3 ms·
It's not universal anyway. Different stars orbit at different periods. The difference might not be large, but I am not sure you can really define a "galactic
by adrianratnapala 10y ago
It's not universal anyway. Different stars orbit at different periods. The difference might not be large, but I am not sure you can really define a "galactic year" with much precision.
- Tepix 10y agoWikipedia has this to say about the rotational speed of the milky way: "Stars and gases at a wide range of distances from the Galactic Center orbit at approximately 220 kilometers per second. The constant rotation speed contradicts the laws of Keplerian dynamics and suggests that much of the mass of the Milky Way does not emit or absorb electromagnetic radiation. This mass has been given the name "dark matter".[34] The rotational period is about 240 million years at the position of the Sun."
- adrianratnapala 10y agoYes. If they all go at the same speed (linear, in km/s) that means they all have different angular velocities, i.e. stars near the centre will have shorter period. That's why the article specified the period as about 240Myr at the position of the Sun.
- Wintamute 10y agoNobody is talking about a "standard" galactic year apart from you as far as I can gather ... it's just about the specific orbital period of our sun. The parent of your reply is talking about using more universal units, not trying to define a universal galactic year.