Questions tagged [data-transmission]
Questions regarding transfer of data from spacecraft and probes
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Does the International Space Station get TV?
For obvious reasons the ISS cannot get cable TV. Can the ISS get the new digital air TV or satellite TV using an issued dish and receiver like a house? How would that be done compared to how it is ...
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MarCo, Polo? Any further news, or images, or transmissions from the MarCo deep space cubesats?
Edit: Two more months have gone by since I posted this question. Can there still be no news? Nothing for the two MarCo cubesats to take photos of; not even each other?
While InSight is still "...
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Why is New Horizons' data transmission speed so slow compared to Voyager?
New Horizons was said to be able to communicate at ~1kbit/s at Pluto and 38kbit/s at Jupiter.
Communication with the spacecraft is via X band. The craft had a communication rate of 38 kbit/s at ...
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How does Curiosity know how to point and move it's high gain antenna in real time?
The Curiosity rover has a compact X-band high-gain antenna (HGA) that allows for low data rate communication directly with Earth, but is used though for higher data rates it usually uses UHF to ...
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Were there any policies or technical reasons for powering down all Apollo ALSEPs in 1977?
I first tried to include this in the question Why were the “perfectly functioning” seismometers placed by Apollo 12, 14, 15 and 16 astronauts all shut off in 1977? but after three comments from three ...
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Has TDRS-13 officially graduated from "TDRS school" (entered into service)?
According to Wikipedia:
TDRS-M, to be renamed TDRS-13 upon entry into service, is an American communications satellite operated by NASA as part of the Tracking and Data Relay Satellite System. The ...
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Does the TDRS user segment ever provide network functionality beyond being a "customer"?
Celestrak's NORAD Two-Line Element Sets Current Data TLE page has many pre-defined categories for quick access for groups of spacecraft that share similar characteristics.
I clicked on the ...
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Does variable distance to Mars affect data transmission rates?
There distance between Earth and Mars varies between 50 - 400 million kilometers because of their orbits. Does this affect data transmission noticeably? I'd naively expect you could transmit 8x faster ...
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Have deep-space spacecraft always used some form of spread-spectrum for data downlink?
tl;dr:
Question: Have deep-space spacecraft always use some form of spread-spectrum for data downlink?
note: I'm looking for some insight into why, and any possible exceptions, not just a "yes" or "...
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Is it possible to extend high speed data transmission with lasers to the distance Earth to Mars?
Data transmission using an optical laser between ground station and a GEO satellite may offer very high data rates, up to 1.8 GBit/s for instance.
But what about a transmission from Earth to Mars ...
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How to calculate data rate of Voyager 1?
I've read the following passage in the answer to the Quora question How can Voyager send a signal strong enough for us to receive, in spite of its enormous distance from us? And how can it have the ...
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What exactly is the interaction that blocked Juno's data downlink near solar conjunction?
According to Space.com's article Juno Phones Home: Jupiter Probe Reconnects with Earth After 8th Flyby, Juno's recent close flyby of Jupiter and data collection happened while Jupiter was too close to ...
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What approximate bitrate is required for interplanetary spacecraft GNC?
What is a rough estimate for the bitrate needed for GNC (guidance, navigation, and control) of an interplanetary spacecraft from Earth? I know it varies a great deal from case to case, but I want an ...
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How do those little dish antennas sticking out of the HST track their target independent of telescope pointing?
Almost all the photos I see of the HST show the two small dish antennas at the ends of the two long, opposing booms with the "top" one pointed straight ahead at 12-o'clock, and the "bottom" one at 3-o'...
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Can we talk to Pioneer 6?
My question is relatively simple in the essence that it takes few words to ask, but scientifically may be a nightmare. In 2000, the Goldstone Deep Space Communications Complex sent a message to ...
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Earth-Mars Radio Blackout: Is it possible to define an extended solar radius to solve this as a geometric problem?
Solar atmosphere causes difficulties in communication during opposition (when Mars is almost behind the sun w.r.t. Earth).
The question is: is it possible to define an extended radius for the sun, ...
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Were the previous Mars landers configured to transmit beacons or data during descent?
The ExoMars Entry, Descent and Landing Demonstrator Module (EDM) Schiaparelli was configured to broadcast a UHF beacon throughout the entry, descent and landing phases using multiple transmitters and ...
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Was the time of Schiaparelli's landing chosen specifically so the Giant Meter Wave Radiotelescope could listen?
The ESA blog post Listening to an Alien Landing describes the plan to monitor a UHF beacon transmitted by Schiaparelli during it's upcoming descent and landing on Mars (2016-10-19 about 14:45 UT). The ...
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Why was Kepler's orbit chosen to continue to drift away from Earth?
The Kepler telescope was launched from Earth on March 7 2009 and placed in an independent orbit around the Sun, with a semimajor axis of 1.0132 AU, period of 372.53 days, and an eccentricity of 0.036 ...
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Why does there appear to be a 180-degree stereo microphone array outside the ISS?
I was watching a feed on the latest footage of Hurricane Matthew as seen from the ISS just now, relayed from NASA TV. Suddenly, I spotted something poking out of the ISS hull in the footage that ...
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Current maximum bandwidth between Mars and Earth?
What is the current maximum bandwidth between Mars and Earth (at their closest), accounting for any satellite/prober/orbiter that is either at Mars or already launched and en route?
So far I've found ...
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How do Mars rovers synchronize with NASA scientists?
If sending data on earth from mars takes e.g 10 min then how do NASA scientists manage to synchronize stuff with Mars rovers ?
Suppose if something goes wrong and it is required to control or guide a ...
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Why are there times when the ISS can transmit audio, but not video?
I am watching the live stream of today(9/1/16)'s spacewalk. The ISS entered a position in space where the video feed was lost, but they are still able to broadcast the audio conversations between the ...
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Do you need a "wire" on a Europa submarine to phone home?
In regards to Europa, what are the limitations regarding current data transmission technology.
Say we were to have an orbiter circling Jupiter, a lander on the surface of Europa and a "swimmer" [...
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What is the advantage of QPSK over FSK or ASK for satellite data transmission?
I am wondering what are the big advantages and disadvantages using QPSK, FSK,and ASK in satellite communication. In our project, which is in phase 3, are we supposed to work with QPSK modulation for ...
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Calculate communications window for LEO
I am designing a communication system for a small satellite. One of the major constraints is the duration of communication between the satellite and the ground station. I did link budget calculations ...
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Will Red Dragon experience a "Communications Blackout" during SRP?
In the recently proposed entry of Red Dragon into the Mars atmosphere, the supersonic retro-propulsion (or SRP, roughly: slowing down using thrusters while still moving against the atmosphere at ...
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Why has the Earth's motion carried it out of view of Pioneer 11's antenna?
According to The Pioneer Missions, my emphasis,
The Pioneer 11 Mission ended on 30 September 1995, when the last transmission from the spacecraft was received. There have been no communications ...
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Are there any publicly available real-time data stream containing measurements outside Earth?
Analyzing data coming from outside Earth (such as the temperature around Curiosity on Mars, or the radiation level on geosynchronous orbit around Earth, etc.) might be an interesting task and/or hobby ...
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LV Telemetry links on the launch pad
Are electronic telemetry and control links (of TT&C - telemetry, tracking and control) to the launch vehicle incorporated into the launch pad umbilical lines and handed off at launch, or is it all ...
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How do rockets stream live video during launches?
Several times when I followed a space launch being broadcasted in the internet, they also included live video from the launch vehicle itself. Such as this ESA ATV launch. Now I don't know if this ...
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How far can SETI's ear listen?
With the current infrastructure available to SETI, how distant would it be feasible to pick up routine radio communications and noise from a planet emitting radio with identical power and signal ...
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Satellites in orbit which transmit data available to public?
There are websites that present home projects where people have successfully received weather satellite imagery from NOAA satellites (such as this one).
I would like to know if there are other ...
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Why have there been no new New Horizons images in the last few weeks?
As I write this, the latest image in the NASA's New Horizon's image gallery is this spectacular photo showing Pluto's atmosphere:
The full web page for the image is here.
That image was posted ...
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Efficiency of communications between spacecraft and control center
In space vehicle control and fault recovery, how it works is that a big brother copy is on the ground and being fed with most recent data from spacecraft, the little brother. This ground one is an ...
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Where are the pictures during the time the pictures are sent from space to home?
Obviously the pics aren't floating around, but how can I explain this to a 10 year old?
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Do astronauts get Netflix on ISS?
I've been wondering about the internet connection on the ISS, and how it's used. We were talking in chat about astronauts personal belongings and free time, and it made me wonder about how they use ...
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Why are space probes / satellites data rates so low? [duplicate]
The New Horizon's data transfer rate is only about 2kbps right now. At its peak the rate was 38kbps. Why is this transfer rate so slow? Is this due to using radio waves, limitations in the data relay, ...
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What type of data did New Horizons send to Earth in order to diagnose the switch to Safe Mode issue?
Recently, the New Horizons spacecraft on its way to Pluto suffered a "hard-to-detect timing flaw in the spacecraft command sequence." Does that mean that it was a multi-threading error or something ...
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Why does data transfer rate decrease with distance
I read that the New Horizon's probe will send data to back to Earth at 3000 bits per second by the time it reaches Pluto.
I don't understand why a spacecraft has to have a lower data tranfer rate ...
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Technological challenges in substituting EO Satellites X-band downlinks with laser downlinks?
The majority of Earth Observation satellites, whether for meteorology or land analysis, downlink their data in the X-Band to either government-run or privately-owned ground stations. In Europe, the ...
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Sneakernet: Would data return together with sample return be useful?
Mars 2020 will drill and store several surface samples until a return-to-Earth vehicle arrives. The rover will then use its arm to move its sample box to onboard the return vehicle.
Could the rover ...
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How far do the omnidirectional Earth transmissions (TV, Radio, etc) travel before they become indistinguishable from background radiation? [closed]
When radio signals leave earth, they propagate out in a wave form. But how far they can “spread out” over distance until they become indistinguishable from background noise?
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What evidence would be needed to determine a signal was artificial in origin?
Humanity has received some odd signals in the past. We've also sent out some signals ourselves.
How could we determine that a signal we'd received was artificial in origin? Or of course inversely, ...
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Are satellites able to stream real-time videos about certain parts of Earth's surface?
Are surface-scanning satellites able to show certain parts of Earth's surface real-time? For example, to follow a person who's escaping.
Somewhere I heard that these satellites are able to make ...
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How is data transferred from interplanetary missions?
I'm trying to find out information about the mechanics of data transmission from planetary probes: techniques, devices, methods, software.
In short, How reliable data transmission is undertaken in ...
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Alternative data transfer channels for inter-stellar probes?
The problem how it is possible to receive data from Voyager I at all is dealt in this question: https://physics.stackexchange.com/questions/13227/how-earth-communicates-with-voyager-i
However, there ...
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