A replica of Asterix.

A-1 was the first French satellite, launched on 26 November 1965 from the soon-to-close Hammaguir launch site in Algeria (which had gained independence from French rule a few years earlier).

The original designation of A-1 was later changed in honour of the cartoon character, Asterix (although it had almost been called Zebulon or Zebby, after a puppet from the telelvision show The Magic Roundabout).

With the launch of Asterix, France became the third country to launch its own satellite, and the sixth to have a satellite in orbit (the UK, Canada and Italy had satellites launched previously on American rockets).

Asterix had been developed as part of a kind of internal French space race. It was built and launched just ten days before the FR-1 satellite was launched on an American Scout rocket.

Weighing 42 kilograms, the satellite was a distinctive striped fibreglass spinning-top shape half a meter in diameter, the black stripes to provide passive thermal control.

Intended to test the French Diamant rocket as well as take measurements of the ionosphere, the satellite unfortunately transmitted for just two days (alternate reports suggest that it failed to transmit altogether).

Asterix-1 is still in orbit today and is expected to remain there for centuries to come.

Depiction of a US-K satellite.

Cosmos 2222 was launched twenty years ago on 25 November, 1992 from the Plesetsk cosmodrome.

The 1900 kilogram US-K model satellite was part of the Oko (eye) program, which were intended to identify ballistic missile launches through infra-red detection of their exhaust. To detect these launches the satellites were equipped with a distinctive telescope equipped with a four metre sunshade.

Cosmos 2222 ceased functioning in December 1996, but remains in orbit today, along with the Molniya rocket body that launched it.

The satellites held flashing lights to indicate their position relative to the surrounding starfields and thus used to measure the position of points on the earth’s surface to within a few dozen meters.

Still in orbit today, Cosmos 312 is accompanied by the rocket booster that launched it.

TIROS 2

On 23 November 1960 the TIROS-2 satellite was launched from Cape Canaveral, Florida, aboard a Thor-Delta rocket. Also known as TIROS-B, the satellite’s name indicates that it was the second Television InfraRed Observation Satellite.

The TIROS program was NASA’s first step in using satellites to study the earth – meteorology being the most promising application. TIROS-2 had two television cameras for imaging cloud cover, as well as radiometers for measuring infrared radiation from earth and the atmosphere. It was the first satellite to make infrared observations.

The craft was a 127 kilogram, 18-sided right prism 107 cm in diameter and 56 cm high constructed from aluminum alloy and stainless steel and tiled with 9260 solar cells which charged its nicad batteries.

Magnetic tape recorders stored photographs while the satellite was out of range of the ground station network.

TIROS-2 used five diametrically-opposed pairs of solid-fuel thrusters to maintain its spin rate. Its axis could be oriented with a high degree of precision by the use of a magnetic attitude control device – 250 cores of wire wound around its outer surface.

The spacecraft relayed thousands of pictures containing cloud-cover views of the earth until 22 January 1961, when the scanning radiometer began to deteriorate. It was operational for 376 days in total.

TIROS-2 remains in orbit today, with some associated debris.

Watch a news clip about the launch of TIROS-2 here:

The Skynet program was begun after Lord Mountbatten recommended that the three armed forces use a single method of communication, and the satellite was intended to provide secure voice, telegraph and fax. Two ships, Fearless and Intrepid were fitted with 2 metre dish stations to work with Skynet 1.

Launched on 22 November 1969 from Cape Canaveral aboard a Delta M rocket, Skynet 1A was the second geostationary military satellite, first geostationary military communication satellite and the third geostationary satellite.

Launch of Skynet 1A

Placed in orbit over the Indian Ocean to provide communication to forces in the Middle East (a secure link between Britain and Singapore?), it is believed to have operated for less than one year, seemingly because of a failed travelling wave tube amplifier.

Skynet 1A is still in orbit today, having drifted to the “geostationary graveyard” at 105 degrees west. It has a lifetime estimate of greater than one million years. The rocket body that launched it can also be tracked.

Injun 4 (Image: Gunter’s Space Page)

The “Injun” satellite series was developed at the University of Iowa by James Van Allen (and his team of “Injuneers”), launched between 1961 and 1974 to study radiation and magnetic phenomena in the ionosphere and beyond. Injun 1 was the first satellite developed by a university.

They notably monitored radiation from the Starfish Prime high-altitude nuclear test and mapped the Van Allen belts.

The last three of six satellites in the Injun series were launched by NASA as part of the Explorer program, thus Injun 4 is also designated Explorer 25.

Originally, Van Allen had intended to name the first satellite of this series Hawkeye, for Iowa’s mascot and football team, but to avoid confusion with the new Hawk missile, he named it Injun, inspired by the Cajun sounding rocket and Mark Twain’s character Injun Joe.

The name Hawkeye 1 was later used for Explorer 52 (approved by the NASA Project Designation Committee), the term Injun having received just one letter of complaint.

Explorer 24

Launched on a Scout rocket from Vandenberg Air Force Base on 21 November 1964, the 40 kilogram Injun 4 satellite was an Archimedean solid, faceted with pentagons and hexagons, with an equatorial band.

It carried a companion satellite in a capsule on top – a four meter inflatable sphere named Air Density Explorer (Explorer 24) (see the second and third image on this page).

Explorer 24 was 3.6 m in diameter, built of layered aluminum foil and plastic film, and was covered with 5.1-cm white dots for thermal control.

It reentered the earth’s atmosphere on October 18, 1968.

Cutaway showing Explorer 24 inside Injun 4

Data from Injun 4 ended in December 1966.

Injun 4 remains in orbit today, along with the Scout rocket body that launched it.

Solidaridad 1 (Image: Gunter’s Space Page)

When Mexico retired its first telecommunications satellites – Morelos 1 and 2 – they turned to their creators at Hughes Space and Communications Company to create replacements. The first replacement was Solidaridad 1, launched along with Meteosat 6 by Ariane rocket from Kourou, French Guiana on 20 November 1993.

Also known as Satmex 3, Solidaridad 1′s name was chosen to indicate its role of uniting metropolitan and rural Mexico with the world. The satellite covered Mexico, with some bands extending to the United States, Caribbean and South America, providing “voice telephony, data communications, television relay, facsimile transmission, business networks … educational TV broadcasts … [and] nationwide mobile services.”

Twelve thousand rural schools across the country received educational programming transmitted through Solidaridad 1, and some relied entirely on these broadcasts.

The satellite was a 1641 kilogram Hughes HS-601 model winged cube with a 21-meter Solar array wingspan providing 3300 watts of power. Antennas on two sides transmitted in the Ku band and C band and the Earthward side had a 26-element dipole array.

Solidaridad 1 was designed to have an operational lifespan of 14 years, but in 1999 suffered failure of its primary SCP (Satellite Control Processor). The secondary SCP was activated, but it too failed the following year.

On 27 August 2000, Satmex received alarms indicating that the backup SCP had failed. After making 65 attempts to re-establish contact, Hughes technicians recommended deactivation. Electrical energy had been drained as the stricken satellite’s Solar arrays had lost alignment with the Sun. Solidaridad 1 was switched off and declared a total loss. Fortunately, $250 million insurance could be applied to construction of a replacement.

This wasn’t the first failure of a HS-601 satellite – various other satellites had undergone failure of one or both SCPs through the growth of crystalline whiskers on tin-plated relays. Engineers switched from tin to nickel plating to solve the problem.

The loss of Solidaridad 1 wiped out a variety of communications services for over 100 clients, who needed to be relocated in the following days to other satellites in the Satmex fleet, as well as to other operators. Restoring educational television services to the 12,000 rural schools required manual reorientation of antennas toward new satellites, and classes missed during this period were rebroadcast.

Solidaridad 1 is still up there today – stuck in geostationary orbit as it could not be moved to a graveyard. The Ariane rocket body that launched it is also visible.

Boeing Solidaridad Fact Sheet

Solrad 8 (Image from Gunter’s Space Page)

The United States Navy has a natural interest in Solar radiation because of its impact on radio communications on Earth. During the 1950s, attempts were made to measure radiation from Solar flares using rockets, but it took the advent of the satellite age for the field to mature.

The SOLRAD (SOLar RADiation) satellite program began in 1960 and continued until 1976, making it one of the longest-running series of satellites devoted to a single research program.

Early SOLRAD satellites were launched with the then-classified GRAB (Galactic Radiation And Background) satellites, the United States’ first intelligence satellites, designed to intercept Soviet signals.

The first SOLRAD/GRAB mission was the first multiple-satellite launch. It determined that radio fade-outs were caused by Solar X-ray emissions, was the first orbital observatory and the first satellite to be commanded to shut off.

SOLRAD 8, also known as Explorer 30 or SE-A (Solar Explorer A), was fabricated by the NRL (Naval Research Laboratory) and launched at 4:48 UTC on 19 November 1965 from Wallops Island.

The satellite was part of the International Quiet Sun Year program, studying the Solar minimum, transmitting data back to Earth and the Spacecraft Tracking and Data Acquisition Network (STADAN).

Emblem of the Naval Research Laboratory.

A 56.7 kilogram satellite of the aluminium ball family, SOLRAD 8 consisted of two 24-inch hemispheres with a 3.5-inch band, fitted with six solar panels and 14 equatorial solar X-ray and ultraviolet photometers. A satellite of somewhat similar design is depicted on the emblem of the Naval Research Laboratory.

SOLRAD 8 was the first satellite to use a new series of millipound gas thrusters to hold itself with its spin axis perpendicular to the Sun. Rotating at 60 rpm, each of its photometers would view the sun with each revolution.

Unfortunately, the spin system didn’t work as planned, and the satellite gradually slowed to 4 rpm on 12 September 1966. A respin command from ground control succeeded but exhausted the ammonia gas supply for the thrusters, after which it slowed again to 10 rpm in August 1967. As the satellite slowed, data dropped off, ending on 5 November 1967.

For keen space archaeologists with telescopes, SOLRAD 8 is still in orbit, along with the Scout rocket body that launched it and some associated debris. Another piece of debris decayed in 2009.

See also: SOLRAD 8 entry at National Space Science Data Center SSDC.

In 1959, Giuseppe Cocconi and Philip Morrison proposed what would become the mainstream strategy of the modern search for extraterrestrial intelligence: scanning for interstellar radio signals intentionally beamed towards the Solar system by advanced civilisations.

Ronald Bracewell of Stanford University, however, questioned some of the assumptions on which the nascent SETI program was founded:

• that interstellar communication was only practical using electromagnetic waves;
• that civilisations would transmit ‘on spec’ over geological timespans; and
• that a civilisation would be close enough that we would be among its targets.

In late May, 1960, Nature published his response, ‘Communications from Superior Galactic Communities‘ (paywalled). In it, he suggested that a civilisation might ‘spray some number of suitable stars, say, one thousand, with modest probes … armoured against meteorites and radiation damage, and stellar powered.’

These would take up an orbit within a stellar habitable zone and either attempt to gain the attention of indigenous sophonts or listen for their transmissions and report back (a response might already be on the way, he suggests!). The latter is the premise for Arthur C. Clarke’s short story ‘The Sentinel’, which inspired 2001: A Space Odyssey.

The advantage of this method of contact are that a local signal could be stronger than one attenuated by interstellar distance and that the plan does not rely on the emerging species to correctly guess the location and wavelength to search (a probe could listen for our signals and transmit back on the same).

Bracewell proposes that astronomers look for signs of probes within the Solar System – the first call to search for extraterrestrial artefacts since the collapse of the martian canal hypothesis – or be alert to the possibility that unexpected signals may be interstellar communications.

Maintaining a belief in the ‘Galactic Club’ vision, he expected that we would only find a single probe from our nearest neighbour, as the superior communities of the galaxy would act in concert to avoid duplication of effort. This Galactic Club (the term would be coined later by Bracewell, but fits here) would have long experience in contacting emerging communities.

This probe might even contain an ‘elaborate store of information and a complex computer’ so that it could converse with us – saving communication time.

Bracewell concludes with some discussion of the frequency and lifespan of superior communities. If we search and do not find a probe, perhaps the nearest superior community is beyond the range where successful communication is likely. Perhaps the mortality rate for civilizations is high.

Even so, some may achieve durability or quasi-permanence, he argues, and be searching for ‘rudimentary societies’ before they ‘burn out’:

They might already have satisfied their curiosity by archaeological inspection made at leisure on sites nearer home. On the other hand, the prospect of catching a technology near its peak might be a strong incentive for them to reach us.

On 19 September 1959, the modern search for extraterrestrial intelligence was born with the publication in the prestigious journal Nature of an article by Giuseppe Cocconi and Philip Morrison of Cornell University. The piece, ‘Searching for interstellar communications,’ proposed a search of nearby sun-like stars for microwave radio signals on the 21-centimeter hydrogen line.

You can read the article online at the (paywalled) Nature archive, or for free here and here. It’s quite short, go read!

Welcome back! For such a brief article, there’s a lot to think about.

First of all, it’s remarkable to see the seeds of the Drake equation in the first paragraph. The factors of planet formation, origin of life, and the evolution and lifespan of technological civilisations are all mentioned, and it will only take a little unpacking by Frank Drake in 1961 to produce his famous formalism.

The second paragraph is interesting too – assuming that advanced technological civilisations will actively signal to stellar systems where they expect intelligence to emerge. It’s never said explicitly, but the surely the implication is that we ourselves should take on the role not just of responder but of signaller to potentially inhabited worlds?

Leaving aside that implication, we can see that Cocconi and Morrison envision a benign ‘community of intelligence,’ looking forward patiently to our call. Ronald Bracewell will, in 1975, dub this vision the ‘Galactic Club.’ Picture civilisations of geological age sharing scientific knowledge among themselves and waiting to greet new species as they emerge.

There seems to be no consideration by the authors of space travel. The only practical method of communicating over interstellar distances, they say, is electromagnetic.

The authors explain their reasoning that the 21-cm hydrogen line is the optimum place to conduct a search, make some speculations about the nature of the signal, and suggest some targets in the Solar neighbourhood. SETI in the electromagnetic spectrum has remained the mainstream of the program to this day.

They close with the immortal line: ‘The probability of success is difficult to estimate; but if we never search the chance of success is zero.’

The following year, in 1960, Frank Drake followed Cocconi and Morrison’s proposal in conducting the first search for extraterrestrial signals – Project Ozma – from the National Radio Astronomy Observatory at Green Bank, West Virginia.

1960 also saw the publication of two works inspired by Cocconi and Morrison’s seminal article. These would themselves spawn new fields of inquiry, or subfields: Ronald Bracewell’s May 1960 paper on probes and Freeman Dyson’s June 1960 paper on what would become known as Dyson spheres.

The early emergence of the search for circumsolar and interstellar extraterrestrial artefacts – so soon after the birth of SETI itself – is satisfying for those who defend what has been a fringe of the mainstream search program.