Others don't cast any shadows, suggesting

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they're embedded within,

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or behind the haze.

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Even though this is a flat,

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two dimensional image,

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those shadows give us clues

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to the crab's

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actual three-dimensional structure.

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The bright color palette displays

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the diversity of chemical elements

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in the nebula.

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Those different elements glow

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because they are being bathed in energy

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from the pulsar at the center.

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The Crab is the closest example

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of this type of supernova remnant

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that astronomers can study.

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Hubble is uniquely built for science

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like this.

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Decades of observations,

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plus the sharpness to compare

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them, lets us see and measure

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cosmic change.

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Hubble's new view becomes a benchmark —

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a snapshot scientists can return to again

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and again,

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building an even more complete picture

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of what a supernova leaves behind.