Questions tagged [artificial-satellite]

Questions about objects in orbit which are human made, such as communications and GPS satellites, orbital observatories and space stations, and other man-made object in permanent or semi-permanent orbits around the Earth, other celestial objects, aside from the Sun, or even other satellites. Not to be confused with non-orbited man-made objects in space, that are usually referred to as "probes", or simply "spacecraft".

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5
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1answer
56 views

ISS attitude yaw pitch roll conventions. Which one to use?

I found three definitions for the attitude angles of the ISS (yaw, pitch and roll), from three different source. They contradict each other. See the following pictures. For my problem, I have to ...
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2answers
76 views

What is the most likely range of orbits for on-orbit servicing satellite?

An on-orbit servicing satellite (OOS) is one what would be use for servicing, refueling, assembly in space. Would there be any specific orbit or standard orbit or at least most-likely range of ...
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1answer
56 views

Two line element set

I was wondering where I could find the TLE of a satellite ( I am looking for CASSIOPE). I went into this link - https://www.n2yo.com/satellite/?s=39265 but it has only got the most recent updated TLE. ...
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1answer
71 views

What exactly is SL-24 DEB (2010-028D)?

After 3 months of work I've been able to spot satellite debris with my 20x80 binoculars for the first time. The object in question is SL-24 DEB (2010-028D). According to the data presented in www.in-...
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1answer
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Could a Falcon Heavy really put six GPS Block III satellites in orbit at the same time?

This answer says: GPS Block III satellites are being launched to replace failed or aging Block II satellites, which doesn't require launching more than one at a time. A Falcon Heavy could fill up ...
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59 views

Satellite spotting

My normal activity in early morning and evening is to count how many satellites I can spot which is between 5-7. At 6 am on 22nd November I counted 51 all in single file some 3 abreast; it was ...
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3answers
767 views

Why is one Starlink satellite not following the adjacent one in this image?

The following image shows trails of SpaceX’s Starlink satellites as seen in the sky above the Cerro Tololo Inter-American Observatory (CTIO) in Chile: Image Source: SpaceX’s Newly Launched Starlink ...
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1answer
40 views

Working principle of earth sensor

In satellite systems to derive attitude sometime earth sensor is used. This basically outputs two axis information which when combined with orbit knowledge and sun vector from the sun sensor provides ...
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3answers
211 views

Why are the poles of the Moon in Google Earth so different from other regions?

I am well aware of the fact that the poles of the Moon are different from the rest of the regions in many ways. But in Google Earth's Moon, the poles are so different from what we would see if we were ...
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3answers
676 views

Why is the Duration of Time spent in the Dayside greater than that of the Night side of the Moon for Chandrayaan-2 Orbiter?

The following information is from ISRO's webpage on "Detection of Argon-40 in the lunar exosphere" (Textual information relevant to my question is in bold face): The Chandra’s Atmospheric ...
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1answer
2k views

Commercial satellite retrieval - possible?

I know that the space shuttle was originally designed with the capability to retrieve satellites from space, but I'm wondering if in the commercial market right now if there are services that allow ...
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70 views

How to satellite-to-site range given site coordinates and satellite ephemeris?

How can I calculate the distance of a position on earth to a satellite (for example a GPS satellite)? The satellites position is exactly known by its ephemeris data. In a related question I've asked ...
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1answer
125 views

How exactly does atomic oxygen cause problems for spacecraft in VLEO?

In very low Earth orbit there are (at least) two problems; aerodynamic drag, and atomic oxygen (O rather than O2). Drag can be compensated with a low thrust from an ion engine. Question: But what ...
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142 views

Do satellites in orbit undergo translational motion or rotational motion, when initially they are not given any additional spin?

Regarding the proposed duplicate: Thought the proposed duplicate has a similar titIe, I have read those answers and this question requires a different answer. We know satellites orbit around Earth, ...
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1answer
82 views

Inclination maneuvers for GEO satellites

I was wondering about the orbital location to perform inclination nulling maneuvers for GEO satellites. I know from basic astrodynamics that the best place to perform inclination correction is at ...
7
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1answer
149 views

How has the brightness of SpaceX's Starlink constellation changed since May?

Shortly after the launch, before full orientation of the solar panels and raising of the orbits, the Starlink satellites were surprisingly bright and easily seen with the naked eye. Back then, I heard ...
6
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1answer
595 views

How to calculate the force required to maintain a 10 km diameter disc in a low 80 km orbit?

What force (in the form of periodic impulses) is required for thrusters (thermochemical, electrical, electromagnetic, ionic. Photonics, Hall) to keep such a disk in orbit (80 km) above a fixed point ...
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0answers
48 views

Predicting non-Iridium flares and Why NOSS satellites flare?

I just saw two point-like sources flaring in the sky in perfect sync. It was spectacular and a big surprise to me. The full event lasted at most 4 seconds. My position is in the Usera district in the ...
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1answer
95 views

What is the purpose of orbital frame of reference for a satellite orbiting the earth?

Orbital frame of reference: a frame of reference with its origin on the orbit and x-axis pointing towards the velocity vector and z-axis towards the center of mass of the earth. the y-axis completes ...
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1answer
68 views

Could any “Well-Tracked Analyst Object” turn out to be a natural object or even something else?

The excellent satellite tracking database www.space-track.org, which is mantained by the United States Space Command, offers to the public accurate and up-to-date orbital elements for thousands of ...
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1answer
78 views

What are those tilting/rotating platforms called that hold spacecraft during assembly, testing, and sometimes transport? [duplicate]

The first image from the BBC's Euclid space telescope to study 'dark Universe' makes progress reminded me of the second two, which are taken from What are these air-vent-like structures on this ...
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38 views

Parallax calculation

Given two points of observation on Earth (obs1=[lat1,lon1], obs2=[lat2,lon2]) and the apparent azimuth and altitude of a target from these two locations ...
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3answers
125 views

How is the brightness of satellites measured?

We would like to perform measurements of the brightness of Starlink satellites. Is there any approved technique available ? I see the name Mike McCants connected with magnitude values of ...
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2answers
4k views

In what state are satellites left in when they are left in a graveyard orbit?

I had this idea for a fictional scenario in which a forgotten satellite, like a communications satellite that was decommissioned because it was replaced by a newer model, was hacked into and then ...
5
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2answers
157 views

Can the electric field of the Earth's be used for satellite maneuvering?

Is it feasible to create a strong dynamic dipole inside a satellite so that it can be rotated on its axes and even possibly pushed in a direction due to the Earth's Normal Electric field. This might ...
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2answers
147 views

How to shoot a raspberry pi mini computer into orbit

I'd like to shoot a raspberry pi into orbit. How difficult is this and is this something that could be achieved by hobby rocket scientists?
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1answer
214 views

Why were Europe's first few satellites so stylish? Why the pronounced alternating white and black stripes?

In The Century of Space Science, edited by J.A. Bleeker, Johannes Geiss, M. Huber, viewed in Google books I ran across the following text and images. Both satellites are quite stylish looking and ...
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2answers
4k views

Is it possible to observe space debris with Binoculars?

Recently I've started to observe satellites with my 20x80 Binoculars. I'm amazed by the fact I can clearly track satellites and rocket bodies at 2000 km altitude (I've reached 8 mag with some objects) ...
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1answer
56 views

Does deploying an artificial planet help us study and collect more detailed data about the solar system and the universe?

If we have a space station that can orbit like a planet, wouldn't it give us an advantage in terms of positioning for astronomical experiments? This may also enhance the network transmission ...
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0answers
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Calculation of collision probability based on TLE

I have to calculate the probability of collision at moment $t$ with space debris. I am using JSPOC algorythm described in https://www.space-track.org/documents/...
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4answers
6k views

Why does the U.S. military maintain their own weather satellites?

Why does the U.S. military maintain their own weather satellites like the DMSP Block 5D2? What's the difference to "normal" weather satellites? Do they use other sensors or orbits? If they have ...
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1answer
70 views

What is the cause of the Terra Satellite color as seen from Earth?

Yesterday I spotted the Terra Satellite (EOS AM-1) with my binoculars. This is the 22nd satellite I've spotted. It all looked like usual but there was something very different: the satellite was ...
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1answer
79 views

Spacecrafts: NED frame to Orbit Frame or Body Frame Transformation

I calculate the geomagnetic field using IGRF model in Matlab. However, the output is in the NED coordinate frame and I want to tranform it into the Body frame. I've searched everywhere and I cannot ...
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2answers
147 views

When calculating the future orbit of an artificial Earth satellite, is the Moon's gravity significant or insignificant?

Imagine a mathematician is plotting the future orbit of a satellite to be launched and put in orbit around the Earth. When they are making their calculation, is the moon so far away and the ...
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0answers
32 views

Orbital period from TLE data [duplicate]

Is there a way to calculate the orbital period from the Two Line Element (TLE) data?
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2answers
82 views

What is the process to verify the orbit of a satellite in a list of artificial earth satellites?

From the answers to What is the name of the 'register' that keeps track of all the satellites? we can see that there are more than three 'registers' of artificial satellites - starting with: The ...
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2answers
125 views

What is the name of the 'register' that keeps track of all the satellites?

I imagine there must be a list of all the satellites ever launched and their coordinates. I can't find it on Google. My question is: What is the name of the 'register' that keeps track of all the ...
4
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1answer
133 views

Can a Space Telescope orbit so it was always in the shadow of the Earth?

Imagine you have a space telescope that had temperature sensitive instruments. (Like the Spitzer Space Telescope). In order to maintain a cool temperature - you want it always to orbit in the shadow ...
37
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1answer
4k views

Are there any satellites in geosynchronous but not geostationary orbits?

I know there are a lot of geostationary satellites out there, but I'm wondering - are there any geosynchronous satellites that are not geostationary (ie - have a notable inclination to their orbit)?
11
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2answers
506 views

What was the average temperature of space near the Spitzer Satellite Telescope?

The Spitzer Space Telescope, formerly the Space Infrared Telescope Facility (SIRTF), is an infrared space telescope launched in 2003, to be retired in January 2020. The temperature of space near ...
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0answers
116 views

Orbiting clock visible with the naked eye

Does anyone remember from the 1980s or possibly early '90s in the UK news a (serious) story about contructing a huge orbiting clock so that people would be able to look up at the sky to read the time ...
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3answers
207 views

Are there any designs of geostationary satellites available online?

Are there any designs of perhaps old geostationary satellites available online? After searching around I was mostly able to find either crude diagrams or designs for little cubesats, but nothing for ...
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0answers
72 views

Why did GRACE mission have launch window?

GRACE mission which was launched on March 17th, 2002 had a 10 minutes launch window. The mission was to launch a couple of earth observation satellites. And interestingly, NASA's GRACE Launch Press ...
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How will the RADARSAT Constellation Mission (RCM) satellites achieve their final orbital spacing?

The informative page shows that the RCM satellites are intended to orbit as follows: Sun-synchronous circular orbit (dawn-dusk mission), nominal altitude = 592.7 km, inclination = 97.74º, period ...
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5answers
3k views

How could a satellite follow earth around the sun while staying outside of earth's orbit?

I'm wondering if its possible for a satellite to follow earth around the sun while staying outside of its orbit. I wondering for the sake of space based solar infrastructure or just something ...
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1answer
96 views

PIR application as a sun sensor

Is there any history or merit to using a PIR (Pyroelectric ("Passive") InfraRed Sensor) as a sun sensor for determining the attitude or position of a Satellite?
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1answer
1k views

How many satellites can stay in a Lagrange point?

Lagrange points as I understand it are points in space between 2 objects where the gravitational pull between them is effectively equal. That makes station keeping at these points relatively easy. ...
5
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1answer
752 views

How precise must a satellite's orbit be?

I was thinking about the question on solid upper-stages and my feeling that a liquid upper-stage would allow a more precise orbit. But... how precise does an orbit actually have to be? I guess I mean ...
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0answers
44 views

Using Differential Equations to model path of satelite around earth

I am new to GMAT and am hoping to use it to model the path of a Low Earth Orbit satellite around Earth. I am thinking of plotting the path on a plane and using polar coordinates to model the path ...
3
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1answer
147 views

Could two satellites in the same orbit, but phased differently, be tethered in a sustainable manner?

Was reading this, and I immediately saw the problem with the angular momenta not lining up. Unfortunately, my mind likes to keep turning scenarios over and asking what would happen if ...