Recycling in the Universe

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Recycling in the Universe

• Alyssa A. Goodman
• Department of Astronomy
• Harvard University

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Recycling on Earth In Galaxies
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Recycling in the Universe
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Making the First Recyclables...
Fluctuations about 300,000 years after the Big
Bang lead to Structure Formation.
Gravitational collapse of some of these
structures produces the first stars and
galaxies.
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Pretty young galaxies
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"Star Formation 101"
Molecular Cloud
Young Star with Outflow Protoplanetary Disk
Protostellar Core
Main Sequence Star (with Planets)
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Molecular Clouds The Stuff of New Stars
The Oschin telescope, 48-inch aperture
wide-field Schmidt camera at Palomar
Red Plate, Digitized Palomar Observatory Sky
Survey
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How much stuff is there?

• Star-counting
• Counts of stars per unit area measure how much
  material must be producing obscuration.

Observations by Alves, Lada Lada 1999
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Radio Spectral-line Observations of Molecular
Clouds
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How do Optical Radio Views Compare?
Region of Radio Spectral-Line Survey
Observations by Alves, Lada Lada 1999
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Cold, Dark Dusty

• Gas and Dust are Very Cold in Molecular Clouds,
  T10100 Kelvin
• Dust at 10 K Glows in the Far-Infrared

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Recycling in the Universe
Storage Collection in Interstellar Medium
Discarding
Processing, Production
Consumption
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Consumption of Recyclables
The "Initial Mass Function" (IMF)
The Hertzprung-Russell Diagram
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Stellar Recyclables
The Hertzprung-Russell Diagram
Spectacular contribution, and collection.
Explosion injects, and "sweeps up" interstellar
material.
Supernova, then neutron star/pulsar or black hole
Red giant then white dwarf
Good recyclables. Red-giant wind main dust
injection in ISM.
Long-lived brown dwarfs
"Styrofoam"
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Stellar Winds Discarding the RecyclablesMas
s100 x Sun
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"Excess Gas?" (Post-red-giant planetary nebula)
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Stellar Recyclables
The Hertzprung-Russell Diagram
Spectacular contribution, and collection.
Explosion injects, and "sweeps up" interstellar
material.
Supernova, then neutron star/pulsar or black hole
Red giant then white dwarf
Good recyclables. Red-giant wind main dust
injection in ISM.
Long-lived brown dwarfs
"Styrofoam"
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Massive Stars Supernovae

• Winds from O stars account for 30 of recylcable
  input to ISM
• Supernovae from O stars throw out much of the
  remaining mass
• Biggest contribution of (correlated) supernovae
  is to collection

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Swept-up GasThe Next Generation
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(At least) How much Gas is Swept-Up?
Warning Globe Readers Simple Algebra to Follow!
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Recycling in the Universe
Storage Collection in Interstellar Medium
Discarding
Processing, Production
Consumption
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Young Stars do Their Share Too
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One Picture with the Whole Story
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Recycling in the Universe(?)
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For more information...
cfa-www.harvard.edu/agoodman and Alyssa
Goodman's upcoming article in Sky Telescope
Magazine
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(Unusual?) Stellar Nursery in the Eagle Nebula
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Star Formation Caused by A Galaxy Collision
(a.k.a. igniting the trash)