Intersecting Orbits of Binary Stars: A Visual Guide

Click For Summary

Discussion Overview

The discussion revolves around the possibility of two stars in a binary system intersecting their orbits, particularly when the orbital plane is perpendicular to the observer's line of sight. Participants explore the conditions under which such intersections could occur, considering factors like mass, eccentricity, and the nature of the orbits.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that it is possible for two stars in a binary system to intersect their orbits.
  • One participant suggests that the orbits will intersect if the stars are similar in size and revolve around their center of mass.
  • Another participant elaborates that for orbits to intersect, the periapsis of the less massive body must be closer to the center of mass than the apoapsis of the more massive body, which depends on the mass ratio and eccentricity.
  • It is noted that while any mass ratio can theoretically allow for intersection with high enough eccentricity, the orbits may become hyperbolic rather than elliptical unless the masses are comparable.
  • Consideration is given to the need for accounting for the non-point mass nature of the bodies when discussing conditions for collision.
  • Links to simulations demonstrating the concept of intersecting orbits are provided by participants.

Areas of Agreement / Disagreement

Participants express varying opinions on the conditions necessary for orbit intersection, with no clear consensus on the specifics of those conditions. The discussion remains unresolved regarding the implications of mass ratios and eccentricities.

Contextual Notes

The discussion includes assumptions about the nature of the stars (point masses vs. non-point masses) and the mathematical conditions for orbit intersection, which may not be fully explored or agreed upon.

RingNebula57
Messages
56
Reaction score
2
Is it possible that 2 stars in a binary system to intersect their orbits like in this picture? ( the orbital plane is perpendicular to the line of sight)

stars 333.jpg
 
Astronomy news on Phys.org
My opinion is that they could
 
Since they are revolving around their center of mass, the orbits will intersect as long as the stars are similar in size.
 
mathman said:
Since they are revolving around their center of mass, the orbits will intersect as long as the stars are similar in size.
why?
 
RingNebula57 said:
why?
The orbits are coplanar, as they have to be in a 2-body interaction. As long as you can treat both bodies as point masses, the only condition for intersection is that the periapsis of the less massive body is closer to the centre of mass than the apoapsis of the more massive one. This depends on the combination of the ratio of masses and eccentricity.
In principle, this is achievable for any ratio of masses, as long as the eccentricity is high enough - but unless the two bodies are comparable in mass, the eccentricity is likely to be >1, i.e. the orbit will be hyperbolic rather than a closed ellipse.

If the bodies are not point masses, then conditions for collision need to be taken into account.
 

Similar threads

High School Question: Orbital mechanics of a binary star system
  • · Replies 5 ·
Replies
5
Views
3K
High School Does Sun cross planes of all binary stars?
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad Database of binary star data info within 10 PC of Earth
  • · Replies 5 ·
Replies
5
Views
3K
High School How Does a Massive Planet's Orbit Around the Sun Appear?
  • · Replies 6 ·
Replies
6
Views
2K
High School Question re binary star systems & possible orbits
  • · Replies 11 ·
Replies
11
Views
3K
Undergrad Why Do Stars in Binary Systems Assume a Teardrop Shape?
  • · Replies 14 ·
Replies
14
Views
2K
Undergrad Stable solutions to simplified 2- and 3-body problems?
  • · Replies 6 ·
Replies
6
Views
3K
Undergrad Early Catalog of Planet-Hosting Multiple Star (≥ 3) Systems
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad Star with quadrupole in a binary system violates Newton's 3rd Law?
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Is Tabby's Star a Binary System or an Alien Megastructure?
  • · Replies 22 ·
Replies
22
Views
6K