# All Questions

9,721 questions
139 views

### What's the shiny triangular feature on this Progress vehicle?

Picture from here What's the shiny, slightly curved triangular plate with rails above it? A larger version, cropped from here, thanks to a comment by ohsin.
72 views

### How do you calculate the lat and lon of a point on the earth using azimuth and elevation seen from a geostationary satellite?

I am given the longitude of a geostationary satellite and a pointing vector from the satellite in the form of azimuth and elevation angles looking from the satellite towards the earth (where zero ...
3k views

### Qualitative differences between gravity and a spinning habitat

I'm aware that living in a spinning habitat has a couple of noticeable differences from being on terra firma. For instance, running in the direction of the spin ought to make you feel heavier, while ...
74 views

### What is the effect of a solar flare on electronics on the surface of Mars?

Mars has practically no magnetosphere. Where does the impact of a solar flare on the electronics of Mars landers and rovers fall along the scale of nothing to EMP?
59 views

### Would be some sort of cloud software required in a space colony? [closed]

This is very hypothetical but still hard and not vague theoretic question I think: would future space colonies use some sort of network and hardware virtualization?
1k views

### Why latest Landsat satellites have solar panel on only one side?

It is normal for satellites to have solar panels on both sides of the body. But Landsat satellites, from Landsat 4, seems to have the solar panel on only one side. Are there any specific advantages ...
121 views

### What's the role of the chainmail and scale armor on InSight's WTS?

It's like taken directly from a medieval armor... The role of wind and thermal shield (WTS) deployed over the seismometer is in its name - protecting it from noise and thermal changes. This is fairly ...
193 views

### Why do the ISS' Thermal Rotary Radiators need to tilt?

This answer shows the first image below of a vintage view of the ISS. Only one of each triplet of thermal radiators is extended from each TRRJ. The ISS' solar panels articulate to modulate the ...
84 views

### What was the most recent launch of a nuclear reactor, and what are the current barriers to launching the next one?

This question about Kilopower nuclear reactors got me thinking. Answer(s) to How many nuclear fission reactors have been launched into space? How many are still there? suggest that most nuclear ...
191 views

### What happened to Kilopower generators?

Why are we still using solar power for spacecraft? Would it be possible to replace the giant solar arrays and batteries on spacecraft with Kilopower generators?
2k views

### Travel Speed in Space

I have read several questions and answers here concerning achieving speeds beyond the typical deep-space exploration missions. While speed increases near the Sun for example, that can't be applied to ...
121 views

### What is crossrange and downrange for an entry vehicle?

I have been searching the terms online but still can't get a more intuitive understanding. If you could refer me to some website, book or if you could offer me an explanation I would really appreciate ...
29 views

### Examples of both hardware and software GNSS recievers

I am writing an essay titled: Critically evaluate the positional fixing capabilities of current smartphone technologies for real world GIS data collection I am wanting examples of both hardware and ...
49 views

### Heat balance of the ISS: breakdown?

Is there available breakdown of the heat balance of the International Space Station? In particular: How much heat is produced? by direct warming by sun by warming of solar panels (heat for the ...
2k views

### What are these stacked panels on the ISS in this image?

I found this image of the ISS in a folder on my computer. I don't know the exact source but a reverse image search shows it in many different websites. Unfortunately I can't pin down a date. What are ...
35 views

### Can the term “space weather” refer to the environment in deep space, or is it only in reference to Earth's (or another planet's) upper atmosphere?

@OscarLanzi's interesting answer and my comment there led me to read Wikipedia's article Space weather. The article exclusively seems to only talk about effects in Earth's upper atmosphere; the only ...
63 views

### Why did Deep Space 1 use solar concentrators?

@Hobbes' answer mentions that Deep Space 1 used special refractive solar concentrators attached to photovoltaic cells. According to SCARLET: The innovative array uses 720 lenses to focus sunlight ...
34 views

### White hole and antimatter [closed]

I have read that a black hole is connected to another parallel universe where everything is contrast. So my question is, are white holes proven? And if they are, then are the planets in the parallel ...
135 views

### Ratio of low-thrust slow spiral to Hohmann transfer $\Delta V$?

Going from one circular orbit to another, there are tables out there and equations that give the total $\Delta V$ needed for a two or three impulse maneuver scenario. For a very low thrust propulsion ...
95 views

### concentrating starlight with mirrors for photovoltaics in deep space

would it be feasible to use mirrors to concentrate starlight in order to produce efficient solar panels in interstellar space? could we produce enough electricity to provide ongoing propulsion?
29 views

### Reaction Drive Launch Catapult

I want to suggest a variation on the launch catapult. The rocket assembly is accelerated vertically through momentum transfer, by a reaction driver on the ground. In concept the driver would be a ...
49 views

### Scoutleader looking for understanding of fuel burn for getting away from earth gravity Vs. fuel expended when traveling from A-B in space

I am a layman scoutleader and like to discuss the amount of fuel needed to get from earths gravity to the thrust needed in space to get from A-B. Is there a spreadsheet that would give course ...
99 views

### How to calculate the kilowatt hours (kW-h) needed for a solar-electric engine to produce a given delta-v?

A spacecraft is in LEO and I would like to reach a certain point in space; let's say Mars. If I look at the diagram in this answer I see that the delta-v from low Earth orbit to low Mars orbit is ...
36 views

### Trajectory impact in case of STS hold down studs failure

The comment on this question made me think, suppose all holding studs mounted on SRB’s do get failed, how much impact would it really result in trajectory, considering same fuel burn time of SRB’s. ...
107 views
+100

### What are these mysterious white dots near MU69 Ultima Thule? Real objects near the asteroid, noise, cosmic rays, or something else?

NOTE: I think either possibility suggested below is possible, I'm not looking for arguments why one of them would be your favorite like this answer. Instead, I'm looking for a fairly conclusive answer;...
76 views

### Highest velocity impact between a spacecraft and a solar system body? What about for a dedicated impactor (spacecraft component)?

In this answer I mention the proposed impact of DART: Double Asteroid Redirection Test (DART) Mission Double Asteroid Redirection Test The Double Asteroid Redirection Test (DART) Element of the ...
18 views

### How do you read an Engine Throttling specification of 3-5:1 in percent thrust load?

I was looking at the CECE engine by Aerojet, however I am not sure how to determine the trust range of percent thrust range of the engine. How I can translate the throttling spec into a percent load ...
71 views

### What systems were used onboard Buran to determine its position during reentry and landing?

Since Buran has managed to return without crew on board, I assume computers had to know its position relatively accurately as it approached the runway for landing. How was this achieved?
128 views

### Is half of a SpaceX fairing a viable lifting body?

If it was powered, would a shape such as a half-fairing produce any lift, or could it be modified to both work as fairing, and lifting body?
66 views

### Is there a list of space exploration mission ordered by “size”?

While playing KSP I came to realize how how counter-intuitive distances in space exploration are. Just because a planet is closer doesn't mean it's easier to get to. For example, I used to think ...
121 views

### Is it justified that ESA is pushing to launch Rosalind Franklin even after Schiaparelli landing failed? [closed]

As far as I am aware, ESA has not achieved a successful martian landing yet. Why is it still a good idea to try with full-scale rover, weighting more than Opportunity and Spirit (though less than ...
672 views

### Crashed LMs visible on LRO images?

I'm rewatching the old HBO "From the Earth to the Moon" series and then reading up about specific missions in detail afterwards. One thing I hadn't realised was that the LM for each mission typically ...
94 views

### What launch vehicle will be used for Exomars rover Rosalind Franklin?

I know that for TGO/Schiaparelli, Proton was used, but I don't know what will be for Rosalind Franklin.
73 views

### Is there an upper stage main engine that is human ratable and may out perform the Common Extensible Cyrogenic Engine performance by Aerojet?

I am fasinated by Aerojet. The CECE, has a total qualified burn time of 10,000 seconds and with a total of 50 restarts. The LOX/LH2 engines have a great performance with a specific impulse of > 445. ...
91 views

### Saturn V and STS holding to launch pad mechanism

In the question in quora, the first answer mentions that in space shuttle they changed the holding mechanism to explosive bolts from clamps in Saturn V. Video Link Copied from the answer, which ...
80 views

### Has foam loss been observed in Ariane 5 launches?

Ariane 5 is similar to the Space Shuttle in that both vehicles are powered by SRBs and use foam insulation in cryogenic tanks. Foam shedding has been a common occurrence during the history of the ...
94 views

### Is a kilowatt per square centimeter a typical launch engine's thermal energy flux (density)?

I saw the following image while searching for this answer in Sung Hwan Kim's thesis Germanium-Source Tunnel Field Effect Transistors for Ultra-Low Power Digital Logic It plots power density in Watts ...
69 views

### Celestrak GLONASS TLE's showing satellite numbers not listed in the GLONASS constellation, others missing

For a project, I'm retrieving TLE information live from http://celestrak.com/ and using them to simulate satellite orbits. The TLE's for the GLONASS constellation (http://celestrak.com/NORAD/elements/...
1k views

### Does a change in the rotational speed of something on its own axis (rpm) affect its orbit?

For example: if a satellite in orbit around earth had its prograde rotational speed increased from 60 rpm to 600 rpm, would its orbit be affected? Another example would be if earth’s rotational speed ...
7k views

### How do astronauts keep their devices dry?

In these videos astronauts are drinking and playing with water. We can see water droplets floating away to the surroundings. Do these droplets affect the machines in any way? What do astronauts do to ...
248 views

### Is an elliptical orbit around a black hole, or an orbit consisting of three bodies (including the black hole) possible? [migrated]

If this is possible, would it then lead to an object undergoing varying time dilation (predictable variation with elliptical and random variation with three body)?
201 views

### What is this balloon for in this clean room and what is the proper name for the “stand” that is holding the satellite?

What is this balloon doing in this clean room and what is the proper name for the "stand" (white & blue) that is holding the satellite?
140 views

### Creating your own artificial gravity by running. (Part 1 - the basic idea)

The main motivation for artificial gravity is the astronauts' health Usually artificial gravity is supposed to work by rotating the spacecraft. See diagram A. Wouldn't it be much simpler to simply ...
77 views

### Artificial Gravity - How much is needed per day?

Has any research been conducted or is anything known about how much time must be spent in 1G per 24 hours in order to preserve good health? Assume that this refers to an extended space-journey. The ...
15 views

### Will the Insight seismometer use the deployment of the Heat Flow and Physical Properties Probe as a known impact source for sounding purposes? [duplicate]

As the Heat Flow and Physical Properties Probe (HP3) hammers itself into the Martian soil, it will generate impacts of known intensity. I have not been able to find anything on https://mars.nasa.gov/...
21 views

### Where Can I start learning / taking some online courses on remote sensing, processing the remote sensing data and general space technology basics? [closed]

Would like to learn about processing the remote sensing data. As of now I have started with sentinel data. But would like to know more to understand all the terms involved in it completely. Looking ...
3k views

### How is sunlight simulated in spacecraft testing, given its brightness?

How could a light source like the sun be approximated on Earth for testing, given how much brighter it is in space than anything else?
70 views

### Moon Polar Days And Night

Moon's rotation axis from the orbit plane of earth is about 1.54° tilted. Just like earth because of tilt, do polar regions experience 6 months day and 6 months night? If so, aren't these places ...