Linked Questions

14
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2answers
2k views

Could a satellite survive for thousands of years in a high enough orbit? [duplicate]

Let's suppose that an advanced alien civilization explored the Earth hundreds of thousands of years ago and then left a satellite in a high orbit, say of a radius of 100.000 km. Could such a ...
23
votes
5answers
5k views

Is there any limit to how many times you can increase velocity by repeated sling shot manoeuvres?

I believe travelling to Alpha Centauri at ~10 km/s would take of the order of 100 000 years (10 km/s is the order of speed of probes currently leaving the solar system). That seems 1. rather a long ...
11
votes
6answers
3k views

Can a satellite work like a radiometer?

Like a Crookes Radiometer, could a satellite have a stiff vain to maneuver? With a white side to let light pass and the black side capture light radiation be enough provide radiation pressure to keep ...
15
votes
6answers
24k views

Can an artificial satellite stay in orbit forever?

If an artificial satellite is in orbit around the Earth, it collides with dust and gas and loses a very small amount of kinetic energy to these collisions, and eventually will spiral down towards ...
29
votes
1answer
3k views

How is the Hubble main mirror protected from debris?

The Hubble Space Telescope recently hit 25 years in space. It orbits at ~550 km altitude (limited by the altitude the shuttle could reach to service it) and has sustained minor/trivial exterior ...
6
votes
5answers
1k views

Has anyone seriously considered a space-based time capsule?

It seems likely to me that with climate change, pandemics, economic downturns, nuclear or biological warfare that our civilisation could quite easily lose the ability to get into orbit. We could even ...
13
votes
1answer
3k views

What are these air-vent-like structures on this satellite?

I struck out with my previous question so I'll try again. What are these large circular 4-vane structures on the sides of NOAA-19 - the satellite that "fell down"? They remind me of adjustable air ...
8
votes
2answers
1k views

What is the current record for the farthest detection of a "dead" spacecraft?

In order to better defend my position that trying to track Juno from Earth once it can no longer transmit would be Quixotic, I'd like to ask what the current record is for the farthest detection from ...
13
votes
1answer
1k views

What is the principle behind Mariner 4's "Solar Pressure Vanes"? In what case(s) would they be effective?

The image below, found in this answer shows four "Solar Pressure Vanes" on Mariner 4. I've never heard of such a thing. I can imagine that it might have been thought to help favor the spacecraft's ...
2
votes
3answers
7k views

Can a smart phone function in space?

I recenty came a across a doubt... Can a smart phone be used in space? Obviously you aren't going to get any data signal, but will the functions like touch screen, GPS, accelerometer, vibrator, etc, ...
8
votes
1answer
2k views

What are these structures on the Lunar Ranging Retro Reflector (LRRR) arrays for?

In Local expansion measured, near zero via Lunar Ranging - what about deep space probes? I used images of the retro-reflector arrays that were left on the moon by Apollo 11, 14, and 15. The Lunar ...
5
votes
3answers
798 views

What is the typical relative impact velocity of orbital debris in low Earth orbit?

We all know that space is about going really fast. We also know that what matters in a collision isn't really absolute speed, but relative velocity. (Two cars with matched speeds on a highway touching ...
9
votes
2answers
225 views

Vacuum tube microchips for Venus probe; feasibility and challenges?

Venus surface temperature is around 460 °C which makes conventional semiconductors useless. So nasa proposed a clockwork rover, drawing power from wind and using springs and gears to navigate the ...
7
votes
1answer
271 views

What happens to satellites over a million years

I am curious to know what will happen to an average satellite over a 1 million year time span. Firstly, how high does the perigee need to be in order to not deorbit due to atmospheric friction ...
1
vote
1answer
547 views

Could Schiaparelli's retroreflector array (still) be used?

update 2: It appears Schiaparelli has already been located by satellite. This still represents the first laser ranging retroreflector array deployed beyond the Earth-Moon system! So assuming it is now ...

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