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The places where stars and planets are born are among the galaxy's most beautiful locales.
These cosmic landscapes change as new generations of stars light up and disperse their birth
cloud. But the youngest stars seen here are already perhaps a million years old, hardly
toddlers.
Stars and planets form in the dark, inside vast cold clouds of gas and dust, such as
these pillars imaged by the Hubble Space Telescope.
The dust is so thick we can't see the infant stars inside, at least not with visible light.
With infrared light, Hubble can see through all but the thickest dust. Yet it's in those
dense knots that the youngest stars are forming.
To peer inside them, astronomers need the James Webb Space Telescope. With a mirror
larger than Hubble's, and performance optimized for the infrared, Webb will give astronomers
their closest look yet at stellar birth.
We're flying through a computer model that represents astronomers best ideas about the
star formation process.
Reddish area indicate thicker dust, the temperature less than 400 degrees below zero Fahrenheit.
Or less than 240 degrees below zero Celsius.
That pinwheel ahead is a protostar, perhaps 10,000 years old. Protostars arise when a
dense knot of dust, less than a light year across, collapses. But the details of the
process are not well known. Elsewhere in the cloud, another protostar is preparing to build
planets. As the star that created the protostar collapsed, it flattened into a disk. The disk
we see here is 600 times the Earth's orbit around the Sun.
If placed in our solar system, it would extend far beyond the planets.
In this computer model, the disk continues to accumulate gas and dust from its surroundings
for thousands of years. Eventually the disk fragments, producing dense, bright structures.
These may become sites where giant planets form.
Later, during another phase of construction, smaller, Earth-sized planets may take shape.
At least that's what scientists think happens in the cold heart of stellar nurseries.