Young stars are rambunctious!
NASA’s James Webb Space Telescope
has captured the “antics” of a pair of actively forming young stars, known as
Herbig-Haro 46/47, in high-resolution near-infrared light. To find them, trace
the bright pink and red diffraction spikes until you hit the center: The
stars are within the orange-white splotch. They are buried deeply in a disk of
gas and dust that feeds their growth as they continue to gain mass. The disk is
not visible, but its shadow can be seen in the two dark, conical regions
surrounding the central stars.
The most striking details are the
two-sided lobes that fan out from the actively forming central stars,
represented in fiery orange. Much of this material was shot out from those
stars as they repeatedly ingest and eject the gas and dust that immediately
surround them over thousands of years.
When material from more recent
ejections runs into older material, it changes the shape of these lobes. This
activity is like a large fountain being turned on and off in rapid, but random
succession, leading to billowing patterns in the pool below it. Some jets send
out more material and others launch at faster speeds. Why? It’s likely related
to how much material fell onto the stars at a particular point in time.
The stars’ more recent ejections appear in a
thread-like blue. They run just below the red horizontal diffraction spike at 2
o’clock. Along the right side, these ejections make clearer wavy patterns. They
are disconnected at points, and end in a remarkable uneven light purple circle
in the thickest orange area. Lighter blue, curly lines also emerge on the left,
near the central stars, but are sometimes overshadowed by the bright red
diffraction spike.
All of these jets are crucial to
star formation itself. Ejections regulate how much mass the stars ultimately
gather. (The disk of gas and dust feeding the stars is small. Imagine a band
tightly tied around the stars.)
Now, turn your eye to the second
most prominent feature: the effervescent blue cloud. This is a region of dense
dust and gas, known both as a nebula and more formally as a Bok
globule. When viewed mainly in visible light, it appears almost
completely black –
only a few background stars peek through. In Webb’s crisp near-infrared image,
we can see into and through the gauzy layers of this cloud, bringing a lot more
of Herbig-Haro 46/47 into focus, while also revealing a deep range of stars and
galaxies that lie well beyond it. The nebula’s edges appear in a soft orange
outline, like a backward L along the right and bottom.
This nebula is significant – its
presence influences the shapes of the jets shot out by the central stars. As
ejected material rams into the nebula on the lower left, there is more
opportunity for the jets to interact with molecules within the nebula, causing
them both to light up.
There are two other areas to look
at to compare the asymmetry of the two lobes. Glance toward the upper right to
pick out a blobby, almost sponge-shaped ejecta that appears separate from the
larger lobe. Only a few threads of semi-transparent wisps of material point
toward the larger lobe. Almost transparent, tentacle-like shapes also appear to
be drifting behind it, like streamers in a cosmic wind. In contrast, at lower
left, look beyond the hefty lobe to find an arc. Both are made up of material
that was pushed the farthest and possibly by earlier ejections. The arcs appear
to be pointed in different directions, and may have originated from different
outflows.
Take another long look at this
image. Although it appears Webb has snapped Herbig-Haro 46/47 edge-on, one side
is angled slightly closer to Earth. Counterintuitively, it’s the smaller right
half. Though the left side is larger and brighter, it is pointing away from us.
Over millions of years, the stars
in Herbig-Haro 46/47 will fully form – clearing the scene of these fantastic,
multihued ejections, allowing the binary stars to take center stage against a
galaxy-filled background.
Webb can reveal so much detail in
Herbig-Haro 46/47 for two reasons. The object is relatively close to Earth, and
Webb’s image is made up of several exposures, which adds to its depth.
Herbig-Haro 46/47 lies only 1,470
light-years away in the Vela Constellation.
The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.
Source: Webb
Snaps Highly Detailed Infrared Image of Actively Forming Stars | NASA
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