40 votes
Accepted

Does the International Space Station get TV?

More or less. While the ISS is below the satellites use for TV transmissions, it is passing by so fast that the coverage will be highly intermittent, meaning that you would be able to watch a ...
Antzi's user avatar
  • 12.6k
33 votes
Accepted

What would be the first noticeable consequences to the general public of widespread satellite destruction?

What would you notice first? Satellite navigation: immediately (depending on how often you use satnav) TV: immediately (depending on how often you use TV). Even if you don't use satellite TV ...
Hobbes's user avatar
  • 128k
28 votes
Accepted

SpaceX's 4,425 satellite constellation - what's the method to the madness?

Nodal precession doesn't matter for a plane of satellites like this, they will rotate around in unison, so the coverage will remain the same. Okay. So, why the unusual dual inclination constellation? ...
PearsonArtPhoto's user avatar
  • 121k
26 votes
Accepted

What is carrier lock and bit lock?

First you lock on to energy at (or near) the expected frequency. That’s carrier lock. Then you start to look for patterns in how the phase changes. The transmitter is coding groups of bits as phase-...
Bob Jacobsen's user avatar
  • 12.7k
25 votes
Accepted

Why are obsolete geostationary satellites re-orbited above the geostationary belt?

Orbits at the altitude of GEO are stable for very long times (millions of years). There is no significant decay of the orbital height due to some kind of drag, so the risk of these satellites ...
asdfex's user avatar
  • 15k
24 votes

Quantum technology for starship communications and landing on Mars

No, quantum mechanics cannot be used to transmit information faster than light. This is a common misconception based on misunderstanding how quantum mechanics works. Go here to read more about it. ...
Knudsen Number's user avatar
22 votes
Accepted

Would adding satellites between Earth and Mars improve communications latency?

No. Communication latency (the time between sending a bit and receiving it on the other end) between Earth and Mars probes is limited almost entirely by the speed of light, as they are radio waves on ...
Nathan Tuggy's user avatar
  • 4,566
22 votes

Will Curiosity and the Mars 2020 rover be able to communicate with each other via a Mars orbiter?

Yes, they could theoretically communicate with each other over the DSN, however in practice this will not happen (as it has no current uses). The amount of functions that Curiosity can perform ...
Dragongeek's user avatar
  • 18.8k
22 votes
Accepted

Why do Teledesic satellites look so weird? What are these structures and where's the satellite bus?

After a great deal of searching, I found a PDF here, by Mark A Sturza of Teledesic. There's a basic diagram of the satellite on page 8 (Image credit: Teledesic Coporation) There is also the ...
Dave Gremlin's user avatar
  • 2,891
21 votes
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Is it normal for the US Space Force to warn companies about a possible collision (conjunction)?

Space Fence is what our current tracking system is called. This article claims that some companies and countries have an arrangement to receive tracking data, but few details. It appears that this in ...
Harabeck's user avatar
  • 338
20 votes

Why are obsolete geostationary satellites re-orbited above the geostationary belt?

Actually, it makes a lot of sense to raise the orbit of end-of-life geostationary satellites: Coming from Earth you have to cross through a lower orbit to transfer from low earth orbit to a ...
1337joe's user avatar
  • 7,206
20 votes

Why didn't NASA launch communications relay satellites outside the asteroid belt to communicate easily with interstellar satellite?

There is no relay in place because we can communicate with probes at long distances already, and a relay at the orbit of Jupiter or Saturn wouldn't make much difference due to the distance involved. ...
GdD's user avatar
  • 20.3k
19 votes

Quantum technology for starship communications and landing on Mars

There's already two good answers that say a lot of what I wanted to say, and I will refrain from repeating any of their content here. I do think it is useful to add one more item of insight though. ...
user1271772's user avatar
18 votes
Accepted

Are commercial communications satellites in GEO being constantly monitored by telescopes?

It seems that the company ExoAnalytic Solutions regularly observes high- orbiting satellites (MEO, HEO, and GEO), using the data to provide tracking, ensure they are at the right spot, and provide ...
PearsonArtPhoto's user avatar
  • 121k
17 votes
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What (actually) makes Iridium "the world's only truly global mobile satellite communications company"?

As of today (October 2016), Iridium is the only public satcomm provider using a constellation of low earth orbit satellites with high inclination orbits to provide a service with global coverage. You ...
Andreas's user avatar
  • 1,385
17 votes
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How do communication satellites remain positioned above a particular region?

Such satellites are in a geosynchronous orbit (GSO), orbiting at an orbital altitude where orbital period matches Earth's rotation on its axis. Their orbital speed is roughly 3 km/s at mean orbital ...
TildalWave's user avatar
17 votes

Why is there never enough room on satellites to hold all the equipment needed?

Why is there never enough room on satellites to hold all the equipment needed? Welcome to Space Exploration SE! Because of the time involved from planning until completion of goals at the end of the ...
uhoh's user avatar
  • 149k
16 votes
Accepted

Do antennae on the ISS have to constantly move to maintain data links?

The US side of the ISS has a number of antennas to support its rather complicated comm system. Most visible are the two Ku-band High Gain Antennas which are 6 foot diameter azimuth/elevation gimbaled ...
Organic Marble's user avatar
16 votes
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Difference between Tundra and Molniya orbits?

They are definitely not identical. Tundra is geosynchronous; period = 1 day. The eccentricity allows it to spend most of the time over a region of Earth off the equator, something not possible for ...
SF.'s user avatar
  • 55k
16 votes

What would be the first noticeable consequences to the general public of widespread satellite destruction?

The experiment has been done, with a single, geosynchronous, satellite, Galaxy IV, in 1998. The immediate effect I noticed in the San Francisco Bay Area was loss of the live NPR feed. I did not check ...
Bill IV's user avatar
  • 281
16 votes
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Main differences between 5G and Starlink?

Starlink and 5G don't have that much to do with each other--they compete for different customers. Starlink systems currently require a large receiver the size of a pizza box to uplink to satellites. ...
Dragongeek's user avatar
  • 18.8k
16 votes

Why is there never enough room on satellites to hold all the equipment needed?

Perhaps there is an assumption that new photos of Earth taken from space would be inspiring, enlightening, and meaningful in some way. That was certainly true of the first photos that were taken, but ...
Steve Pemberton's user avatar
15 votes

What is the most popular programming language in space?

I wrote code that flew on 3 spacecraft that went to Mars, one to the Moon, one to a comet and back, and a few Earth-orbiting satellites, the last of which was about 10 yrs ago. All of them used C. It'...
RickNZ's user avatar
  • 546
15 votes

Does the International Space Station get TV?

@Antzi's answer is right, but I'll add some context as a supplement. While Doppler (mentioned there) might or might not be an issue for an off-the-shelf commercial satellite TV box (I don't know) it ...
uhoh's user avatar
  • 149k
14 votes
Accepted

Do satellite uplink/downlink signals spread or leak into space?

They have to spread their signal. Also, it requires a really big dish to not spread your signal at all. Imagine that there was no spreading at all. The dish would have to be pointed exactly at the ...
PearsonArtPhoto's user avatar
  • 121k
14 votes

Does SpaceX expect 1 collision involving one of their Starlink satellites every 2 years?

I think you've made a bit of a logical/statistical misstep. Primarily, the "1 in 100,000" figure is a bit misleading because it's not a statistic. It's an operational risk level threshold ...
Dragongeek's user avatar
  • 18.8k
14 votes

Why is there never enough room on satellites to hold all the equipment needed?

You seem to have overlooked DSCOVR, which pretty much just stares at our planet. https://epic.gsfc.nasa.gov/
Organic Marble's user avatar
13 votes

Is it normal for the US Space Force to warn companies about a possible collision (conjunction)?

It's routine, and done as a service for the space community at large. Companies doing official business with the U.S. Government can get access to a variety of additional services, but the basic ...
Ryan C's user avatar
  • 7,942
13 votes

Why is there never enough room on satellites to hold all the equipment needed?

We have a large number of sources taking photos of our planet. This includes: low-altitude Earth observation satellites (Landsat, SPOT, Maxar). These take high-resolution photos of a small area at a ...
Hobbes's user avatar
  • 128k
12 votes
Accepted

What will be "unique" about upcoming SES-9 GTO transfer profile by SpaceX?

SpaceX has stated a goal that every launch going forward will attempt to land. The expectation initially is not 100% success, but an attempt at the very least. Large GTO payloads do not leave enough ...
geoffc's user avatar
  • 79.6k

Only top scored, non community-wiki answers of a minimum length are eligible