Direction in Space: Do We Launch Straight Up from the North and South Poles?

  • Context: High School 
  • Thread starter Thread starter elusiveshame
  • Start date Start date
  • Tags Tags
    Direction
Click For Summary

Discussion Overview

The discussion revolves around the concept of launching spacecraft from the Earth's poles versus the equator, particularly in relation to the orientation of the solar system and the energy costs associated with different launch trajectories. It explores the implications of these factors on space exploration and satellite deployment.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant notes that direction in space is relative and questions whether probes can be launched straight up from the poles, suggesting a lack of understanding of the implications of such launches.
  • Another participant explains that the plane of the solar system aligns with the Earth's equator, making sideways launches more practical for reaching other celestial bodies.
  • A different participant discusses the energy costs associated with launching in various directions, highlighting the fuel savings when launching satellites into orbits that align with the Earth's rotation and the solar system's ecliptic plane.
  • This participant also mentions that while polar orbits are used, launching towards the ecliptic is generally more efficient due to the proximity of most solar system bodies to this plane.
  • A later reply expresses gratitude for the explanations and indicates that the previous posts addressed all of their current questions.

Areas of Agreement / Disagreement

Participants generally agree on the technical reasons for launching along the ecliptic and the challenges associated with launching from the poles. However, the discussion does not reach a consensus on the feasibility or practicality of launching directly from the poles.

Contextual Notes

The discussion highlights the dependence on the orientation of the solar system and the Earth's rotation for efficient space travel, as well as the limitations of launching from locations with minimal infrastructure.

Who May Find This Useful

Individuals interested in space exploration, orbital mechanics, and the practical considerations of satellite launches may find this discussion relevant.

elusiveshame
Messages
170
Reaction score
35
If I understand correctly, direction in space is all relative to the observer (north, south, east, and west). Anyway, suppose we're looking at the Earth from a distance, where the north and south poles are located as on a globe.

My question is: when we send probes and shuttles into space, we seem to be going sideways for travel, but do we ever launch straight up from either of the poles and continue our exploration in other directions?

I do feel that I may not be understanding something, or missing something entirely. Any explanation or resources would be greatly appreciated.
 
Astronomy news on Phys.org
The plane of the solar system roughly corresponds to the plane of the equator of the Earth, this is why we launch things going out "sideways". If we launched something going "straight out of the poles" it wouldn't hit anything interesting for quite a long time as it would just be going away from the plane of the solar system and not towards other planets, etc. In addition, most of the people on Earth are located closer to the equator. There are no people at the poles, so it would be pretty hard to build launch sites there.
 
  • Like
Likes   Reactions: elusiveshame
The issue here is with the energy cost of sending anything into space in directions not coinciding with the rotation/revolution planes.

When you send a satellite into Earth orbit in the equatorial plane (the East-West plane) you can use the rotation of the planet to boost the satellite and save fuel.
The savings in terms of delta-V (the velocity required for a maneuver) are in the vicinity of 500m/s iirc. Compare with ~7 km/s required for a low-Earth circular orbit. It's not a whole lot, but still a substantial saving due to the way rockets work (you need extra fuel to move extra fuel and so on). But since it's not prohibitive either, we do sometimes send satellites into polar orbits.

With the solar system travel, the savings from the orbital velocity of Earth when sending probes in the ecliptic (orbital) plane amount to ~30km/s. Compare to about 45km/s required to escape the solar system from the distance of Earth's orbit. It's much, much easier to send stuff close to the plane of the ecliptic (which differs from equatiorial plane by 23.5 degrees by the way) and then try and alter the orbit with slingshot maneuvers.

But besides, almost everything in the solar system apart from some rare rocks lies within relatively few degrees from the ecliptic, so it's not like there's much reason to send stuff away in any other plane.
 
  • Like
Likes   Reactions: elusiveshame
Thank you both for the explanations, very helpful with imagining this and understanding why we launch along the ecliptic.

I was trying to think of any follow up questions, but it seems you both covered everything that I could think of at the moment :p
 

Similar threads

  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 23 ·
Replies
23
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K