Questions tagged [satellite]

Questions regarding an object orbiting around another object due to the force of gravity.

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Fixing satellite eclipse equations from textbooks that are seemingly failing

I have tried implementing equations from two different textbooks in Python to find if a satellite is in eclipse, but both fail a significant percentage of the time when tested against data from ...
Michael Bonnet's user avatar
3 votes
1 answer
184 views

Help me identify an object

Can someone please help me identify the object moving from 'left' to 'right' in the 'upper' part of this video? (please forgive me for the artifact in the center of the video, dealing with FITS files ...
Claudiu's user avatar
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1 vote
0 answers
31 views

What effects you have to have in mind during LEO satellites observations?

I am attempting to calibrate my setup for conducting survey-like satellite observations similar. The idea is that I have a wide-field camera that takes images at 5FPS. The camera is equipped with a ...
jlipinski's user avatar
  • 277
7 votes
2 answers
770 views

How can non-earth-orbiting satellite coordinates be obtained by amateurs?

Just a few hours ago the moon-bound spacecraft Chandrayaan-3 was launched. While it will orbit Earth for a few days, it is accelerating/changing its orbit often to prepare for the transfer to a lunar ...
2080's user avatar
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4 votes
3 answers
332 views

Why don't we use the Voyager/Pioneer etc space probes to measure stellar parallax?

With Earth based telescopes you get a max distance of 2 au between measurements. While we have multiple space probes well over 100 AU away from us, that's a 2 OoM difference.
blademan9999's user avatar
19 votes
3 answers
6k views

Is it possible to have satellites (natural or not) orbit the same celestial object in different directions ? (clockwise, counterclockwise)

Is it possible to have satellites (natural or not) orbit the same celestial object in different directions, or is the orbital direction dependent on the celestial object's spin? Also, is the direction ...
Demis's user avatar
  • 883
2 votes
0 answers
186 views

From TEME to RA DEC

I am using the SGP4 python package to get the coordinates of satellites at a given epoch. The algorithm computes the positions (X, Y, Z) in the True Equator Mean Equinox coordinate frame (TEME). From ...
laetitia's user avatar
4 votes
1 answer
73 views

Contamination problem data

I do not have a source for this statement. A teacher just said it. Could you tell me what 'a contamination problem' mean? He explained that 'stellar images from a space-based photometry data have ...
Elena Greg's user avatar
4 votes
2 answers
57 views

Could a rogue comet perturb a frequently occurring meteor shower to the extent that debris falls on Earth...and dislodges satellites?

This is for a work of fiction that I started five years ago. Clever people from Astronomy Stacks answered several questions for me back then. Now that I am in the final edit of this manuscript, I find ...
Evelyn 's user avatar
2 votes
0 answers
67 views

Satellites or UFOs? [closed]

Last night in Greenville MI at around 9:15pm-9:25pm (I don't know the exact time) I saw what appeared to be a satellite appear and disappear and then a few seconds later another possible satellite ...
Michael's user avatar
  • 31
1 vote
0 answers
474 views

What was this "light" that looked like a star moving repeating from point A to B for about 5 mins [duplicate]

I was looking in the sky one night about 9:45. There was what looked to be a shooting star but much slower and brighter more like a satellite. It was moving (from standing on earth) it looked like a ...
DJ7420's user avatar
  • 27
8 votes
1 answer
6k views

I saw a short-lived brightening and fading of a light in the sky. Was that a star imploding, exploding or going super-nova?

I was looking over the north-eastern skyline from a west coast location and notice something very bright for well over about 10 or 15 seconds, and then it faded completely. I didn't notice it before ...
Terry Dunn's user avatar
14 votes
2 answers
8k views

What could be an explanation for a satellite-like moving light in the night sky that dims over time

Last night I saw a bright light moving across the sky. It was probably as bright (or even brighter) than some of the brightest visible stars like Vega and moving quite slowly (so no shooting star) at ...
299792458's user avatar
  • 343
-1 votes
1 answer
158 views

I believe I saw a UFO, what else could it be? [closed]

When looking at the night sky some time ago I noticed a white dot. The amount of light coming from or being bounced on that object made it the same size of a average star. But differently from a star, ...
Noah's user avatar
  • 11
1 vote
0 answers
86 views

Satellite emitting x-rays? [closed]

On the local TV news, it was alleged that x-rays from some satellite could interfere with something on earth. I didn't hear it but my wife thought they were talking about WiFi or internet or ...
WGroleau's user avatar
  • 141
1 vote
0 answers
306 views

Converting a Satellite's position in Lat/Lon/Alt/Time to RA/Dec

I'm trying to convert a satellite's position given in latitude/longitude decimal degrees, altitude in meters, and time in milliseconds since epoch to right ascension and the declination. I have found ...
MrForum's user avatar
  • 11
10 votes
4 answers
3k views

Why do satellites appear as streaks in telescope images?

Can you explain me in simple words why the satellite in this telescope image appears as a streak? The exposure time is 1 second.
Gargolla9's user avatar
  • 111
3 votes
2 answers
463 views

Satellite?? Star?? I am puzzled over what I just saw

I was just outside between 6:10 - 6:12 a.m. this morning (Sep.11/2021) and between this time saw the strangest anomaly in the sky. It was still completely dark outside, the stars were extremely clear ...
Sam's user avatar
  • 31
1 vote
0 answers
36 views

Dotted line of moving objects observed on May 5th and May 12th [duplicate]

I saw a dotted line shooting star-like object May 5th and May 12th. It was longer than any meteor/shooting star tail or trail I've ever seen before. I mean longer in every way, the distance it ...
Kelly Ries's user avatar
3 votes
1 answer
165 views

Orbital decay via gravitational emission in a hypothetical, two-body universe

Assume we have a universe with nothing in it except for two objects. One of them is a stationary object that is perfectly spherical with the mass of the Moon (without any atmosphere, of course; also, ...
slowerthanstopped's user avatar
2 votes
0 answers
32 views

Different approaches to quantify light pollution on a given location on Earth?

The question Light Pollution: what is the difference between artificial brightness and brightness and SQM made me wonder which different ways exist to directly and indirectly quantify light pollution ...
B--rian's user avatar
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1 vote
0 answers
90 views

Calculate Global (ECEF) coordinates of Observer

I have the local coordinates of satellite and global coordinates of satellites. I want to calculate the observer position in global (ECEF) system. How can I do this? I also explain this question with ...
Sun's user avatar
  • 11
3 votes
1 answer
351 views

Throwing a baseball from orbit to the earth

I just read a thought piece about what a war in space may look like, and it changed my thoughts on what orbit actually is. From what I read about orbits, it sounds like going faster in the velocity ...
kmort's user avatar
  • 133
2 votes
2 answers
124 views

I saw 3 consecutive object disappearing in the sky at same nearby location

I was roaming on my terrace and I saw star-like moving object that gradually became small, red colour and disappear. Within a few minutes I saw another similar-looking object a little distance away ...
Dixita's user avatar
  • 29
1 vote
1 answer
112 views

What object did I see in the sky? [duplicate]

Tonight, while looking at the night sky, I saw a moving object which I cannot assign to any cosmic or man-made object known to me. The object looked like a star, and hadn't it been moving, it would ...
srgb's user avatar
  • 113
1 vote
1 answer
147 views

What satellite is this?

While out viewing the Perseid shower last night (8/11/20), we saw an interesting object that I'm trying to identify. We're in the vicinity of Portland, Oregon. It appeared to be traveling west->...
Chris Weiss's user avatar
0 votes
1 answer
161 views

How to calculate shape of orbit when projected onto the plane of the ecliptic

I'm trying to generate an 'overhead' view of the orbits of the moons of Neptune, similar to Figure 4 in this paper, using values given here. I initially tried using both the Argument of Periapsis, and ...
codebox's user avatar
  • 103
3 votes
1 answer
98 views

Brightness, altitude & azimuth for satellites?

I'm using the heavens-above website to identify a satellite I've seen several nights this week. The question is related to how I can search the satellites table with the information I can provide. ...
rbhat's user avatar
  • 401
0 votes
1 answer
71 views

Do Satelites travel in train like formation? [duplicate]

This morning approx 5.30am i seen roughly 12 travelling in perfect formation approx 15cm apart , im 200km south of sydney Australia travelling from a north west direction
Ray Davies's user avatar
1 vote
0 answers
40 views

Stars moving in a straight line in Minnesota [duplicate]

I was outside at around 7:50 to 8:09 ish. At I looked up in the sky to see around 20-50 stars or something moving in a straight line at the same speed. I have never seen anything like this ever. And ...
Isaac's user avatar
  • 11
1 vote
0 answers
36 views

Fast moving lights moving west to east [duplicate]

at approximately 5:45 a.m. Est,I was 20 "stars" moving w to e faster than an airliner. They were about 60 degrees off the southern horizon and took several seconds to cross the sky here in central-...
Jake Lanslow's user avatar
1 vote
1 answer
323 views

Satellites traveling in single file across the sky [duplicate]

I just watched 46 (best count) satellites traveling in single file, about 3 second intervals between them. Is that possible? I don't want to believe they were UFO's. Time was ...
doug wilson's user avatar
21 votes
2 answers
1k views

How will Starlink affect observational astronomy?

I have recently found that people around the world have been posting observations of a line of moving objects in the sky which is very likely to be a part of Starlink satellite constellation, such ...
Leo Liu's user avatar
  • 381
1 vote
1 answer
99 views

Proper Terminology For Satellite Going Into Planets Shadow

What is the proper terminology for when a satellite or spaceship passes into a planet's shadow or night side? Is it crossing the terminator? Passing into eclipse? If there is a different name for ...
Trevortni's user avatar
  • 111
3 votes
2 answers
396 views

How many satellites does the Milky Way have?

The small and large Magellanic clouds are galaxies that are orbiting our own galaxy. How many such "galactic satellites" do we know of?
usernumber's user avatar
  • 17.5k
2 votes
1 answer
163 views

Force exerted by space debris on satellites [closed]

Hypothetically, if space debris were to collide with the currently orbiting satellites, how much force would they exert, and how much damage would they make? Will the satellites be able to withstand ...
user avatar
1 vote
2 answers
246 views

Angle formed between a satellite, a ground station, and then another Satellite

I am trying to check my work on calculating the angle between two sats and a ground station observing those two sats. I have the az and elevation angles to each sat from the ground station. What would ...
Shaps's user avatar
  • 11
2 votes
2 answers
2k views

How to calculate phase angle of a satellite?

I'm making a program for predicting satellite passes. I'm trying to find out if the satellite is illuminated by the Sun and not in Earth's shadow. I need to know its phase angle: the angle between the ...
sunl1t's user avatar
  • 21
16 votes
1 answer
92k views

Line of lights moving in a straight line, with a few following

My husband and I have just seen a line of about 15 lights moving in a straight line, quite high above the cloud level with a gap, and then 5 lights, a gap, another few, a gap, 1 light, a gap, and a ...
Sue Melvin's user avatar
2 votes
1 answer
275 views

How come the Sun does not make the Moon crash on the Earth?

As the Moon loops around the Earth, on one side of the Earth it moves toward the Sun (let's call it downward side) and on the other side it moves away from the Sun (let's call it the upward side). ...
armand's user avatar
  • 393
9 votes
1 answer
2k views

Which Saturn satellite passes closest to Saturn's rings and at what distance?

I was using Stellarium to watch Saturn from its moon Pan and I saw the rings were very close to this moon. Now Saturn's rings extend for a large distance so several moons see them from close. I was ...
Pablo's user avatar
  • 1,103
2 votes
2 answers
123 views

Is there a reason why the IAU differenciates objects in the SS orbiting the sun into a particular classification but it doesnt for satellites?

The IAU has different classifications for objects in the solar system orbiting the sun, they can be according to their shape and if they clear their neighborhood of other material around its orbits , ...
Pablo's user avatar
  • 1,103
2 votes
1 answer
110 views

Do planetary magnetic fields slow the movement of conductive extraplanetary moving objects via induction?

A fixed magnetic field will induce an electrical current in a conductive object moving through the field. The strength of the eddy currents will depend on the shape and composition of the conductor ...
Willk's user avatar
  • 323
1 vote
1 answer
589 views

Computing the local orbital frame vector directions in a geocentric reference frame

In the context of the study of a cubesat (little satellite), I am asked to define the local orbital frame and compute the local orbital frame vector directions as a function of time : Here the ...
user avatar
1 vote
1 answer
1k views

How to get ephemeris data for location?

How can I obtain ephemeris data which fits to a specific location? Differently phrased: I need ephemeris data of satellites which orbited a specific location. Is there a document where I can look up ...
Chris's user avatar
  • 113
9 votes
2 answers
3k views

Calculating the apparent magnitude of a satellite

I'm writing a program that involves calculating the apparent magnitude of satellites from a ground location. I currently have the intrinsic magnitude of the satellites and the solar phase angle in ...
Nick Brown's user avatar
1 vote
2 answers
981 views

How to find the radius of a satellite not knowing the mass

If I know the semi-major axis, the density of the planet, and orbital period.. how can I find the radius of the satellite? I can't think of any formula to use.
loneWolf's user avatar
7 votes
2 answers
735 views

Computing orbit positions of Jovian Satellites / Moons using JPL data

I've been trying to build a model of the solar system in a game. Thus far I've succeeded in placing each of the planets in position using Keplerian elements and formulae from https://ssd.jpl.nasa.gov/...
PKCLsoft's user avatar
  • 211
1 vote
2 answers
6k views

Calculate eclipse days and duration of satellite

If a satellite is revolving in a GEO orbit, then what will be the eclipse duration for it? How to calculate when the satellite will enter the dark side of the Earth? Any formula or online tool would ...
iLLkeeN Nemo's user avatar
3 votes
1 answer
3k views

Help converting ECI to RA DEC

Using the library OrbitTools I can input a TLE and get back ECI coordinates. I want to find the RA DEC though, so I use ...
Gstein's user avatar
  • 31