Travelling to Mars at constant velocity? Weightless?

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Discussion Overview

The discussion revolves around the concept of feeling weightless while traveling in a spaceship at a constant velocity towards Mars. Participants explore the conditions under which weightlessness occurs, particularly in relation to gravitational effects and the state of free-fall.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that traveling at a constant velocity (e.g., 10000 m/s) towards Mars may lead to a feeling of weightlessness, similar to astronauts in the ISS.
  • Others argue that the concept of being in orbit does not apply to a spacecraft traveling to another planet, raising questions about the nature of orbits and free-fall.
  • One participant states that being "not under power" is crucial for experiencing weightlessness, regardless of whether one is in orbit.
  • Another participant generalizes that any object not under power in space is in free-fall towards some gravitational body, though this may not always be evident.
  • Concerns are raised about the assumption of constant velocity during a trip to Mars, with some noting that velocity would not remain constant in free-fall.
  • A participant discusses the relationship between constant velocity, gravitational forces, and the sensation of weightlessness, suggesting that constant velocity implies a balance of forces.
  • Another participant questions the idea of feeling "pressured" while being weightless, emphasizing that maintaining constant velocity under gravity requires an opposing force.

Areas of Agreement / Disagreement

Participants express differing views on the conditions for weightlessness and the implications of constant velocity during space travel. There is no consensus on whether the same principles apply to a spacecraft traveling to Mars as to those in orbit.

Contextual Notes

Participants highlight the complexity of gravitational effects and the conditions under which weightlessness is experienced, indicating that assumptions about constant velocity and free-fall may not hold in all scenarios.

chi_rho
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If I'm traveling on a spaceship at a constant velocity (say 10000 m/s) towards Mars will I feel weightless, or will I feel nearly weightless because I will still be slightly affected by gravity?

I know that when astronauts are in the ISS they feel weightless because they are in a constant state of free-fall, but I don't feel like the same idea applies to the spaceship traveling to Mars. Any clarification would be great! Thanks!
 
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chi_rho said:
If I'm traveling on a spaceship at a constant velocity (say 10000 m/s) towards Mars will I feel weightless, or will I feel nearly weightless because I will still be slightly affected by gravity?

I know that when astronauts are in the ISS they feel weightless because they are in a constant state of free-fall, but I don't feel like the same idea applies to the spaceship traveling to Mars.
Why wouldn't it apply? They're still in orbit.
 
DaveC426913 said:
Why wouldn't it apply? They're still in orbit.

How are they still considered to be in orbit if they are traveling to another planet, not around? Can we consider anything traveling through space to be in an orbit of some type?
 
chi_rho said:
How are they still considered to be in orbit if they are traveling to another planet, not around? Can we consider anything traveling through space to be in an orbit of some type?
Not anything, just anything near the sun that is not under power.
 
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DaveC426913 said:
Not anything, just anything near the sun that is not under power.

Ok that makes sense! Thanks!
 
Although, it' not the 'in orbit' that makes them weightless, it's the 'not under power'.

If they were floating one jillion miles away in interstellar space, they'd effectively be stopped in space, not exactly in orbit, but they'd still be weightless.
 
I would generalize to say that any time you are not under power in space you are in free fall toward "something", it's just that "something" may not always be readily apparent.
 
russ_watters said:
I would generalize to say that any time you are not under power in space you are in free fall toward "something", it's just that "something" may not always be readily apparent.

During a trip to Mars the velocity wouldn't be constant in free fall.
 
DrStupid said:
During a trip to Mars the velocity wouldn't be constant in free fall.
True! Dave added the important qualifier, that "not under power" is the key state of affairs during a normal trip. Hopefully the OP now recognizes that "constant velocity" is an unusual condition to apply. I suspect he mistakenly believed that when coasting during a normal trip, velocity would be constant.
 
  • #10
I will be deviding you're question into 2, if you don't mind.

If you have constant velocity Then the added forced to you will be zero, even if gavity affects you, constant velocity means something is negating this gravity.
That means weightless (not massless). On the other hand you might feel presured by the forces.

On the other hand, In space, espacially on a trip to a different planet and in a solar system like ours, it is unlikely that if you feel significent force there will be something to negate it in space. So in a free fall to a planet you will change velocity, meaning acceleration . And that means force like F=ma using angular acceleration.

Hope I helped and not mislead, even though members here have deeper understanding of this subject.
 
  • #11
Spring said:
If you have constant velocity Then the added forced to you will be zero, even if gavity affects you, constant velocity means something is negating this gravity.
That means weightless (not massless). On the other hand you might feel presured by the forces.
How can you feel "pressured", but weightless? I'm not even sure what "pressured" means. Sorry, but maintaining constant velocity while under the influence of gravity requires applying a force opposite the gravitational force. A force you feel.
 

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