Birth and Death of a StarBirth and Death of a Starand planetary systemsand planetary systems

We’ve got the Hydrogen and We’ve got the Hydrogen and Helium, now lets turn them on Helium, now lets turn them on

and let them Go!and let them Go!

Cosmic AbundancesCosmic Abundances

HydrogenHydrogen• 80%80%

HeliumHelium• 20%20%

LithiumLithium• TraceTrace

BerylliumBeryllium• TraceTrace

All that gasAll that gas

Anything with mass has gravityAnything with mass has gravity

Clumps of gas (the Big Bang wasn’t Clumps of gas (the Big Bang wasn’t exactly smooth) began to fall exactly smooth) began to fall togethertogether

Dust and gas Dust and gas region – The region – The Horsehead Horsehead Nebula (in Nebula (in Orion)Orion)

Dust Dust Clouds Clouds with with stars stars forming forming insideinside

Dust Dust around around a star – a star – a solar a solar system system formsforms

Proto- Proto- planetary planetary disks - disks - stars stars forming forming planetsplanets

In M42In M42

The disk The disk flattens, gas flattens, gas and dust and dust comes comes together. together. The star is The star is ONON

Star Birth behind dust – M42Star Birth behind dust – M42

Once they Once they turn on, turn on, stars push stars push the gas and the gas and dust away.dust away.

Same beginnings – different focusSame beginnings – different focus

Lets do a short focus on the Lets do a short focus on the planetary system formation.planetary system formation.

We’ll be discussing the planets in We’ll be discussing the planets in more depth later.more depth later.

The Condensation SequenceThe Condensation Sequence

Radar Radar study of study of an an asteroid asteroid going by.going by.