Space Science with Python #6: The Solar System Barycentre
Kepler found 3 major laws that describe the movement of objects in the Solar System. But are they “100 %” correct?
400 years ago, Johannes Kepler used tons of astrometric data of planets to determine that the geo-centric system had severe flaws… and that the world we live in is probably helio-centric (so Sun “focused”).
Based on his observations and data tables he stated 3 laws, known nowadays as the Kepler’s laws of planetary motion. They state the following (from the corresponding wiki page):
- The orbit of a planet is an ellipse with the Sun at one of the two foci.
- A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.
- The square of a planet’s orbital period is proportional to the cube of the length of the semi-major axis of its orbit.
Based on the first law, the Sun is the absolute centre of the Solar System and that all bodies revolve around it. Later however, Sir Isaac Newton stated that all bodies have a gravitational attraction. Consequently, the planets, asteroids and even the dust particles that cause meteors have a gravitational pull. And this pull affects also the Sun.
Sure, 99 % of the Solar System’s mass is gathered in the spheric Hydrogen / Helium — Ball we call the Sun. But the remaining 1 % … do they influence the position and movement of our centre star?
To answer this question we use, again, Python and NASA’s SPICE toolkit to dive into this space scientific question; in tutorial video #6:
As always, the corresponding code can be found on GitHub:
Stay tuned for more short summaries of the already present tutorial video and future tutorials that will come up, soon. Feel free to comment and ask any questions either here or on Twitter.
Thomas
