Sternmodell
Technical information
Model size and coordinate system:- Model volume: 1000 pc3 = 34 646 Ly3
- Edge length of the model: 10 pc = 32.6 Ly
- Radius of inner circle of equatorial system: 1 pc = 0.307 Ly
- Radius of outer circle of equatorial system: 3.07 pc = 10 Ly
- Half-length of diagonal (max. distance from Sun): 8.66 pc = 28.2 Ly
Number of stars in model:
- A dwarfs: 2
- F dwarfs: 2
- G dwarfs: 4
- K dwarfs: 9
- M dwarfs and brown dwarfs: 92
- White dwarfs: 5
- All stars: 114
Observations:
- One of the M dwarfs is an erroneous entry in the Hipparcos catalog (HIP 114110).
- The star census is very incomplete for Brown dwarfs.
- We originally thought that the star census is also incomplete for M dwarfs.
- Especially the corners of the volume seem to lack stars, and we thought that there may be a number of M dwarfs which are too faint for Hipparcos parallax measurements.
- However, all so far available GAIA data releases (from the TGAS to the eDR3 catalogs) have not added any more stars; so it looks like the model is complete for M dwarfs.
- Many of the stars are actually binary systems, which are so narrow that they cannot be represented here.
- This is a model:
- all stars are too big,
- space is much emptier than represented here,
- the relative sizes of the stars are approximate, at best,
- the brightness differences are in reality much, much larger.
- All stars are close to the main-sequence or, in 5 cases, white dwarfs.
- There are no giant stars, which would completely dominate the picture.
- The fact that there are a few stars after the giant phase, the 5 white dwarfs, but no giants is an indication that the giant phase is a short episode in the life of a star.
The model is on loan from the Max-Planck-Institut für Astronomie in Heidelberg. 