Science
The James Webb telescope found hundreds of 'little red dots' in the ancient universe. We still don't know what they are.
Astronomers exploring the faraway universe with the James Webb Space Telescope, NASA's most powerful telescope, have found a class of galaxies that challenges even the most skillful creatures in mimicry — like the mimic octopus. This creature can impersonate other marine Animals to avoid predators. Need to be a flatfish? No problem. A sea snake? Easy.
When astronomers analyzed the first Webb images of the remote parts of the universe, they spotted a never-before-seen group of galaxies. These galaxies — some hundreds of them and called the Little Red Dots — are very red and compact, and visible only during about 1 billion years of cosmic history. Like the mimic octopus, the Little Red Dots puzzle astronomers, because they look like different astrophysical objects. They're either massively heavy galaxies or modestly sized ones, each containing a supermassive black hole at its core.
However, one thing is certain. The typical Little Red Dot is small, with a radius of only 2% of that of the Milky Way galaxy. Some are even smaller.
As an astrophysicist who studies faraway galaxies and black holes, I am interested in understanding the nature of these little galaxies. What powers their light and what are they, really?
The mimicking contest
Astronomers analyze the light our telescopes receive from faraway galaxies to assess their physical properties, such as the number of stars they contain. We can use the properties of their light to study the Little Red Dots and figure out whether they're made up of lots of stars or whether they have a black hole inside them.
Light that reaches our telescopes ranges in wavelength from long radio waves to energetic gaMMA rays. Astronomers break the light down into the different frequencies and visualize them with a chart, called a spectrum.
Related: Can the James Webb Space Telescope see galaxies over the universe's horizon?
-
Science5h ago
Which animals are evolving fastest?
-
Science6h ago
Scientists finally know why ultraviolent superstorms flare up on Uranus and Neptune
-
Science6h ago
Monster black hole is starving its host galaxy to death, James Webb telescope reveals
-
Science11h ago
'Completely unexpected': New type of wood discovered by scientists dubbed 'midwood'
-
Science22h ago
Fall equinox 2024: When it is, why it happens and what to look for
-
Science22h ago
A long-lost moon could explain Mars' weird shape and extreme terrain
-
Science1d ago
Polaris Dawn Sets New Space Altitude Record—and There’s More to Come
-
Science1d ago
Greenhouse gas 80 times more potent than CO2 is rising in the atmosphere — and fast