<p>Looking at the diagram as a whole, the bottom line seems to be the type of object that a star in that category will evolve into.  So a large star that is variable due to mass loss will explode in a type II SN and evolve to either a Black Hole, or a Neutron star (which may become variable as a pulsar but ultimately evolves to a non variable NS.</p>
<p>Looking down the right. We see &quot;mass exchange variables (ie novae) and dwarf novae such as U Gem or Z And will ultimately evolve into one of three types of stellar remnant: Black dwarfs, neutron stars or black holes. Black dwarfs are the final stage of evolution of white dwarfs.</p>
<p>Therefore I surmise that BD means Black Dwarf.</p>

CC BY-SA 4.0
2020-11-09T13:36:13.843Z
2020-11-09T13:36:13.843Z
James K
<p>The one in the sector as BD/NS/BH. And please explain why Brown/Black dwarf should be here among neutron stars and black holes. Thank you for your help.</p>
<p><a href="https://i.sstatic.net/1o67u.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/1o67u.jpg" alt="enter image description here" /></a></p>
<p>Source: Beech, M. (2019). <a href="https://link.springer.com/book/10.1007/978-3-030-11704-7" rel="nofollow noreferrer">Introducing the stars</a>. Cham: Springer Nature Switzerland AG.</p>

CC BY-SA 4.0
2020-11-09T11:52:33.800Z
Can you credit the original source for the diagram? Thanks!
uhoh
<dwarf-star>
Should BD in this sector means Brown dwarfs or Black dwarfs?
Jack the Ranger
# Should BD in this sector means Brown dwarfs or Black dwarfs?

(Asked by: username_0 on 2020-11-09)

The one in the sector as BD/NS/BH. And please explain why Brown/Black dwarf should be here among neutron stars and black holes. Thank you for your help.

[![enter image description here](https://i.sstatic.net/1o67u.jpg)](https://i.sstatic.net/1o67u.jpg)

Source: Beech, M. (2019). [Introducing the stars](https://link.springer.com/book/10.1007/978-3-030-11704-7). Cham: Springer Nature Switzerland AG.

**Tags:** dwarf-star
> **Comments:**
> **username_1**: Can you credit the original source for the diagram? Thanks!  

---

## 1 answers

### Answer by username_2 on 2020-11-09. Score: 2 | Accepted answer

Looking at the diagram as a whole, the bottom line seems to be the type of object that a star in that category will evolve into. So a large star that is variable due to mass loss will explode in a type II SN and evolve to either a Black Hole, or a Neutron star (which may become variable as a pulsar but ultimately evolves to a non variable NS.

Looking down the right. We see "mass exchange variables (ie novae) and dwarf novae such as U Gem or Z And will ultimately evolve into one of three types of stellar remnant: Black dwarfs, neutron stars or black holes. Black dwarfs are the final stage of evolution of white dwarfs.

Therefore I surmise that BD means Black Dwarf.


---

