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| • |
Roberts
& Haynes 1994:
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– |
Masses
from S0 to Scd roughly constant, then decrease,
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and
M/L roughly the same (recall these are all
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primarily
luminous massive galaxies – why?)
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– |
H
I not significant in ellipticals (< 1 in 10000), but is in
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spirals
(0.01 to 0.15 from Sa to Sm)
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– |
Total
surface density decreases, H I surface density
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increases
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– |
Ellipticals
are red, spirals are blue…
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– |
H
II regions frequency increases monotonically along
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the
sequence (Kennicutt et al. 1989)
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| • |
Star
formation rates appear key to these relations
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