Map of current distribution of Callisto instruments in October 2018. Update rate ~15 minutes, press reload to see latest status. One dot can represent up to 5 instruments.
Statistics: more than 150 instruments at more than 90 locations worldwide.Callisto stands for: Compound Astronomical Low cost Low frequency Instrument for Spectroscopy and Transportable Observatory
Type II burst (Ooty)
The CALLISTO spectrometer is a programmable heterodyne
receiver designed 2006 in the framework of IHY2007 and ISWI by
Christian Monstein (PI) as member of the former Radio Astronomy Group
(RAG) at ETH Zurich, Switzerland. The main applications are
observation of solar radio bursts and rfi-monitoring for astronomical
science, education and outreach. The instrument natively operates
45 and 870 MHz using a modern,
commercially available broadband cable-TV tuner CD1316 having a
frequency resolution of 62.5 KHz. The data obtained from CALLISTO are
FIT-files with up to 400 frequencies per sweep. The data are
transferred via a RS-232 cable to a computer and saved locally. Time
resolution is 0.25 sec at 200 channels per spectrum
pixels per second). The integration time is 1 msec and the radiometric
is about 300 KHz. The overall dynamic range is larger than
For convenient data handling several IDL-, PERL- and Python-routines
Many CALLISTO instruments have already been deployed, including: 10 spectrometers in India (2 in Ooty, 1 in Gauribidanur, 1 in Pune, 1 in Ahmedabad, 1 in Sangli, 2 in Bagalore, 1 in Nashik and 1 in Udaipur), one in Badary near Irkutsk, Russian Federation, two in Daejeon/South Korea, three in Australia (Adelaide, Melbourne and Heathcote), two in Hawaii, two in Mexico, one in Costa Rica, two in San Jose dos Campos/Brazil, three in Mauritius, 5 in Birr/Ireland, one in Ondrejov/Czech Republic, two in Ulaan Baatar/Mongolia, one in Germany (Essen), two in Anchorage/Alaska, two in Almaty/Kazakhstan, one in Cairo/Egypt, one in Nairobi/Kenya, one in Sri Lanka, four in Italy (3 in Trieste and 1 in Turin), two in Slovakia (Hurbanovo and Rotztoky), two in Humain/Belgium, 4 in Metsähovi/Finland, 8 in Switzerland (5 in Bleien, 1 in Zurich, 2 in Freienbach), 4 in Spain, 5 in Malaysia, 3 in Indonesia (Sumedong, Tomohon and Biak), one in Glasgow/Scotland/UK, one in Peru, one in Kigali/Rwanda, one in Pakistan, 2 in Denmark, one in Japan, one in South Africa, two in Kangerlussuaq/Greenland, 6 in Austria, one in Montevideo/Uruguay, two in Norway, one in Nepal and two in Ethiopia (Addis Ababa and Mekelle). Through the IHY/UNBSSI and ISWI instrument deployment program, CALLISTO is able to continuously observe the solar radio spectrum for 24h per day through all the year. All Callisto spectrometers together form the e-Callisto network. Callisto in addition is dedicated to perform radio-monitoring within its frequency range with 13'200 channels per spectrum. The frequency range can be expanded to any range by switching-in a heterodyne up- or a down-converter.
Instrument deployment including education and training of observers was financially supported by SNF, SSAA, NASA, Institute for Astronomy and ETH Global, formerly known as North-South Center of ETH Zurich and a few private sponsors.
Data access is free for everybody but we would appreciate credit to the Institute for Data Science FHNW Brugg/Windisch, Switzerland.
In case Callisto data are used for any publications, the instrument PI expects to be invited to be a co-author of the paper.
For this purpose, the paper must be sent to the PI at least two weeks prior to submission, so that he can review it,
possibly give comments, and decide whether he chooses to be a co-author.
Note that the explicit confirmation from the PI is needed for him to appear as a co-author on any such publication.
Adress for co-authorship: Christian Monstein, Radio Engineering, Wiesenstrasse 13, CH-8807 Freienbach, Switzerland.
RFI-map, derived from FIT-files. Color is proportional to the skewness of a 2-dimensional FIT-file. Data present the 200 best channels out of 13'200 possible channels of the frequency range of Callisto. This plot is kind of optimistic case in terms of rfi.
Skewness, derived from FIT-files which is a selection of the best 200 channels out of 13'200 possible channels.
RFI-map, derived from spectral overview. Color is proportional to (mean-rfi - quiet Sun flux), so it's a measure for minimum antenna gain to observe quiet Sun at current rfi-level. Spectral overview takes into account all possible 13'200 channels in the whole spectrum of Callisto.
Y-axis shows the average minimum antenna gain which is required to observe the quiet Sun at local mean level of rfi.