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00:00From the moment a rocket lifts off, it is tracked and monitored.
00:15All vital performance characteristics are relayed back to the ground via telemetry.
00:24At huge distances a probe must be able to communicate.
00:30On Earth to pick up these signals, we use parabolic dishes.
00:34They range in size from small domestic units for television reception
00:39to the giants of the deep space network.
00:42Without these, almost any space flight would be pointless.
01:00The very first artificial satellite, Sputnik, was designed with four whip antennas and two radio transmitters.
01:20Soviet engineers saw its main function as announcing to the world that it was there.
01:33It transmitted a continuing series of beeps.
01:36Ham radio operators around the world could detect the signal.
01:42Very few realized that the beeps varied in duration according to the temperature and pressure within the sphere.
01:48The signals could also be analyzed for clues to the ionosphere's electron density.
01:52Soon cosmonauts and astronauts were orbiting the planet.
02:09When John Glenn made the Mercury program's first orbital flight,
02:13eighteen different tracking and communications posts were set up along his spacecraft's ground track.
02:20As well as local staff, NASA provided each ground station with its own capsule communicator,
02:27a flight engineer and a flight surgeon.
02:29Special tracking ships were deployed to maintain communications and monitor telemetry while the spacecraft was crossing the ocean.
02:40But even so, the network had blind spots where the spacecraft was out of reach.
02:53For the Soviets, communication was even more difficult.
02:56During their early space flights, there were no tracking ships and their terrestrial stations were all in the Soviet Union.
03:11When the Soviet Union launched Lunik 1 in 1959, it was intended to hit the Moon.
03:19It missed and became the first craft to achieve solar orbit.
03:22Because it required special tracking infrastructure and was not monitored outside Russia,
03:29many in the United States refused to believe that the spacecraft had even been launched.
03:36At the time, the world's largest radio telescope was the Mark 1 installation at Jodrell Bank in the UK.
03:42Soon, the Russians began sending detailed information about finding their probes to Jodrell Bank as a means of independently verifying their missions.
03:53In the early days of the space race, the Soviet Union had big plans for deep space missions.
03:59In 1959, construction work began on the Pluton facility in the Crimea.
04:10Though the Soviets did not enjoy the financial resources of the United States, they were not lacking in enterprise.
04:16The Pluton receiver consisted of eight dish antennas welded onto pieces from the hulls of two war surplus submarines.
04:20They were mounted on a steerable frame made from the trusswork of a railway bridge.
04:31To point the dishes with accuracy, the designer, Evgeny Gubenko, employed the mechanism from the gun turret of a scrapped battleship.
04:40The system worked well and remained in service till 1978.
04:51It had become clear to the space powers that communications support for low-Earth orbiting satellites was very different to that needed for probes travelling into deep space.
05:02Deep space missions require much larger, more sensitive dishes with powerful transmission capabilities.
05:11Yet these probes' position in the sky changes more due to the Earth's rotation than it does because of the craft's speed.
05:19So while the dish has the point with great accuracy, it does not have to move very rapidly.
05:24Satellites in low-Earth orbit pass close, so a smaller dish is adequate.
05:31But it must move rapidly to maintain a precise focus on its target craft.
05:36In the United States, corporations were taking an interest in a huge new type of satellite.
05:43Researchers were interested in using an orbiting balloon to relay radio signals across continents.
05:48Project Echo launched its first inflatable satellite in 1960.
06:06This is President Eisenhower speaking.
06:09A telephone call from President Eisenhower was relayed from Washington to California
06:13by bouncing signals off the balloon which acted as nothing more than a reflector.
06:21In 1962, US phone company AT&T built Telstar.
06:26It was the first electronic relay satellite.
06:35Launched by NASA in July 1962, Telstar was the first commercially-funded satellite.
06:40Europeans tuning in to see President Kennedy got baseball and then the presidential press conference.
06:50I understand that part of today's press conference is being relayed by the Telstar communication satellite.
06:57Then French singer Yves Montand sang a song to the US.
07:00As far as it went, it was a success.
07:13But Telstar's low orbit meant it was only available for 20 minutes every two and a half hours.
07:18And Telstar's life was cut short as a result of the Cold War.
07:21Both the Soviet Union and the United States had been detonating thermonuclear weapons above the atmosphere to determine whether this was a viable anti-missile strategy.
07:34From tests in the Pacific they discovered that an immense pulse of gamma radiation triggered positive ions and recoil electrons that took out electrical systems in Hawaii and New Zealand, destroyed at least three satellites and damaged several others, among them Telstar.
07:52In October 1963, U.S. President John Kennedy added his signature to a treaty with the Soviet Union banning nuclear testing in space.
08:15The first telecommunications satellite that resembled today's technology was Intel Sat-1, also known as Early Bird.
08:27It orbited above the equator at the same rate as the Earth's spin, which allowed it to hold a static position.
08:34It could relay one TV channel or 240 telephone calls.
08:38It was the beginning of the space business's most profitable industry.
08:46Estimates put satellite telecommunications revenues for 2019 at 2.4 trillion U.S. dollars.
08:56Geosynchronous orbits make ground stations much simpler, without the need to track a target across the sky.
09:02Today there are at least 240 active satellites in equatorial orbit at geosynchronous altitudes.
09:12Not all are communications platforms.
09:15Weather satellites also find this orbit useful, having an uninterrupted view of a complete hemisphere.
09:25The craft must be carefully spaced to avoid collisions and radio frequency interference.
09:29The International Telecommunications Union coordinates the orbital slots and frequency allocations.
09:36And satellites nearing the end of their useful life must retain enough fuel to boost themselves into a graveyard orbit to prevent overcrowding.
09:45There is clutter caused by spent upper stages and old satellites.
09:49Another highly specialized group of communications satellites is also stationed in geosynchronous orbit.
10:03NASA currently operates 10 tracking and data relay satellites, TDRUS.
10:08Originally designed to provide a continuous communications link for shuttle missions, TDRUS supports many near-Earth satellites as well as the International Space Station,
10:22the Hubble Space Telescope and some military applications.
10:26Similarly, ESA has launched two of what will be a group of four data relay platforms to provide a continuous link with near-Earth satellites.
10:36Instead of transmitting to ground stations, only visible for brief parts of every orbit,
10:42many satellites now send signals up to a data relay spacecraft that can see it for half of each orbit.
10:47A network of relay satellites around the globe gives continuous coverage.
10:57All major space agencies have been experimenting with data transmissions via lasers,
11:03but the EDRS system is the first commercial application of optical communications between spacecraft.
11:08Current laser communications techniques between satellites deliver data at 1.8 gigabits per second,
11:1830 times greater than conventional radio links.
11:21However, weather-related problems inhibit reliable laser connections between spacecraft and Earth.
11:27Transmission back to the ground is via microwave radio in the KA band.
11:33While this is fast, it is still slower than the laser data rates,
11:37but the signal can be split into several streams and sent simultaneously.
11:46Europe's Copernicus system is a major beneficiary of the near real-time data available via the EDRS system.
11:56Copernicus is an Earth observation program relying on a series of Sentinel satellites
12:01that send back continuous streams of data about the land, the oceans and the atmosphere.
12:08The Copernicus program is not a limited project.
12:12It is designed to collect authoritative data about planetary changes over the long term.
12:18To do this, the Sentinel satellites are in low north-south orbits,
12:22allowing them to see the Earth's entire surface every 24 hours.
12:26This polar orbit is common to every Earth-observing satellite.
12:31But not every satellite has access to the EDRS communication system,
12:37nor do they generate the vast amounts of high-resolution data that requires it.
12:42Most satellites following a polar track rely on the polar-receiving installations
12:47that they pass above every orbit.
12:50On the Norwegian archipelago of Svalbard,
12:53the SvalSat installation has 31 radomes to track and download data from satellites in polar orbit.
13:00To relay the information to the outside world,
13:04twin fibre-optic cables, each handling 10 gigabits per second,
13:09connect Svalbard to the Norwegian mainland.
13:11Konigsberg, the company that operates the facility for the Norwegian government,
13:17runs a smaller station in Antarctica.
13:20There are close to 1,900 operational satellites in Earth orbit,
13:26with a further 3,000 still orbiting as space junk.
13:30But there are as many as 20,000 fragments from spent boosters
13:36and debris from collisions that must be tracked.
13:38Operational satellites are routinely moved when an object approaches on a dangerous course.
13:46If this picture appears crowded, it is about to become a lot more complex.
13:52The US Federal Communications Commission recently gave rocket company SpaceX approval
13:58to launch 12,000 new satellites for its Starlink broadband internet service.
14:03Current satellite internet services rely upon a very few large platforms in geosynchronous orbit.
14:13Typical users are in remote locations,
14:16and while costs are coming down and speeds are improving,
14:20latency, or response time, is sluggish.
14:22The Starlink model has thousands of small satellites in low Earth orbit,
14:29cross-linked via high-speed lasers.
14:32The satellites will be able to adjust their orbital path autonomously to avoid collisions.
14:36The company launched its first batch of test satellites in May 2019.
14:51The second group, launched in November 2019, consisted of 60 operational satellites.
14:56For one company to increase the number of functioning spacecraft by a factor of six, cost is critical.
15:10The satellites are being mass-produced in a flat-pack form with a single solar panel.
15:1460 will stack neatly within the fairing of a Falcon 9 launch vehicle.
15:23The Starlink satellite design is pushing the latest technology to its limits.
15:28Links to the ground are via a phased array, enabling a steerable beam without the need for moving parts.
15:35Maneuverability comes from a Hall effect thruster using Krypton as its propellant.
15:41When released from the booster, the satellites do not require dispensing hardware.
15:46They are pushed away by springs in apparently haphazard fashion.
15:50At this stage, they can even bump each other and are designed to withstand the impact.
16:00Quickly, the satellites orientate themselves and begin spreading along their orbital path.
16:04At this point, they can be seen in the pre-dawn or just after sunset.
16:10Research astronomers are not happy about the huge number of satellites soon to be in orbit.
16:17By 2024, there should be 11,927 Starlink satellites orbiting at seven different heights.
16:26The only satellite constellation remotely similar is the Iridium NEXT system with 66 satellites cross-linked via the KA band.
16:36They are designed to provide global cell phone coverage.
16:40And in 2018, the Iridium company finished the replacement of all its first generation spacecraft.
16:45The upgrade cost Iridium $3 billion.
16:54For 200 times more satellites, SpaceX has budgeted $10 billion.
17:03Iridium had to pay Thales Alenia to design and build 81 satellites.
17:07There are spares both in orbit and on the ground.
17:15And it had to pay SpaceX to launch those satellites in batches of 10.
17:25With Starlink, the company will take advantage of its own drive to reduce expensive launch services.
17:30SpaceX builds its own satellites and its own rockets, so will only pay cost for hardware and delivery.
17:43Recovery of first-stage boosters is now routine, which takes a large chunk out of launch costs.
17:49And the protective fairings, always regarded as throwaway items,
17:53are now fitted with steerable parachutes for retrieval and reuse, saving a further $5 million per flight.
18:03What will give Starlink its edge is its improved latency.
18:07In most cases, the system should give even better latency figures than fibre-optic connections on the ground,
18:14let alone the half-second delay built into systems that send signals 35,000 km up to and back from geosynchronous platforms.
18:23For stock markets reliant on high-frequency trading, microseconds make a significant difference.
18:35SpaceX believes people around the world will want the service.
18:41OneWeb and Amazon's Project Kuiper have announced plans to develop their own low-Earth-orbiting broadband systems.
18:47But with just the smallest fraction of the Starlink constellation in orbit, astronomers are starting to worry.
18:54Survey telescopes that use time exposures to map the skies looking for anomalies,
19:01like approaching asteroids or exploding stars, have recorded dusk and dawn images marred by Starlink satellites.
19:07Researchers from the Large Synoptic Survey Telescope, currently under construction in the Gilean Andes,
19:14have run simulations suggesting that as the Starlink constellation takes shape, certain observation times will be unproductive.
19:23Yet the Starlink venture itself is still a risk.
19:31Satellite businesses like Teledesic and Skybridge, both with big plans, went under.
19:38And SpaceX leader Elon Musk admits that success with Starlink is far from a sure thing.
19:43Communications with very distant, exploratory spacecraft are governed by different parameters.
19:57The New Horizons probe, launched in 2006, is equipped with the most advanced digital technology ever to reach deep space.
20:05While its primary target was the dwarf planet Pluto, it passed Jupiter in 2007 for a gravitational boost to its speed.
20:16At Jupiter, a mere 2.3 billion kilometers from Earth, it transmitted images at 38 kilobits per second.
20:25That's slightly slower than an old acoustic telephone modem.
20:29At these distances, signal strength from New Horizons was weak, and only the 35 and 70 meter dishes in NASA's deep space network were useful receivers.
20:42Even so, the data rate was slowed to deliver a coherent signal.
20:49Sending commands to the spacecraft is an exacting process.
20:53All instruction code is thoroughly reviewed by different teams before being tested on a simulator.
21:00Only then are they sent to the spacecraft.
21:08Because the environment around Pluto was so poorly understood, controllers on the ground relied on preliminary images returned by the spacecraft to make a hazard search.
21:19Distant encounter observations commenced seven months before its close pass.
21:23As New Horizons approached Pluto in 2015, it had at least 16 different science objectives, along with spacecraft control and data management procedures, all pre-programmed.
21:37There could be no last minute corrections.
21:41The spacecraft was traveling at more than 49,000 kilometers per hour, and signals from Earth took close to four and a half hours to reach the New Horizons probe.
21:53During the critical close approach, there was a 22 hour radio silence because the spacecraft could only make its scheduled observations with its high gain antenna angled away from the Earth.
22:11Everything was committed to the 8 gigabytes of storage in the primary data recorder.
22:19To retrieve that data took 16 months.
22:22At a distance of 4.7 billion kilometers, the New Horizons data rates were down to 2 kilobits per second.
22:32Only the 70 meter dishes in NASA's deep space network could detect the signal, and they could not work exclusively with New Horizons.
22:40New Horizons kept going into the icy debris field known as the Kuiper Belt.
22:49Even as it was still transmitting data from its Pluto encounter, engineers on the ground formulated a series of course adjustments that would take it past object MU69.
22:59The first time a probe was targeted at a body unknown when the craft was launched.
23:10In January 2019, New Horizons encountered the Kuiper Belt object Arrokoth, formerly known as Ultima Thule.
23:19At a distance of 6.6 billion kilometers, data from the spacecraft took 6 hours and 7 minutes to reach Earth,
23:26and the data rate had dropped to 500 bits per second.
23:31It's still trickling in.
23:37Finally, the most distant probe is Voyager 1.
23:41It was launched in 1977, and is now outside the solar system at a distance of 22 billion kilometers.
23:49The probe transmits data as it is registered,
23:52and the deep space network tries to gather at least 16 hours per day of the data stream that comes in at 160 bits per minute.
24:03This is roughly equivalent to a telegrapher sending Morse code.
24:07Be okay with Bertie to take care of your IDM account and can see your body birch.
24:10Here it is.
24:11A margin of time is locked in your pocket, and go see your chest-hit personas.
24:14The amiiboian network journaled by OwsonHeunz,
24:16and were not my po turm thats tricking out.
24:18The Booge by
24:31The According state Winter
24:32Code and Per noticesBLES
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