Do all planets, star, asteroids and other object have similar speed? Could we get hit by an object going the same speed as the sun (200km/s)?

339 viewsOtherPlanetary Science

Do all planets, star, asteroids and other object have similar speed? Could we get hit by an object going the same speed as the sun (200km/s)?

In: Planetary Science

4 Answers

Anonymous 0 Comments

Speed relative to what? Speed is only meaningful if it’s relative to something else. Also define what you mean my object? Are you only talking about large objects like celestial bodies? What about small particles?

Anonymous 0 Comments

It depends.

Speed is relative so what are you asking if they have speed relative to?

All speed is relative to something so this question is hard to answer with a reference point.

Anonymous 0 Comments

The good news is that most of the stuff around us was caught up in the formation of our solar system, so it’s going around the sun in the same direction as us and at similar speeds.

Most of the things that might intersect with the Earth would do so with a relative velocity of about 18 kilometers per second. That’s really, really fast, but not crazy fast. Even extrasolar objects tend to be things that were swept up in the same forces as us in the formation of the milky way, with a similar velocity.

But that isn’t everything. A rogue object ejected from another solar system could have tremendous relative velocity. Earth is rarely hit by charged particles with a velocity that is a signifgant percentage of the speed of light. Things like a rogue proton with the energy of a baseball thrown by a professional pitcher. These likely come from energetic stellar events like nova.

Anonymous 0 Comments

Most things in the solar system are going the same way since they’ve had billions of years to collude with things going the other way.

The larger objects in the solar system have mostly circular orbits. If anything is orbiting the sun in a circular orbit, anything else with that same radius of orbit will be going the same speed.

Due to this low relative speed, asteroids don’t hit the Earth at much more than escape velocity.

Only highly eccentric orbits would even be near something else traveling at a high relative speed (like a comet). These could hit the Earth at a much higher speed if conditions are right.

Something from outside the solar system is really the only candidate that could be traveling at such a speed.

Space is very empty, so the likelihood of anything traveling at such a high speed of hitting us is very unlikely.