Can S5-HVS1 Retain Its Planets?

  • Context: Undergrad 
  • Thread starter Thread starter DavidCummings
  • Start date Start date
  • Tags Tags
    Planets
Click For Summary
SUMMARY

Astronomers have identified the ultrafast star S5-HVS1, which travels at 6 million km/h and was ejected from the Milky Way's supermassive black hole five million years ago. The discussion centers on whether S5-HVS1 could retain any planets during its ejection. Gravitational slingshots, as utilized by NASA, suggest that the planets likely diverged from their original orbits due to the extreme velocities involved. The calculations indicate that while S5-HVS1 is moving significantly faster than the Sun, it is plausible that it could retain planets up to the orbit of Saturn.

PREREQUISITES
  • Understanding of gravitational slingshot mechanics
  • Familiarity with stellar dynamics and orbital mechanics
  • Knowledge of the Milky Way's supermassive black hole, Sag A*
  • Basic astrophysics concepts related to velocity and acceleration
NEXT STEPS
  • Research the mechanics of gravitational slingshots in astrophysics
  • Study the dynamics of supermassive black holes and their effects on surrounding stars
  • Explore the characteristics and behavior of hypervelocity stars
  • Investigate the potential for exoplanets around high-velocity stars
USEFUL FOR

Astronomers, astrophysicists, and space enthusiasts interested in stellar dynamics, hypervelocity stars, and the implications of gravitational interactions in the Milky Way.

DavidCummings
Messages
5
Reaction score
5
TL;DR
If S5-HVS1 ever had planets, would they all get stripped off when the star was ejected from the galaxy?
"Astronomers have spotted an ultrafast star [S5-HVS1], traveling at a blistering 6 million km/h, that was ejected by the supermassive black hole at the heart at the Milky Way five million years ago." -- https://www.sciencedaily.com/releases/2019/11/191112110238.htm

If this star had planets 5 million years ago, when it began its "blistering" journey, could it have held on to any of those planets, or would they all have been stripped off at the time of ejection?

Thanks.
 
Astronomy news on Phys.org
Gravitational slingshots produce fairly precise trajectories based on the gravity of the body doing the slingshotting and the closeness of the passby. NASA has made very precise use of this fact. Given the rather extreme results of this apparent event, I would think it likely that the planets would have had enough of a different distance to result is a slightly different trajectory that would likely have caused them to diverge, subsequently, from their sun.
 
I disagree with phinds. It's going fast, but not crazy fast: about 7x faster than the sun. The star making the closest approach to Sag A* is called S2, traveling 3x faster than that. Just ballparking it, that means a closest approach of around 7 light days and an acceleration of 1.5 x 10-2 m/s2. An earth-like orbit is at 8 light minutes, so the differential acceleration is ~10-5 m/s2. This is much smaller than the actual acceleration of 6 x 10-3 m/s2.

You're probably OK up to the orbit of Saturn or so.


 
  • Like
Likes   Reactions: Dragrath and phinds

Similar threads

  • · Replies 142 ·
5
Replies
142
Views
137K
  • · Replies 19 ·
Replies
19
Views
4K
  • · Replies 5 ·
Replies
5
Views
5K