# Tag Info

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Apollo 11 mission had two modules Lunar module - which descent to moon carrying two astronauts command / service module- CSM was designed to return astronauts from the lunar surface on a direct-descent mission to earth and splash down. Direct telecast from the Command service module is not possible but CSM stored the recording of conversation which is ...

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The signal from the Moon was received using giant parabolic antennas, e.g. the 64-m dish at the Parkes observatory. These have very good sidelobe rejection so they won't pick up any Earthbound signals. Despite the space race, relations with their biggest enemy were good enough that the Russians shared Luna 15's flight plan with the Americans when this ...

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The Arecibo raqdio telescope has a $300\ \mathrm m$ diameter mirror. Let's consider a radio wavelength of $3\ \mathrm{cm}$ ($10\ \mathrm{GHz}$) for convenience of arithmetic. That gives a diffraction limited beam width of $100\ \mathrm{µrad}$, so at 100 light years, the signal would be spread over an area $10^{14}\ \mathrm m$ across. The Arecibo signal was ...

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From ArsTechnica: Late Tuesday night, scientists at NASA's Jet Propulsion Laboratory sent their final data uplink to the Opportunity rover on Mars. Over this connection, via the Deep Space Network, the American jazz singer Billie Holiday crooned "I'll Be Seeing You," a song that closes with the lines: I'll find you in the morning sun And when ...

45

Mission Control in Houston had a radio communication with the Apollo capsule as well as the Moon lander. A phone connection between the White House and Ground Control was established and connected to the radio transmitter and receiver. Of course the Deep Space Network with its three large antenna stations in Goldstone, Madrid and Canberra had to be used. To ...

39

From this article, and this article: Live television was transmitted from the moon to 3 grounds stations, two in Australia and one in California. The signal was converted to a standard broadcast signal and then sent to Houston, via, satellite, landline or microwave antenna. These graphics show the path of the television feed. Bottom line is, the ...

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Communication system: The radio communication system of Voyager 1 was designed to be used up to and beyond the limits of the Solar System during the extremely long flight of this space probe. The communication system includes a 3.7 meter diameter parabolic dish high-gain antenna to send and receive radio waves via the three Deep Space Network ...

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New Horizons was hidden behind the Sun a few days after the flyby, from January 4th to January 7th. Almost as soon as the encounter and earliest downlinks are over, New Horizons will go into solar conjunction from January 4 to 7. I asked Alice Bowman what implications that has for the mission, and she replied: "During solar conjunction, the downlink data ...

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He replied that we actually received the signals in just 1-2 seconds with the help of MarCO CubeSats. Later on followed up with confusion from other users with his statement and asked for clarification, he then mentioned that it is relating to quantum entanglement for communications. This is nonsense; the MarCOs received the signals in 1-2 seconds, but ...

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@SteveLinton's answer is excellent and I'll just confirm below that its logic and numbers are correct. Then I'll show that you can do it optically as well, but with 10 meter telescopes instead of Arecibos you run into a challenge because each individual light photon carries most of the total received power per second. Radio From this answer: One ...

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Starlink (and other satellites) categorically do not have exterior lights or illumination, that would be a waste of power for no particular benefit. The reason that we can sometimes see satellites or other spacecraft at night is because the spacecraft is still exposed to daylight. Here is an image describing this phenomena: (image credit: Gary Meader; ...

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Spacecraft are placed into the orbits that they need to be in, given the objectives of the mission and the constraints during design. Nothing in space is arbitrary, since there is so much at stake if something goes wrong. In fact, GEO is not a particularly special place for a space telescope and several telescopes are placed (or are planned on being ...

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No, it's not feasible. The fundamental problems that prevent this are: The Pioneers do not have enough power to operate the transmitter, due to corrosion of the thermocouples The Voyagers and Pioneers, even at full power, use very low power transmissions The Pioneers would need to be able to receive and obey instructions to aim for a Voyager The craft are ...

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It can be seen through this Wikipedia article that all communication with the Apollo missions was done at about 2.2 GHz, which is well above the frequency that reflects on the Ionosphere (No higher than about 30 MHz). FYI, the Gemini radio system also used frequencies in the UHF range, although it included some VHF, and even some HF. The HF/ VHF signals ...

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Most likely no. Voyager downlink communication (via its radio link to NASA's Deep Space Network (DSN) is not continuous. You can check the contact schedule at this Voyager site. If everything looks fine during one DSN contact period, and then at the next contact period there's no signal at all, there are myriads of possible causes, ranging from failure of ...

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No. "200 km" is the shortest distance (actual ISS altitude varies but is closer to 400 than 200 km), but at that distance you're far outside the main lobe of the ground station antenna. Cellular traffic is usually at an elevation below the antenna (which sits on a tower), so the antenna main lobe is aimed in the horizontal direction or slightly below. When ...

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It absolutely could happen, but it would require a more precise pointing than New Horizons has. Lasers of some kind are the best for the high data resolution. The spacecraft to most heavily use lasers in communication is the Lunar Reconnaissance Orbiter. It has also long been talked about as a goal for a Mars communication satellite, which would allow for ...

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In addition to the limited downlink time due to it being hidden behind the Sun, it should be noted that the New Horizons team is prioritizing downlinking the metadata of each of the images. This will allow them to prioritize downloading the images that actually have something interesting in them, and deprioritize the images that will be of blank space. Keep ...

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If you listen to live (or recorded) ISS to ground conversations you will find that the astronauts are human, and have perfectly normal conversations when not specifically running through mission checklists etc. These conversations include banter, birthday wishes, conversations about the weather (yep - seriously) and any manner of normal topics. I couldn't ...

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Spacecraft that take pictures take them similar to a digital camera. However, the camera is very far away. Similar to downloading a movie off of a website so you can watch it on your local device, it takes time to transmit those images. However, because the distance is so far away, it can take a lot of time to download the images. The images reside on a ...

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According to NASA's Space Educator's Handbook: As the men in Apollo 13 experienced what no men had undergone before, millions followed the developing drama by radio and television in public squares, private homes, schools, offices and factories. Pope Paul, at an audience in St. Peter's Basilica for 10,000 Romans and tourists, said "We cannot forget at ...

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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-change “symbols”, and you want to find the time-pattern of those: symbol lock. But those are not yet bits because the coding works in blocks of bits. Once you ...

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The difference between 10 W at 350,000km, and 1,000 W at 1km is 131 dB. If the pranksters on Earth used a directional antenna like the Ham radio operators shown below, the ratio would be even higher because that thing has much more gain than the Apollo antennas from the orbit and surface of the Moon. It would only take a tiny bit of random or isotropic ...

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No, absolutely none. Even assuming Pioneer 11's transceiver still works, and there's no reason to believe that, that image you attach of distances between the three probes isn't showing it proportionally correct, since it's merely an approximate slice of euclidean space and is not axially aligned with anything to correctly appreciate distances involved. So ...

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Yes, the Earth can send Voyager 1 a message as easily as we can receive a message. There are a few differences between the uplink and the downlink paths. We cannot upgrade the radio on Voyager 1 to newer equipment (but an upgrade to the Earth station is equally beneficial), The gain of the antennas on the spacecraft and on Earth are constant, and the free ...

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Apparently not: I like this Quora answer. Here's part of it, the rest is worth reading as well: No experiment conducted using entangled photons has ever demonstrated faster than light communication! There have been many such experiments. They were not looking for faster than light communication. They were testing quantum mechanics against Einstein's ...

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Let's compare with 4G, for which I could find some numbers: Your cell phone is transmitting with speeds of up to 50MBps with a maximum of 1 Watt (can be as low as a few µW!), using a tiny antenna that is often obscured by water bags (human flesh and organs), rocks, buildings, trees, etc. Let's compare this with Mars Express, for example: its maximum ...

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Maybe. Let's start with a known system that can communicate with Earth directly from Mars' surface: Curiosity's low gain antenna. This is driven by a 17 W transmitter and has 6 dB antenna gain (so 48 dBm), which is enough to communicate at low speeds (10-50 bps) with a 34 m DSN antenna on Earth. Compare this to a cell phone: this has a 3 dB antenna gain ...

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It's a great question! Trajectory To get a few decades more out of them, you can launch Voyagers 3 and 4 sometime around now and get by with a maximally-boosting flyby of Jupiter since you wouldn't target Saturn as well. If you had to wait for Jupiter and Saturn to line up with the original pair's trajectories again, it would be too long of a wait. ...

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It wouldn't need to turn as fast to stay focused, maybe increasing the lifetime of its reaction wheels. On Earth when you "turn" a telescope, you are really keeping it pointed in one direction! It's the Earth that's turning, and you have to turn the telescope mount to keep the legs pointed at the ground. It's the same thing as having to move the antenna to ...

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