Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [low-earth-orbit]

Questions regarding Low Earth Orbit or LEO, which refers to orbits at an altitude between approximately 160 kilometers / 99 miles and 2,000 kilometers / 1,200 miles.

4
votes
1answer
111 views

Could a spacecraft produce lift using sublimating material?

Following this question, could a spacecraft approaching upper atmosphere from very low circular Earth orbit, produce lift to soar propulsively, bleeding speed at constant apoapsis, by sublimating ...
2
votes
1answer
63 views

Does launching to interplanetary space from LEO require the least delta-v?

Based on this chart from wikipedia, (I do not know if I am reading it correctly) This all assumes LEO-Eq LEO to C3/0=3.22 LEO to GEO to C3/0=3.9+1.3=5.2 LEO to EML-1 to C3/0=3.77+0.14=3.91 LEO to ...
1
vote
1answer
106 views

How long could a spacecraft be attached to ISS?

I've recently noticed how the "Design life, when docked to Space Station" parameter, varies across some of the modern spacecraft that are capable of docking to ISS these days: H-II Transfer Vehicle - ...
2
votes
1answer
58 views

Where can I find the TLE of ExseedSat 1, India's first ever private LEO satellite?

On 3rd December 2018, a private Indian company Exseed Space launched it's first ever satellite into space called ExseedSat 1. But I couldn't find the TLE for this satellite. I looked it up on n2yo ...
1
vote
1answer
75 views

Atmospheric re-entry speed

What would be the difference in atmospheric re-entry speeds from LEO and GEO, assuming a Hohmman transfer orbit from GEO to re-entry? If I am getting the transfer orbit concept correct?
2
votes
1answer
93 views

Calculating the radial, in-track and cross-track distances

I'm computing the relative distances between satellites. The following picture shows the distances, which are considered as risky. What do Radial, In-track and Cross-track mean and why are they ...
3
votes
2answers
64 views

Cubesat mass density (kg/U) statistics?

The stuff of which COTS cubesats are made (aluminum, silicon, G10/FR-4, battery) has a density in the ballpark of 2 to 3 (g/cm^3) while vacuum is roughly 0. I'd always figured that cubesats built from ...
0
votes
1answer
126 views

Satellites that take advantage of, or require constant availability of sunlight on the spacecraft itself, available in Sun-synchronous orbits?

ditto: "Are there satellites that take advantage of, or require constant availability of sunlight on the spacecraft itself, available in Sun-synchronous orbits?" This question is an offshoot of this ...
6
votes
1answer
118 views

What are the causes of these episodes of faster than average altitude loss by the ISS?

@Cristiano's question No reboosts for the ISS shows the plot below. I don't have the original source. I've added some annotations including four arrows to indicate what looks like short periods (a day ...
3
votes
2answers
98 views

How much fuel to maintain VLEO for communication satelites?

A recent answer about communication satellites in VLEO (≤350 km) estimates a useful orbital life of about month without fuel. I.e. Once the vehicle is out of fuel to maintain orbit, THEN it has ...
5
votes
1answer
148 views

How low is VLEO? (FCC's newest approval for SpaceX)

Engaget's SpaceX gets FCC approval to deploy thousands more internet satellites says SpaceX's plan to build a global, high-speed wireless internet network using satellites has taken another step ...
7
votes
2answers
141 views

How is a satellite constellation launched?

If want 10 satellites chasing each other around the earth (evenly spaced) all one the same plane, these satellites would be evenly distributed around the globe after launch by slightly raise or lower ...
11
votes
3answers
1k views

Why are there no LEO satellites in the earth's equatorial plane?

From my elementary school understanding of Satellite orbits, I know that GEO satellites are placed in equatorial plane, MEO satellites are placed in an smaller degree inclined plane while LEO ...
0
votes
3answers
178 views

Was Roadster (Starman) seen in Earth orbit, before the long burn to deep space?

Discussion in comments below this answer tend to conclude that 1st stages come back to Earth and so (essentially) all those tumbling rocket body objects in Heavens Above are 2nd stages, though I ...
2
votes
0answers
62 views

Spacecraft-fixed coordinate system

I am working with data from a polar-orbiting satellite (inclination 97 degrees) with limited attitude information. I am trying to define a coordinate system which is fixed with respect to the ...
3
votes
0answers
61 views

How much is LEO worth?

I've seen valuations of the space industry at ~$350bn annually. How much of this is coming from LEO vs MEO/GEO?
6
votes
1answer
213 views

Did the Soviet Union put an unmanned satellite in “very low orbit”above the Kármán line which used aerodynamic attitude control?

This interesting, archived page https://www.webcitation.org/618QHms8h?url=http://www.fai.org/astronautics/100km.asp which I found in this answer, says: Later in the same decade (or very early in ...
0
votes
0answers
93 views

What is the speed of ISS relative to ground surface?

Is it 7660 m/s or (7660-460)m/s? If it is the former then the ISS orbits about the Earth at 8120 m/s. I think it should be (7660-460)m/s relative to ground based on this orbital period formula, $$T=...
0
votes
0answers
183 views

How to calculate azimuth and elevation angles from satellite point of view of a ground station?

How to find azimuth and elevation from satellite of a ground station when yaw, pitch, roll, lat, long position of satellite and lat, long position on ground are given? ...
1
vote
0answers
30 views

Parameters and restrictions of a Single-satellite and Single Ground Station system [closed]

I am designing a ground station system to retrieve data from a single satellite sending at a given bandwidth in LEO, and I am confused of which parameters I have to take into account when designing a ...
1
vote
0answers
78 views

Attitude of the upcoming “Orbital Reflector”; will it result in good visibility?

There's a new (passive solar) orbital reflector, called the Orbital Reflector. While Mayak (Маяк) was a crowdfunded project at Moscow State Mechanical Engineering University and the Humanity Star ...
9
votes
2answers
2k views

Are there satellites in LEO that can be seen by naked eyes in the daytime?

Are there any satellites in LEO that we can see with naked eyes in the daytime, or any special situations where they might become visible during the day? If there is, how high, and at what ...
0
votes
1answer
84 views

Does a LEO mission to study the marine debris exist or is at least planned?

Would a mission to LEO to study and record the amount of marine debris be of use or is someone already doing it?
1
vote
0answers
74 views

Lighting an area of the Earth Surface from LEO

What does the math look like to calculate the size of an object in LEO that when angeled off the sun, would illuminate a part of the Earth's surface? For example, if I wanted to 'lightup' a square ...
3
votes
1answer
114 views

Hyperspectral Imaging from Low Earth Orbit

We're going to be putting a CubeSat into orbit next year and want to use a hyperspectral imaging device onboard. My questions relates to the maths needed to calculate the imaging lens needed to ...
5
votes
0answers
136 views

Split cost of bringing 1 kg to LEO

Historically seen, space logistics prices decrease, as shown here, from $20K/kg to expected 1.7K/kg thanks to reusable rockets. But, how does the cost split look like and vary in detail? i.e. "fuel - ...
10
votes
1answer
523 views

Have spacecraft ever dipped below the Karman line and then safely continued spaceflight?

The item in Science Alert's A Harvard Astrophysicist Says Outer Space Is Actually Closer Than We Think (see also Science; Outer space may have just gotten a bit closer) talks about the recent Acta ...
2
votes
1answer
144 views

How rare is it in the 21st century to use five stages to get to LEO, especially for a low-mass payload?

@BobJacobsen's comment about the MX Missile (and protests) in the 1980's got me clicking in Wikipedia, which led me to the Minotaur IV launches, the most recent of which seems to be ORS-5 or "...
3
votes
1answer
102 views

What are these bright streaks in MODIS Earth images? Why are they shaped this way?

The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua (EOS PM-1) satellite generates images of most of the Earth each day, though there are small gaps near the equator where the ...
2
votes
0answers
72 views

thrusters, force torque, distribution matrix , orbit maneuver

I have a few questions about computing torques and forces. I use the same configuration as in the thesis titled An Attitude Control Sysytem Design Based on the Turksat-1b Geostationary Satellite. ...
4
votes
1answer
276 views

How to calculate the orbital distance between 2 satellites given the TLEs

I have 2 LEO satellites with the same orbital plane with same inclination & longitude of the ascending node. I have the TLEs for each satellite. How do I calculate the orbital distance between the ...
5
votes
1answer
413 views

How do I determine the ground-track period of a LEO satellite?

I was analyzing a LEO satellite with polar orbit for work purposes. I am relatively new to the field of Satellite orbits. I know that TLE can give information about the current & future orbits ...
9
votes
2answers
298 views

Can ISS astronauts see the lava from the Kilauea volcano at night?

The google news said "Lava from the Kilauea volcano can be seen from space" but it just links to the YouTube video of the same name. The screen shot of the video below shows a small ESA credit at the ...
4
votes
0answers
75 views

Multiple problems with horizontal launch and cryo storage for Stratolaunch?

The Stratolaunch system claims to be a way to revolutionize launching into LEO. The many problems associate with stress loads for horizontal assembly and the need to carry a rocket to launch altitude ...
8
votes
1answer
1k views

How much fuel is necessary to cause delta-v?

For a project, I need to calculate how much thrust and how much fuel I need for getting into LEO. What I know: Delta-V necessary ($\approx 9.4$ km/s) Dry (empty spacecraft mass) What I don't know: ...
5
votes
1answer
176 views

Can you operate a satellite in the disposal “graveyard” region

The NASA safety standards allocate the region between 2,500km to 18,833km altitude for the disposal of LEO satellites. Most satellites, as far as I understand, will either operate in LEO (so well ...
8
votes
1answer
380 views

Propagation of pressure waves in Low Earth orbit

So in a Wikipedia article about space debris i read that---- At higher altitudes, where air drag is less significant, orbital decay takes longer. Slight atmospheric drag, lunar perturbations, ...
4
votes
1answer
125 views

How to determine the optimal orbit for a LEO satellite

Our goal is to determine the best orbit that will allow a ground station (so this is a fixed point on earth) to communicate a maximum number of times par day with a LEO satellite. So the question is :...
4
votes
2answers
224 views

Hovering Carbonite! Why do these satellite videos of Earth appear to be made from a geostationary location?

The BBC News article UK satellite makes HD colour movies of Earth has led me to a series of YouTube videos as well recorded by the Carbonite-2 spacecraft built by Surrey Satellite Technology to be ...
7
votes
3answers
1k views

To what extent is the orbital Time Period of ISS affected by soyuz thrusters?

Numerically, to what extent is the orbital time period of ISS affected during the time when it boosts back higher to gain the lost altitude, using Soyuz thrusters/engines?
30
votes
2answers
4k views

Which LEO satellite lost over 30 km of altitude in the geomagnetic storm of 13-14 March 1989?

This answer includes the following information: During the great geomagnetic storm of 13-14 March 1989, tracking of thousands of space objects was lost and it took North American Defense Command (...
4
votes
3answers
591 views

Why doesn't the ISS use ion engines to maintain altitude?

So the ISS uses small thrusters on the Soyuz (usually) to perform occasional reboost burns to raise its orbit. This goes through, from what I can tell, around 3,500 kilos of fuel per year. Would it ...
1
vote
1answer
98 views

How does DigitalGlobe plan to re-image a specific area “as frequently as every 20 to 30 minutes”?

The Spaceflight Now article DigitalGlobe books two launches with SpaceX for Earth-imaging fleet goes beyond describing the two launches to talk about DigitalGlobe's future plans. Fitted with ...
15
votes
1answer
3k views

Was SpaceX's launch of Formosat-5 more vertical than normal for any particular reason?

Reading both the abstract and the plain language summary of the recent paper published in the journal Space Weather Gigantic Circular Shock Acoustic Waves in the Ionosphere Triggered by the Launch of ...
1
vote
1answer
62 views

How large would be the seasonal variation of eclipse duration for a spacecraft in LEO?

The question How long will a 500 km altitude satellite spend in Earth - shade per orbit has several answers, and there is some discussion of constraints related to maximum eclipse, due to some issues ...
3
votes
2answers
216 views

How fast is the onset of periodic eclipse for a spacecraft in LEO?

A spacecraft in low inclination LEO will undergo regular eclipsing of the Sun and this is a big issue for power management. How fast is the light-to-dark transition, say 90% to 10% sunlight intensity ...
6
votes
1answer
229 views

What are the legal implications for a child being born in space?

So, in this case, I asked back in the chat about the side-effects of childbirth AND what legal implications that would have for a person born outside of a celestial body; a "spacer", if you will. So,...
2
votes
0answers
80 views

How can I plot a precessing orbital plane of an artificial satellite on a polar plot from a TLE in Python?

How can I plot the orbital plane of an artificial satellite on a polar plot from a TLE in Python? Very new to all of this. As I understand it I need to extract TLE's from Space-track.org. Then use ...
2
votes
1answer
109 views

How can you calculate the minimal cone angle between two satellites to prevent interference?

I have a model of 2 ground stations (G1 and G2) and 2 LEO satellites (S1 and S2). G1 and G2 are located close to each other. S1 transmits data to G1 and S2 transmits to G2 with almost the same ...
2
votes
1answer
122 views

Could a sounding rocket or a space gun payload at apogee be put into orbit with a rocket impulse from there?

Consider a sounding rocket that launches its payload to several hundreds of kilometers of altitude, straight up. Imagine that this payload at apogee then points itself accurately and has a propulsion ...