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)
Red Giant
Star Classification: K-M
Luminosity Classification: III
Temperature (K) : 3300
Mass: 0.3–8 M☉ (low or intermediate mass)
Elemental Composition: Hydrogen, Helium, carbon, nitrogen, oxygen
Description: Evolved stars that have exhausted core hydrogen and expanded into large, cool, luminous giants.
Birth: Former main-sequence star expanding after hydrogen depletion
Life: Large, cool, luminous; helium fusion begins
☠️ Death: Planetary nebula
Reincarnation: White dwarf
Example: Aldebaran, Arcturus
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)
