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Questions tagged [energy]

Questions addressing the energy requirement for space/orbit/interplanetary missions.

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Solar panels on Mars?

I was wondering if a base on Mars could be powered by solar energy alone? Since Mars is further away from the Sun wouldn't that mean lower efficiency thus making solar not scalable? Let's assume a ...
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Would a flywheel energy storage have a distinct advantage or disadvantage in zero or low gravity?

The Centrifugal Battery (flywheel as an energy storage device) has been around [a while]since at least 1857. This comment and geoffc's answer (batteries and Bearings) got me wondering what would the ...
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1answer
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What is the “launch energy” or C₃ measured in km² / s²

In some papers there is "launch energy" characteristic of spacecraft launched into space from Earth. Sometimes it is written as "C₃" (C3). For example, Ares V document lists "C₃" as equal or less than ...
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Does the ISS need more heating or more cooling?

While reading the recent question 'Do exercise machines on the ISS generate electric energy?', I got thinking all of the exerciser machines generate heat (heat energy). So yes all exercise machine ...
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Why are Ion Thrusters so energy hungry?

Ion thrusters need a lot of energy. But I don't understand why. So, one thing I understand is that it takes a lot of energy to achieve a high exhaust velocity ( since kinetic energy is proportional to ...
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2answers
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What types of sustainable energy are available beyond Mars?

Most of the energy we use on Earth in our daily activities is a derivative of solar; wind, hydroelectric, coal, gas (oil), wood fire, solar cells. While we might not think about it, all of these are ...
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How much Energy is required to put 1 kg in LEO?

I was wondering, what is the minimum amount of energy required to put 1 kg of payload into LEO?
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1answer
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How do you slow down a solar sail?

From what I understand, a lot of the difficulty in using conventional rockets to move payloads to other planets is that the object needs to lose its velocity one way or another so it doesn't slam into ...
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4answers
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Is wind-power a viable backup power source for Mars One?

A question related to What power source options provide reliable and sustainable power generation for a Martian Colony, particularly the answer that solar and nuclear based energy sources being the ...
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Methods for propulsion other than rockets for leaving Earth's atmosphere?

Due to the large amount of energy required, the standard method for leaving the Earth's atmosphere is rocket propulsion. Is there any other methods in development that don't involve rockets? E.g. ...
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2answers
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How far from the Sun can solar power be used as a reliable energy source?

Space probes headed for the far reaches of our Solar System rely on radioisotope thermoelectric generators for power (Cassini–Huygens, Voyager 1, Voyager 2). Presumably this is because solar power ...
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1answer
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Escape velocity for our galaxy

What should be the escape velocity for our galaxy and can we calculate it? For instance, if we assume that we don't know the mass of our galaxy, you may consider it as small 'm'.
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Do any realistic rocket systems use different substances for propellant and fuel?

In his Edge.org Annual Question response, Progress in Rocketry, George Dyson exults in the success of Blue Origin and SpaceX in landing their rockets after pushing them past the Kármán line, and then ...
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Could Earth-lunar flybys be repeated consecutively without the use of propellant?

Ever since a recent orbital mechanics question, lunar flybys have been nagging me in the sense that there is obviously energy available in the system. I'm interested if you could get a repeatable ...
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How much energy is required to send a payload of 40 t from Earth's surface to LEO?

I am confused with energy requirement equations... Am I anywhere near with my following assumptions: $\Delta v$ from surface to LEO is 9000 m/s typical exhaust velocity $v_e$ = 4500 m/s and mass of ...
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Never reducing propellant for space propulsion [closed]

In this sketch there is a gun system as a propellant chamber and we are using iron balls as a propellant. An electromagnet is attached on the other side of this engine .When we fire these Iron ...
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3answers
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Splitting water quickly to turn a water rocket into a H/O rocket at launch: could it work?

I was just looking at a small but impressive compressed air/water rocket that launches off of a metal rod that runs through the nozzle and spans 3/4 of the length of the rocket. As the team increased ...
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2answers
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What is the status of concentrated solar energy (CSE) in space exploration?

The Cassini Environmental Impact Statement, Chapter 2 (page 53–54) describes the status of Concentrated Solar Energy in space: A 1981 conceptual study of the system impacts of using a concentrated ...
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1answer
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Practical Lunar He-3 mining approach?

There is a lot of popular talk that There may be huge deposits of Helium-3 on the Moon, and It could be used for very efficient fusion reactors. Unfortunately in the bulk of popular talk actual ...
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1answer
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How efficient would it be for an outpost to use human-powered vehicles?

Considering how bicycles use human power very efficiently for transport, would it be reasonable for astronauts on an outpost on the Moon or Mars to use easily replaceable human-powered equipment, like ...
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3answers
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About how long will Curiosity last on its nuclear power?

Curiosity, we know, has no little nuclear reactor, it has a RTG. Great! But how long will it last? For how many years will our little 1-ton friend be roaming around another planet?
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Would geothermal energy be practical on a lunar base?

Given sufficient liquid in the form of water or other suitable medium, would the use of geothermal energy be practical or feasible for powering a lunar colony? Wikipedia (referenced) gives an ...
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686 views

Could thermal energy be collected by dragging a thermoconductive device against the outer atmosphere

Atmospheric reentry is notoriously a difficult and HOT endevour. Could this thermal energy be used as an alternative energy source on earth? Could this be used through some sort of orbital charging ...
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Dissipating large amounts of energy fast, in space

Currently, we have good methods of sustained, slow dissipation of energy through radiators. They take quite large area (and mass) per watt dissipated though. I know sublimators were used at least in ...
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Do (Or can) satellites help renewable energy companies? [closed]

Renewable energy, such as wind, solar, and geothermal, can sometimes be difficult to find optimal locations for. How are, or can, satellites be used to assist in finding the optimal locations for ...
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Power to grow food per person

Can I get a rough estimate of the power (in watts) needed to produce light to grow enough food for one person, using vertical farming of the kind proposed for space habitats? Any reasonable outpost/...
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2answers
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In space can the difference in temperature between the inside and outside, provide useful energy?

The Thermoelectric effect allows for electrical energy to be created, based on a difference of temperature. In fact the Radioisotope thermoelectric generator is based on this principal and does/has ...
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1answer
2k views

Can we get energy from the motion of orbiting bodies?

Can we convert the motion energy of bodies (such as satellites) moving around a high-gravity objects (like Earth or the Sun) to some kind of usable energy?
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3answers
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Will space-based energy beamed to earth increase heat on earth?

A Japanese paper on beaming energy from solar installation on the moon to earth via laser and microwave recently made the rounds in the media. Would this, or any space-based energy system cause a net ...
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2answers
291 views

Solar Flux on Mars Surface

Considering that the Solar Flux on top of Mars' atmosphere is 590 W/m2 (following the 1/r^2 relation for sunlight), how much of this incident light actually arrives to Mars. In other words, what is ...
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1answer
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How feasible is wind energy generation on Mars? [duplicate]

Spacecrafts and rovers tend to have dust settled on their panel which leads to reduced power generation. If wind turbines could power the instruments, then the seasonality of solar power generation ...