The Birth of Solar Systems
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The Birth of Solar Systems A solar system disk condenses and dissipates Collaps e of and interst ellar cloud Formation of a protostar and
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The Birth of Solar Systems. Formation of a protostar and disk. Collapse of and interstellar cloud. The disk condenses and dissipates. A solar system. The Birthplace of Stars. - PowerPoint PPT Presentation
Transcript of The Birth of Solar Systems
The Birth of Solar Systems
A solar system
The disk condenses and dissipates
Collapse of and interstellar cloud
Formation of a protostar and disk
The Birthplace of StarsThe space between the stars is not completely empty. Thin clouds of hydrogen and helium, seeded with the “dust” from dying stars, form in interstellar space.
Hot Stars make their Nurseries glow
The Orion Region InfraredOptical
Dark Clouds gather
Molecular CloudsSometimes (especially in spiral arms), the gas is compressed enough that the dust is thick and gravity can collapse knots in these “molecular” clouds to make new stars.
Where Stars Begin
A little bit of spin goes a long way…
Galactic shear and turbulence give every core a little spin (once round in 10 million years). But they get a lot smaller, and the spin goes up – to orbital!
It is for this reason that we believe there are many planetary systems – it is part and parcel of the star formation process to make a disk. Typical Galactic spin makes disks about the size of our Solar System…
The Sword of OrionThe nearest great stellar nursery to us is the great Orion molecular cloud which is about 1000 light years away, and manufacturing thousands of stars. This is probably how the typical
star is made.
The glowing tip of a molecular “cigar”
The Orion nebula is powered by 4 high mass luminous stars, which have cleared out their birthplace and are eating at a long cloud pointed at us.
The Trapezium
Near them, lower mass stars are forming
Hubble Space Telescope
They look like little windsocks
The blast from the luminous stars is eating away at the little guys
The heart of them contains a potential new solar system
“Proplyds” are new star-disk systems
Orion Proplyds
A whole cluster of new stars is born before us
Orion in the near infraredDisks in Orion
Hundreds of young stars, often with disks, have been seen.
The Star-Disk System Forms
And emits powerful bipolar jets
which extend for many light
years
negative image
The jet shocks are called Herbig-Haro Objects
Orion A
The jet is powered by the stellar magnetic
field and rotation, and takes away
excess angular momentum
piercing back out into the cloud
T Tauri Stars
The Young Star is Very Active
The magnetic flux is hundreds of times stronger than the Sun, and huge starspots are seen. The star itself is 3 times bigger.
The stage is set for planet formation
We see remnant disks around other stars
Star Formation is Beautiful, but ephemeral
Within about 10 million years, the birth-cloud is shredded, and the disks are dissipated. The process of starbirth has ended.
