Image received by astronomer Cees Bassa (@cgbassa) using the Dwingeloo Telescoop
Many thanks to SWLing Post contributor, Eric McFadden (WD8RIF) who shares the following story from The Planetary Society:
Earlier this week, on October 10, radio amateurs all around the world worked together to get the Chinese Longjiang-2 spacecraft to take an image of the Earth and the far side of the Moon. Radio commands were generated by MingChuan Wei in China, transmitted to the spacecraft by Reinhard Kuehn in Germany after which they were received by the spacecraft in lunar orbit. In turn, the spacecraft transmitted the image back to Earth, where it was picked up by radio amateurs in Germany, Latvia, North America and the Netherlands.
Since June this year, the Chinese Longjiang-2 (also known as DSLWP-B) microsatellite has been orbiting the Moon. The satellite is aimed at studying radio emissions from stars and galaxies at very long wavelength radio waves (wavelengths of 1 to 30 meters). These radio waves are otherwise blocked by the Earth’s atmosphere, while the lunar environment offers protection from Earth-based and human-made radio interference. Longjiang-2 was launched to the Moon together with an identical twin, Longjiang-1 (DSLWP-A), together acting as a radio interferometer to detect and study the very long wavelength radio waves by flying in formation in lunar orbit.
Besides the scientific instruments, both Longjiang satellites carry a VHF/UHF amateur radio transmitter and receiver (a transceiver) built and operated by the Harbin Institute of Technology (in Chinese). The Longjiang-2 transceiver also includes an onboard student camera, nicknamed the Inory Eye. The Harbin team built on experience gained with the Earth-orbiting LilacSat-1 and LilacSat-2 nanosatellites, which allow radio amateurs to receive satellite telemetry, relay messages and command and download images taken with an onboard camera.
While receiving signals from satellites in low Earth orbit requires only relatively simple antennas, doing so for satellites in orbit around the Moon (a thousand times more distant), is much harder. To this end Longjiang-1 and 2 transmit signals in two low data-rate, error-resistant, modes; one using digital modulation (GMSK) at 250 bits per second, while the other mode (JT4G) switches between four closely spaced frequencies to send 4.375 symbols per second. This latter mode was developed by Nobel-prize winning astrophysicist Joe Taylor and is designed for radio amateurs to relay messages at very low signal strengths, typically when bouncing them off the surface of the Moon.
[M]any radio amateurs have been able to receive transmissions from Longjiang-2. Usually, the transceiver is powered on for 2-hour sessions at a time, during which GMSK telemetry is transmitted in 16-second bursts every 5 minutes. After some testing sessions in early June, the JT4G mode was activated, with 50 second transmissions every 10 minutes.
Specialized open source software written by MingChuan Wei and the Harbin team enables radio amateurs to decode telemetry as well as image data and upload it to the Harbin website.
The JT4G mode has allowed radio amateurs with small yagi antennas to detect signals from Longjiang-2 (using custom software written by Daniel Estévez).[…]
Recently, I started posting Colin’s recordings on a schedule so that each recording is being published exactly 40 years from the original broadcast date. Check out the Shortwave Radio Audio Archive each day (or subscribe via iTunes) to listen to the recordings.
Below, I’ve embedded the recording from New Year’s Day 1978 where we learned that Yuri Romanenko and Georgi Grechko toasted the New Year with fruit juice (for obvious reasons, champagne was not allowed on the station!).
History changed on October 4, 1957, when the Soviet Union successfully launched Sputnik I. The world’s first artificial satellite was about the size of a beach ball (58 cm.or 22.8 inches in diameter), weighed only 83.6 kg. or 183.9 pounds, and took about 98 minutes to orbit the Earth on its elliptical path. That launch ushered in new political, military, technological, and scientific developments. While the Sputnik launch was a single event, it marked the start of the space age and the U.S.-U.S.S.R space race.
The story begins in 1952, when the International Council of Scientific Unions decided to establish July 1, 1957, to December 31, 1958, as the International Geophysical Year (IGY)because the scientists knew that the cycles of solar activity would be at a high point then. In October 1954, the council adopted a resolution calling for artificial satellites to be launched during the IGY to map the Earth’s surface.
In July 1955, the White House announced plans to launch an Earth-orbiting satellite for the IGY and solicited proposals from various Government research agencies to undertake development. In September 1955, the Naval Research Laboratory’s Vanguard proposal was chosen to represent the U.S. during the IGY.
The Sputnik launch changed everything. As a technical achievement, Sputnik caught the world’s attention and the American public off-guard. Its size was more impressive than Vanguard’s intended 3.5-pound payload. In addition, the public feared that the Soviets’ ability to launch satellites also translated into the capability to launch ballistic missiles that could carry nuclear weapons from Europe to the U.S. Then the Soviets struck again; on November 3, Sputnik II was launched, carrying a much heavier payload, including a dog named Laika.
Immediately after the Sputnik I launch in October, the U.S. Defense Department responded to the political furor by approving funding for another U.S. satellite project. As a simultaneous alternative to Vanguard, Wernher von Braun and his Army Redstone Arsenal team began work on the Explorer project.
On January 31, 1958, the tide changed, when the United States successfully launched Explorer I. This satellite carried a small scientific payload that eventually discovered the magnetic radiation belts around the Earth, named after principal investigator James Van Allen. The Explorer program continued as a successful ongoing series of lightweight, scientifically useful spacecraft.
The Sputnik launch also led directly to the creation of National Aeronautics and Space Administration (NASA). In July 1958, Congress passed the National Aeronautics and Space Act (commonly called the “Space Act”), which created NASA as of October 1, 1958 from the National Advisory Committee for Aeronautics (NACA) and other government agencies.
Yesterday, while listening to the BBC World Service, I heard this fascinating documentary focusing on the Voyager I and II spacecraft. It absolutely blows my mind that both of these spacecraft have been operating for 40 years and continue to send signals back to Earth. Talk about weak signal DX!
Voyager 1 and 2: Still operating after 40 years in the depths of space. Voyager 1 is currently some 20 billion kilometres from Earth travelling at 15.5 kilometres a second. It takes 19 hours for a signal from the spacecraft’s 20 watt transmitter to reach home. Voyager 2 is 17 billion kilometres away and will soon leave the Solar System.
Launched in 1977, the twin spacecrafts have explored the giant planets and their strange moons, investigated the boundary of the Solar System and changed how we see our place in the Universe. The probes even carry a message for aliens in the form of a golden record.
Retired NASA astronaut Ron Garan meets many of the original team still working on the mission, nursing the twin spacecraft through their final years.
Sean Gilbert, WRTH’s International Editor, recently shared this audio he originally recorded on June 19, 2014. Sean writes:
With all the interest in space and the ISS at the moment, I thought I would share a recording I made on 19 June 2014 @ 1715 UTC. This is from the Russian part of the ISS and the audio (which is in Russian) is of the cosmonauts talking during a spacewalk (EVA as they are known). The person speaking is actually in space, outside of the ISS. The audio begins about 2 mins into the recording and lasts for about 5 mins.
[…]This was received on 143.625MHz NFM (+/- a few kHz due to doppler shift). Receiver here was a Funcube Dongle Pro + into a 2 element circular polarised turnstile in the attic. Signal was lost at a distance of 2000km (to the East of my location in IO92ma) at 3 degree elevation. Altitude of ISS was 418km above earth.
The image [above] shows a grab of the signal, exhibiting doppler shift due to the ISS orbit in relation to the earth.
[…]I would be interested to know what they are saying. […]To me this was far more exciting than receiving SSTV pictures from the ISS. I may never hear another EVA – I am just thankful that I found this as it was an announced/schedules EVA.
That is very cool, indeed, Sean! At some point, I must make an effort to venture up to the VHF neighborhood and attempt to hear the ISS.
I hope there’s a Russophone reader out there who can help Sean interpret the EVA dialog! Please comment!
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