« The stars song » (Le Chant des étoiles ***)

« Le chant des étoiles » *** is a cultural and scientific project of experimental research in astrophysics (radioastronomy), hyper frequency radio communications by amateur radio stations of a non profit  association Dimension Parabole under contract with Etablissement Public du Parc et de la Grande Halle de la Villette, EPPGHV.

The purpose of the association is the rehabilitation of a radio-telescope that had been designed and installed in the Parc de La Villette when the Cité des Sciences et de l’Industrie was created in the 1985-1986’s in Paris 19. The radio-telescope instrument was part of a public demonstration project dedicated to astronomy initiated by Michel Charles. It was designed for the detection of radio signals coming from space and more specifically our Galaxy. However, to our knowledge, due to various issues, the radiotelescope had never been activated until now.

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Back in 2011 the Association des Radioamateurs de Paris (ARP75) contracted with EPPGHV for the recovery of the radiotelescope but could not achiev the project. The succeeding association « Dimension Parabole » has subscribed a new contract with EPPGHV in order to rehabilitate the instrument.

Project goals are multiple. The first one is to establish a cartography of our Galaxy by receiving and measuring signals emitted at the frequency of atomic hydrogen abondant in the universe. This was the original goal when the instrument had been designed for general public astronomy demonstrations.

Experimental radiocommunications on hyperfrequencies by radioamateurs may look strange to most people. Amateur radio stations use different means in order to achieve long distance trans horizon communications, such as artificial satellites or other natural objects.

For example they can use reflection of signals by the Moon, this is called « Earth-Moon-Earth » or « EME » commuications, or via meteorites or « meteor scatters » , via rain clouds « rain scatter », via aurora borealis, via troposphere sporadic layers, or via amateur satellites.

Secondly we intend to perform communications with other radioamateur stations by using the Moon to reflect radiosignals or relayed by a radio transponder module on board a geostationnary satellite. Recently an Amateur Radio satellite designed under the responsability of AMSAT-DL has been launched by a Space-X falcon rocket and put into geostationary orbit. It is located at 26°East. The satellite allows communications between amateur station using telegraphy, telephony anddigital television modes along a large Earth area. This will be our third activity.

We thus participate at our own level to personal and collective education, about diffusing scientific knowledge, international exchanges and mankind closer relationship, without any financial interest as specified in amateur radio regulations by the International Telecommunication Union (ITU).

« Le chant des étoiles » project will allow the demonstration of radio astronomy and amateur radio transmissions to general public. It can be used to help science student education and promote relationship throughout countries. Different events will be organized with didactic workshops and demonstrations.

Meanwhile however, as many years passed without maintenance, parabole mechanical parts have suffered. Rust on one motor reducer and gearings have broken pins when rotation test of the antenna was performed. Remember that no lubrification was done during more than thirty years !

Recently in 2018, Dimension Parabole association asked EPPGHV to provide new underground main power and Ethernet cables.  DP team awaked the preamplifier located nearby the dipole located at the primary focus of the antenna. This was done by injecting a DC voltage into coaxial cable connected to the dipole. The old coaxial cable was partially replaced by a new one. Another preamplifier adjusted to 1200-1400 MHz was finally put in front of an ordinary Software Defined Radio receiver.

Received signals captured by the above devices to our surprise already showed a radio image of our Galaxy after being analyzed locally on micro computers. Real time signals can be looked at via Dimension Parabole WebSDR. Read details about recently activated reception and first Galaxy map computed on last news dedicated menu.

Antenna declinaison motor to be repaired

Dimension Parabole is associated with Hackers from Electrolab (Nanterre) that offered to repare the telescope instrument antenna declination motor.

Folie N4 Radio Club station building close to the radiotelescope

Dimension Parabole is sharing with Internet radio broadcast station *DUUU  the use of one of the red buildings « Folie N4 » located nearby radiotelescope. Radioamateur and radioamateur by satellite stations are being installed in Folie N4 shared with *DUUU recording studio.

Please have a look at last news pages.

*** « Le Chant des étoiles » – A french composer, Louis Dandrel, created in 2000, Le Chant des étoiles, a music inspired by pulsars song, where waves captured by radiotelescopes are tranposed.