Ad Astra
M☉ Notation
Unit of measurement in
astronomy called the solar mass.
- M stands for Mass
- ☉ Astronomical Symbol/Sun
- 1 M☉, Benchmark unit
- Equal to mass of our Sun
The Sun
(NASA/ESA)
Spirograph Nebula
(NASA/ESA)
Hourglass Nebula
(NASA/ESA)
O-Type Star
Star Classification: O
Luminosity Classification: V, III, I
Temperature (K) : 40000
Mass: 15–90 M☉ (main-sequence)
Elemental Composition: Hydrogen, Helium, trace ionized metals
Description: Extremely hot, massive blue stars above 25,000 K with intense ultraviolet radiation and short lifespans.
Birth: Collapse of massive, dense molecular cloud cores
Life: Extremely hot, bright, short-lived; rapid hydrogen fusion
☠️ Death: Explodes as a supernova
Reincarnation: Forms neutron stars or black holes
Example: Zeta Puppis, Theta¹ Orionis C
Luminosity Classes
Added to spectral types.
Indicates size & brightness:
- 0 or Ia+: Hypergiants
- I (Ia, Ib): Supergiants
- II: Bright Giants
- III: Regular Giants
- IV:Subgiants
- V: Main Sequence
- VI (sd): Subdwarfs
- D (VII): White Dwarfs
Galaxy in Orange
(Wiki Images)
Wolf-Rayet Star
(NASA/ESA)
Planetary Nebula (PN K 4-55)
(NASA/ESA)
