- 4138 - WHIRLPOOL GALAXY - with the James Webb telescope. The team behind that whirlpool portrait stated that "although Hubble is providing incisive views of the internal structure of galaxies such as M51, the planned James Webb Space Telescope is expected to produce even crisper images”.
--- 4138 - WHIRLPOOL GALAXY - with James Webb telescope.
- In 2011, scientists imaging M51 with Hubble
hoped to capture the galaxy with the JWST.
M51, also known as NGC 5194, lies about 27 million light-years away from
Earth in the constellation Canes Venatici, and is trapped in a tumultuous
relationship with its near neighbour, the dwarf galaxy NGC 5195.
- The Whirlpool galaxy is a dwarf galaxy
named NGC 5195. It is, in fact, partially because of this galactic interaction
that M51 may have such an ornate pattern in the first place.
-
- The gravitational influence of M51's
smaller companion is thought to be partially responsible for the stately nature
of the galaxy's prominent and distinct spiral arms. Those stunning spiral arms winding structure
dubs it a "grand-design" galaxy rather than just a standard spiral
galaxy.
-
- While a typical spiral galaxy exhibits
vortexed arms like M51 as well, grand-design spirals constitute about one-tenth
of all spiral galaxies and possess very strongly defined arms that stem from a
clear core region. It's technically up
for debate whether our Milky Way is a grand-design galaxy as well.
-
- To image M51, the JWST tapped into two of
its powerful infrared instruments: The Mid-Infrared Instrument and the
Near-Infrared Camera. This provided two separate perspectives on the galactic
subject (though there is a composite image that combines the two).
-
- Both devices are built to capture the
distant universe by decoding infrared light signals emanating from faraway
stars and galaxies. Once such signals manage to make their way to the
telescope's gold-plated, hexagonal mirrors, they're reflected onto the sensors
which can then parse the data for us.
Human eyes cannot see infrared light (we can only see visible light) and
so this machine is literally programmed to decode the invisible universe for
us.
-
- But what this means is, as with all JWST
images, both M51 portraits have been “colorized”. The dark red features in the NIRCam image
indicate warm filamentary dust in the realm while oranges and yellows show
spots of ionized gas that were spurred by recently formed star clusters. Stellar feedback has a dramatic effect on the
medium of the galaxy and creates complex networks of bright knots as well as
cavernous black bubbles.
-
- “Stellar feedback” refers to the way stars
pour energy into their surroundings, resulting in various processes that can
dictate things like the rate of formation for other budding stars.
-
- In the MIRI-centric image of M51, by
contrast, empty cavities and bright filaments appear to alternate, presenting
the impression of ripples propagating from the spiral arms. It also indicates a
much more dramatic filamentary structure in general when compared to the NIRCam
image. This is because certain light fragments associated with dust grains and
molecules "illuminate the cold gas of the galaxy."
-
- And putting both the MIRI and NIRCam images
together, scientists developed a composite photo that overlays all of those
remarkable nuances.
-
-
August 31, 2023 WHIRLPOOL GALAXY
4138
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