NASA's Hubble Space Telescope has been
observing the Crab Nebula for decades.
The crab is located about 6,500
light-years away
in the constellation Taurus.
With this new full nebula image —
the first in 25 years —
we can compare the entire supernova
remnant to itself over time
and actually see it expanding.
The supernova that created the Crab
Nebula was recorded
nearly 1,000 years ago as a “guest star”
that was so bright
it could even be seen during the day.
Across the image, bright,
threadlike strands
are woven through the nebula.
These are filaments —
strands of supernova debris.
As we look at Hubble's
new highly detailed image
compared to its earlier view,
the nebula has clearly expanded.
Over about 25 years,
the Crab's filaments have moved outward
(at a speed of around 3.4 million miles
per hour!)
The white haze
diffused across
the scene is synchrotron radiation,
created by light
from fast-moving
particles interacting
with magnetic fields.
It's powered by a pulsar:
the original star’s collapsed core,
spinning incredibly fast
and sending energy into the nebula.
That's what makes the crab unusual.
Its expansion is driven by a pulsar wind,
rather than just riding
the shockwave from the supernova.
Focusing on the synchrotron glow
reveals a subtle detail: shadows.
Some filaments cast faint
shadows onto the haze,
which tells astronomers
those filaments are sitting
in front of the synchrotron emission.
Others don't cast any shadows, suggesting
they're embedded within,
or behind the haze.
Even though this is a flat,
two dimensional image,
those shadows give us clues
to the crab's
actual three-dimensional structure.
The bright color palette displays
the diversity of chemical elements
in the nebula.
Those different elements glow
because they are being bathed in energy
from the pulsar at the center.
The Crab is the closest example
of this type of supernova remnant
that astronomers can study.
Hubble is uniquely built for science
like this.
Decades of observations,
plus the sharpness to compare
them, lets us see and measure
cosmic change.
Hubble's new view becomes a benchmark —
a snapshot scientists can return to again
and again,
building an even more complete picture
of what a supernova leaves behind.