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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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Was the NOAA-N Prime satellite really dropped on the floor?

Recently, Donald.McLean posted this image in The Pod Bay, the site chat room: It's a rather disturbing image once you think about it for more than about half a second. Did it really happen? What ...
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What would be the (most difficult) challenge to make a “10,000 year satellite”?

Update: Bezos' recent Tweeted update on the 10,000 year clock. Also see The Verge's Construction begins on Jeff Bezos’ $42 million 10,000-year clock The discussions associated with the question Can ...
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7answers
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Why do artificial satellites need orbit correction, but natural ones don't?

No matter how much you fine-tune a satellite's orbit up front, it needs periodic adjustments. It's usually done through tiny rocket bursts. The system and fuel to do that costs money and weight, and, ...
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Would we be able to detect an extraterrestrial “Voyager” if it came near us?

Attached to the Voyager probes are the golden records, which are essentially messages-in-a-bottle sent out into the vast sea of interstellar space, containing of course the "message of humanity". ...
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Does a satellite naturally turn in phase with its orbit, always facing Earth?

Assume you want a satellite to constantly point its radio dish towards Earth while orbiting it, or its solar panels towards the Sun if it is instead orbiting it. Is any of the following true about ...
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Is photography from a satellite good enough to make out a person on the ground?

When I first saw Google Maps satellite view many years ago, I remember being greatly impressed (and somewhat surprised) with the image quality, considering the photographs came from up there in space. ...
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Why are the GPS constellation satellites in such a high orbit?

Most satellites are in Low Earth Orbit. Some other satellites are in Geostationary Orbit because their function requires it. The GPS (and other GNSS, e.g. GLONASS) satellites are in a much higher ...
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How does GPS receiver synchronize time with GPS satellites?

GPS satellites transmit time values regularly, but if we put in consideration the time delay between the satellite and the receiver, the time value received wouldn't be accurate insofar as I know GPS ...
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4answers
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What would one need to do to get an amateur satellite into orbit?

I've recently become interested in amateur satellite packet radio, and I've seen that the bandwidth and thus the bitrate is extremely low on most amateur satellites, not even factoring in noise. So I ...
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5answers
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Is it possible to see animals from space?

Will satellite imagery be able to see the backs of big animals such as lions, tigers, elephants, horses or zebras from space when they venture out in the open? I've not been able to find satellite ...
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5answers
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Why didn't NASA use the shuttle to make a profit?

My understanding is the shuttle was designed as cost-effective workhorse, a space-van to ferry cargo up to the ISS, conduct zero-G experiments and put satellites into orbit. So why didn't NASA take ...
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Is it possible to track an object as small as the Tesla Roadster around the Solar System

I have heard that we will soon lose track of the Tesla Roadster launched with the Falcon Heavy test launch. Yet, we know where Voyager is out beyond the Solar System and we followed other satellites ...
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What would be the first noticeable consequences to the general public of widespread satellite destruction?

What would most likely be the first thing I, as an average citizen of a developed nation, notice, if within a matter of hours, all major commercial and government satellites were to be destroyed in a ...
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1answer
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Why were early Soviet spacecraft spherical?

Sputnik's ball shape is instantly recognizable to most of us: I was looking at the Wikipedia page for Luna 1, and saw it was also a ball-shaped spacecraft: Why do these spacecraft have a spherical ...
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1answer
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What is the farthest artificial satellite in orbit in our solar system?

When did we send the farthest satellite and what is its role and name ?
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What is the smallest operational artificial satellite?

Miniaturisation has many advantages, and in recent times, nanosatellites, picosatellites, and femosatellite concepts have emerged. The Wikipedia article on miniaturised satellite has some pointers. ...
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Is there any way to find and track Pioneer 10, 11, and Voyager 1, 2?

The space probes Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2 are the first man-made devices to have escaped from our solar system. The main problem they face is the lack of power source in them. ...
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1answer
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Does anyone who works at SpaceX know the paths of classified payloads?

As SpaceX has launched both NROL-76 and OTV-5, does anyone at SpaceX know the trajectory of the vehicle, or is the falcon upper stage under the direct control of the Air Force?
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Why is the ribbon of decommissioned geosynchronous satellites skewed?

I was looking at this 3D map of satellites orbiting earth and noticed something interesting. Around the green ring of active geosynchronous satellites, there is a ribbon of what I assume are obsolete ...
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What would happen if a satellite took a direct hit from a coronal mass ejection (CME)?

I was wondering what would happen if the average satellite were hit by an average CME. According to wikipedia the average velocity of a CME is 20 to 3,200 km/s. In addition to this it's super-heated, ...
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4answers
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Is there a satellite that tracks other satellites?

Is there a satellite that tracks other satellites, or is tracking always done from ground stations? Ground stations can only see a small part of the sky, so a network of stations would be needed. A ...
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4answers
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Are artificial satellites completely sealed or open to space?

Are artificial satellites such as communication or weather satellites completely sealed or are they open to space? (In either case, why? How are their electronics (un)affected? Presumably they can be ...
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Is the Pi really fit for outer space?

Recently, there has been growing interest in using Raspberry Pis in CubeSats. NASA is even in on the trend. But, considering that outer space is pretty harsh on electronics (i.e. radiation and cosmic ...
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1answer
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Which artificial satellites in lunar orbit are currently active?

Most of artificial satellites of the Moon has depleted their batteries, lost communication, been deorbited or impacted the surface after orbital decay. The list doesn't exactly make it clear which ...
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2answers
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Did Sputnik 1 have attitude control?

The (currently only) answer to Why did Sputnik 1 have four antennas? discusses how Sputnik 1 had four antennas in order to ensure that the Earth would never be in the null of any of its antennas. ...
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What is the oldest orbital satellite we can contact?

Vanguard 1 holds the record for being in space longer than any other man-made object, along with the upper stage of its booster. It was launched on March 17, 1958, but was last heard from in May of ...
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1answer
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How many active or inactive artificial satellites are in Mars orbit?

I just read in the BBC news that four nations have placed satellites in Mars orbit. How many active or inactive artificial satellites are there in orbit around Mars (2014)?
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2answers
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How full is the geostationary belt?

The geostationary ring clearly seen in the above picture looks alarmingly crowded. How full is it? How much space does a satellite in that orbit require to operate safely? Surely, (other) ...
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8answers
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How would a long pole be transported to space?

Can a long pole or a set of poles be strapped to the out side of a rocket (like a bottle rocket)or on the nose as an external payload without interfering with the aerodynamics of the rocket? How would ...
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2answers
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Suppose Zuma wasn't “lost” — what would it take to detect it?

Being a secret government launch, there has been speculation maybe the Zuma satellite wasn't lost, and claims to the contrary are a ruse to throw off parties who'd like to track it. There is possible ...
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2answers
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How does a single rocket place multiple satellites into orbit?

Nowadays, many rockets transport more than one satellite in orbit. But how does a single rocket place multiple satellites into their orbits? Do all rockets which place multiple satellites into orbit ...
19
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2answers
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Can spacecraft be made invisible to stations on Earth?

Can spacecraft be made invisible to ground stations? For example, are spy satellites perhaps equipped with stealth technology to prevent radar tracking? Or is it pointless as they can always be ...
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1answer
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What are the end-of-life options for large classified satellites?

The Delta IV Heavy recently launched NORL-65 to a low Earth orbit. Some of these missions will be in the range of 390 km altitude with circular orbits. Plus, the Delta IV Heavy is a big rocket, with ...
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What was the first programming language in space?

Sputnik 1 was the first satellite in space. Did it have a programming language on board or was it purely analog? in 1949 Von Neumann released the language Short Code. Fortran was invented in 1957. ...
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2answers
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How can any probe be safe at one million degree Centigrade temperature?

Even after going straight inside the sun's corona, how can Solar Probe Plus be safe at the one million degree Centigrade temperature of the sun's corona ?
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1answer
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What is the purpose of the satellite that China is putting in lunar orbit?

I was just reading an article about the satellite that China is putting in Lunar orbit as phase one for their exploration of the far side of the Moon. Is this satellite just to be used as a signal ...
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4answers
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What is the oldest artificial satellite still in use?

Wikipedia states that Vanguard I is the oldest artificial satellite still in orbit. What is the oldest that's still in use?
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Why are photos of satellites most often computer generated?

I like looking at photos of stuff in earths orbit. But when I google satellites I often get a lot of nice but not as exciting CGI. I understand it might be hard (but not impossible) for a satellite to ...
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3answers
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What's the largest aperture telescope sent beyond the Earth-Moon system?

The question and answer about telescopes sent to different planets got me wondering. There are so many solar system bodies that have been photographed by deep space spacecraft, planets, dwarf planet(s?...
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1answer
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How do spacecraft navigate through the Asteroid belt to avoid collision?

Have any spacecraft been lost transitioning between Mars and Jupiter? How do spacecraft navigate that field unscathed as well?
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What's salvageable from a dead satellite?

DARPA has proposed orbital maintenance and salvage robots. I had gathered a list of links that was lost when DARPA rearranged their website. But I was able to find this page: Phoenix Makes Strides in ...
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Passive attitude stabilization with magnets - are there studies based on actual flight data?

Specifically with the small satellite and cubesat people, there is an rather 'old' idea around: Passive attitude stabilization based on permanent magnets. Schematic of the Earth magnetic field lines ...
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Minimum number of satellites to image the entirety of Earth's surface at all times

The simplest solution would be a tetrahedron, but as the satellites all need to orbit in circles, it seems this configuration would only guarantee full coverage at one time. For simplicity, there's ...
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1answer
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What satellites did the Shuttle retrieve from orbit?

Hobbes wrote: The Shuttle was designed for things NASA rarely or never used: [...] The ability to retrieve satellites from orbit was used a few times, but not as often as envisioned. I wasn't ...
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What factors determine whether a spacecraft/probe/satellite uses gyroscopes or propellant thrusters to rotate?

Say I'm designing a probe or satellite. To control its attitude, I can add some gyros, or I can put thrusters on each corner, or I can add both and pick one in flight according to the situation. How ...
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How accurately (maximum possible accuracy) can future satellite positions be predicted?

Agencies/organizations who own/operate satellites want to know their future positions after a certain amount of time. We know that models of satellite dynamics are imperfect and also perturbations ...
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2answers
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Why are obsolete geostationary satellites re-orbited above the geostationary belt?

That seems a bit counter-intuitive, because in an orbit above the belt, the satellite would eventually lose gain velocity, so its orbit would intersect the orbital plane of the geostationary ...
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Why do space agencies invest more in flyby probes rather than orbiting satellites?

First of all, the title is just an assumption based on a very small sample size of the Voyager spacecrafts and New Horizons. We have orbiters around the moon and Mars because we had/have plans to land ...
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Do companies/governments ever sell satellites that are already in space?

Do companies/governments ever sell satellites that are already in space to other companies/governments for use? I'm wondering about the sale of the actual physical satellites. Has it ever happened? Is ...
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Can you make out the shape of the ISS with the unaided eye as it passes overhead?

Someone claimed to me that they could see the actual shape of the ISS as it passed overhead without use of any optical device. I would think this isn't possible since it is only about 100 meters wide ...