# Tag Info

29

In order to answer this question, I tracked down Michael Lammers who the Flight Director for the ISS and he kindly offered to speak to me on the phone about ISS communications. (He is also a super nice guy) He said that almost all of the ISS Command and Control, Voice Communications, as well as science downlink, goes through TDRS with the Ku-Band handling ...

20

Yes, Soyuz spacecraft can serve as a lifeboat and return a single crew to Earth. From Anatoly Zak's Russian Space Web page: In case of emergency on the station, the Soyuz can be sent up unmanned or piloted by a single cosmonaut to serve as a lifeboat; or be used as an unmanned cargo ship to return 250 kilograms from orbit. If for some reason contact ...

16

The legend at the bottom describes red cloud as "Зоны НИП", which is "NIP" (pronounced "neep") zones/areas. Quick googling reveals that here НИП is decoded as either "научно-измерительный пункт" (Scientific Measurement Point/Station) or "Наземный Измерительный Пункт" (Earth[-based] Measurement Point/Station). Both unreferenced. So, basically, this is area ...

11

Open area, broad horizon, meaning either hilltops or plains; not valleys. good power infrastructure available. Network and other infrastructure a boon. reasonably stable seismically. Also, due to location, landslide risk must be taken into account. reasonable access and servicing logistics, staff availability. distant enough from other ground stations not to ...

10

ISRO's MOM lifting off (credit ...

9

Spacecraft tracking in Apollo was done by the Unified S-Band (USB) system. It was called "unified" because it combined voice, tracking, telemetry, and computer commands. There was a completely different communication system (VHF) which did voice and television, but not tracking, and is not related to this question. Apollo 8 was an early manned flight, ...

8

I would translate "НИП" ("наземный измерительный пункт") as "ground telemetry station". Answering what happens when the ISS is inside it When the ISS is within the area covered by НИП, direct communication is possible between the Russian flight control and the Russian segment of the OSS (at other times communications are relayed via Luch satellites). ...

7

During Project Mercury, NASA's communication network was new, and many of the ground stations did not have dedicated voice communications links back to Houston, so each site needed its own CAPCOM, as described in this QA. During Gemini the network was upgraded; many of the ground stations could provide direct voice links to Houston, but others could not, as ...

7

Removing Radio Frequency Interference (RFI) can be quite a challenging issue, but it can be solved. There's a number of things that should be done to minimize the effect of this noise. A basis for this can be found from the American Radio Relay League (ARRL), but some of it is just from experience. All of your sensitive equipment should be in a Faraday cage,...

6

This is an interesting question! There are (at least) two communications issues to consider. One is signal strength as the question asks about, the other is latency or delay. But the tl;dr is that this won't work using standard WiFi or cellular data equipment because the antenna would have to be kilometer sized, and the delays are incompatible with the ...

5

Most probably no. I couldn't find any list of stations on duty, but it can easily be "proven" that it wasn't possible. On one hand, all landings happened shortly after local sunrise, and all within a 54° range (between the 23W of Apollo 12 and 30E of Apollo 17) List of Apollo landing sites. As the moon is tidally locked to the earth, those 54° correspond ...

5

Based on the information in the question, which is nearly nothing, let's assume the ground stations and satellites are all using circular dish antennas. Then we can use physics to approximate the radiation patterns with an Airy function. $$I(\theta) = \left(\frac{2J_1(x)}{x} \right)^2$$ $$x = ka\sin(\theta)$$ where the wavenumber is given by $k = 2\pi/\... 5 Supplemental answer: Three sites in Australia were used to communicate with Apollo. Tidbinbilla (now called Canberra DSCC) Designed and continues to be used for tracking and communications of deep-space probes by NASA's Jet Propulsion Laboratory. One of three locations of the Deep Space Network (DSN). Located in the Australian Capital Territory, which ... 5 Talking about India It has one DSN station with S/X band support with 11,18 and 32m antennas. As earlier answer marked, except for time critical tracking and control operations, data set collected over series of passes or a larger time interval can suffice orbit determination needs. During critical mission phases of important missions like MOM, ISRO does ... 4 Many universities might be on the cheap spaceflight waiting list and might be building their own CubeSats or similar microsatellites that could potentially fly on the cheap as secondary payloads, but so far weren't as lucky yet. Such waiting lists can stretch for many years. So they would want to be prepared and with a ground team having some hands-on ... 3 Naive maybe, but your Google Maps picture appears to be correct. This page goes into the history of the Parkes Telescope. It's clear that it has never been moved and is at the Visitor Center location on the Google map. The 1965 map on this page shows the location of Honeysuckle Creek to be due south of Canberra, as shown on your Google map. So the ... 3 It depends on what you want to do exactly, but a few rules of thumb: Typically you want the inclination to be about the latitude of where you want to have coverage. The inclination plus ground swath must cover the area you want to cover. You can never see the poles from the ISS, for instance, for that you need a polar orbit. For a near equatorial orbit, a ... 3 if you have lat/long, you also need altitude of both. if you have Cartesians G for the ground station and S for the satellite, create the vectors$\vec z=0 \to G$, and$\vec s=G \to S\vec z$is the zenith (going straight up) at the ground station. find the "zenith angle" of the satellite, by finding the angle beetween the vectors$\epsilon=acos\left(\...

3

If I understand your question correctly, no. The key reason is that NASA doesn't have "bases" the way the various defense services do -- nobody lives on-site at any of the NASA centers, even the fairly remote ones. Thus, the only services provided are typical of large office campuses: cafeteria, gift shop, etc.

3

The relevant standards body is CCSDS (the Consultative Committee for Space Data Systems). They publish a set of "Blue Books" containing recommended interfaces and protocols for telemetry formatting, data compression, encryption, and so forth.

3

A satellite itself which is on an orbit high enough to not interact with the atmosphere is essentially maintainance-free. Without atmospheric drag it won't need any course corrections to maintain its orbit. It just stays there indefinitely. Now about it's operation: This really depends on what the satellite is doing. Do the instruments need regular ...

3

This is necessarily a short answer, I don't doubt there will be other more extensive answers later. The location of a spacecraft in space is changing due to gravity forces and perturbations from drag and solar pressure. The location of DSN stations in inertial reference frame is not constant either. Earth's orbital motion is the first component to consider....

2

I couldn't comment on the question due to low reputation. So, I'd first like to clarify that Local Horizon frame and Long, Lat, Radial distance are two entirely different frames. Local Horizon frame would be Earth-surface-centered (at Ground station) and principle axes being one towards local east (reason for the name 'Local horizon) , Other towards zenith ...

2

From page 144 of Yuen (1983), "Deep space telecommunication systems engineering," Plenum Press, The transmitted ranging signal is generated by coherent frequency division from the frequency reference used to generate the uplink carrier. Usually a code consisting of a succession of frequencies is generated, starting with approximately 1 MHz and decreasing ...

2

Juno was placed in hibernation (https://www.nasaspaceflight.com/2016/07/nasa-junos-arrival-jupiter/) during its trip so contact would have been sporadic. New Horizons used a similar approach: Heading into its first long hibernation cycle, New Horizons sent beacons once a month, requiring virtually no support for most of the time, decreasing time ...

2

members log in via the internet and then reserve a time slot on whichever station they would like to use Yeah,that's the idea.SatNOGS is primarily designed to receive data. In most jurisdictions receiving data is allowed even by non-licensed individuals. But.. having said that, if a station owner needs to send data to a satellite and has the needed ...

2

TL;DR: It should be possible to create a reliable connection between a ground station and a satellite in theory, given all assumptions in this post. However practically the fact that LEO satellites are moving quite quickly, and the need to track these with a motorised antenna, which means that there will be "gaps" in the link, when the antenna need to ...

2

For a minority of missions, yes. Most deep space missions stay in/near the plane of the ecliptic so they're visible from a large range of latitudes. But the Voyagers are at significant angles to the ecliptic, which reduces the amount of time they're visible from wrong-hemisphere DSN stations (or blocks some stations completely, depending on the exact ...

2

According to CHEOPS Launch and Operations, the plan is to use the ground stations at Torrejón de Ardoz (east of Madrid) and Villafranca (at the European Space Astronomy Centre, ESAC, west of Madrid). The sequence of ground passes includes 5 to 6 daily passes over the G/S of Torrejon (or Villafranca, since the MOC plans to use both of them depending on ...

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