- 4331
- SMALLEST BROWN
DWARF STAR? James Webb telescope finds universe's
smallest 'failed star' in cluster full of mystery molecules. They have spotted what may be the smallest
known brown dwarf, a "failed star" that's only three or four times
larger than Jupiter.
-
----------------- 4331
- SMALLEST BROWN
DWARF STAR?
-
- Astronomers using the telescope (JWST) may
have identified the smallest star in the known universe. Or , at least, the smallest known object that
began forming like a star, before fizzling out as a ”brown dwarf”.
-
- One basic question you'll find in every
astronomy textbook is, what are the smallest stars? Using the JWST, they spotted the tiny
proto-star in a star cluster named “IC 348”, which is located 1,000 light-years
from Earth. The object is likely to be a brown dwarf, a type of celestial
object that blurs the line between planet and star.
-
- Brown dwarfs are not quite stars, but they
come close. Essentially, they are stars that failed to ignite, earning them the
unflattering nickname "failed stars." Brown dwarfs are not massive
enough to sustain typical hydrogen fusion in their cores.
-
- However, they do have enough mass to emit
light and heat from fusing a specialized type of hydrogen, called deuterium.
Deuterium is a stable form of hydrogen with an added neutron, whereas normal
hydrogen only has a proton in its nucleus.
-
- Most stars are incredibly dense compared to
even the biggest planets; our own sun is about 1,000 times the mass of Jupiter,
the largest planet in our solar system, but its diameter is only 10 times that
of Jupiter.
-
- In comparison, a large brown dwarf could
pack about 80 Jupiters inside. But this particular brown dwarf is only three or
four times more massive than Jupiter .
Easily making it the smallest "star," or star-like object,
ever discovered. It is also very young; the star cluster that it belongs to is
just 5 million years old.
-
- NASA's Cassini probe detected the same
molecular signature in the atmosphere of Saturn's moon Titan, but this is the
first time it has been seen outside of the solar system.
-
- In addition to being minuscule, the brown
dwarf and its neighbors appear to have an intriguing molecule floating around
in their atmospheres. The researchers detected a spectral signature from an
unidentified hydrocarbon, a molecule that contains some of the raw ingredients
for life as we know it.
-
- Models for brown dwarf atmospheres don't
predict its existence. We're looking at
objects with younger ages and lower masses than we ever have before, and we're
seeing something new and unexpected.
-
- Taken together, these observations could
help researchers paint a clearer picture of how stars form, and how they fail.
The researchers hope that future work will reveal even smaller stellar objects,
as well as any tiny true stars that may be hiding nearby.
-
-
January 27, 2023 SMALLEST
BROWN DWARF STAR? 4331
------------------------------------------------------------------------------------------
-------- Comments appreciated and Pass it on to
whomever is interested. ---
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for
copies or Index of all reviews
--- to:
------
jamesdetrick@comcast.net
------ “Jim Detrick” -----------
--------------------- --- Monday, January 29,
2024
---------------------------------
No comments:
Post a Comment