- #1
randy23
- 14
- 0
Does a planet's atmosphere effect the temperature spacecraft s generate when descending from orbit?
Space shuttles descent temperatures
- Thread starter randy23
- Start date
-
- Tags
- Space
Click For Summary
Discussion Overview
The discussion revolves around the effects of a planet's atmosphere on the temperatures generated by spacecraft during descent from orbit. It explores theoretical aspects related to atmospheric composition, density, and their influence on heat generation and dissipation during re-entry.
Discussion Character
- Exploratory, Technical explanation, Debate/contested
Main Points Raised
- Some participants propose that the atmosphere has a minimal effect on a descending spacecraft, comparing it to a pebble thrown in a pond, suggesting that the impact is localized and short-lived.
- Others argue that the atmosphere significantly affects the temperature generated during descent, noting that heating is a function of the mean molecular mass and molecular density of the atmosphere.
- It is suggested that a denser atmosphere could lead to quicker deceleration and potentially greater heating rates on the thermal shield, with different atmospheric compositions (e.g., CO2 vs. N2 and O2) affecting the dynamics of descent.
- A participant mentions the need for detailed equations to quantitatively assess how atmospheric composition and density influence heat transfer rates and heat generation during descent.
Areas of Agreement / Disagreement
Participants express differing views on the extent of the atmosphere's effect on spacecraft temperatures during descent, indicating that multiple competing perspectives remain without a consensus.
Contextual Notes
The discussion lacks detailed quantitative analysis and specific equations to support claims, and assumptions regarding atmospheric effects are not fully explored.
- #2
Andre
- 4,296
- 73
Hi Randi and welcome.
Would you think that a pebble thrown in the pond will ripple the water for long? Likewise I don't think that the atmosphere will notice a lot of a descending space craft. Just a little bit, locally and very short.
The answer, my friend, is blowing in the wind.
Would you think that a pebble thrown in the pond will ripple the water for long? Likewise I don't think that the atmosphere will notice a lot of a descending space craft. Just a little bit, locally and very short.
The answer, my friend, is blowing in the wind.
- #3
Astronuc
Staff Emeritus
Science Advisor
Gold Member
2025 Award
- 22,620
- 7,639
Quite possibly is does if the heating generation and dissipation are functions of the mean molecular mass and molecular density of the atmosphere.randy23 said:
The heat is generated because a spacecraft is transfer its kinetic energy to the atmosphere. The energy is dissipated as a momentum transfer to atmosphere but also as heat in the heat shield, which may be primarily by radiation.
Presumably a denser atmosphere can slow a spacecraft more quickly than a thin atmosphere, and perhaps would produce a greater heating rate on the thermal shield. A predominantly CO2 atmosphere would give a different deceleration than the Earth's atmosphere of N2 and O2 all else the same. Unfortunately, I don't have any detailed equations, so I can't answer the question quantitatively. One would have to know how the atmospheric composition and density affect the radiative and conductive heat transfer rates, well as the heat generation rate.
- #4
randy23
- 14
- 0
Andre said:
Thanks, it's nice to be here.