Copyrights and Use
The solar radio brightness maps by Metsähovi Radio Observatory (MRO) are licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
The images are provided for quicklook / browsing purposes only.
If you are interested in obtaining and using MRO data in research or publications, contact sun-metsahovi@aalto.fi
Also, if you use the images outside this website, we request that you inform us via email with a brief description of your project so that we may keep track of the impact of our work.
14-m radio telescope (37 GHz)
The RT-14 at MRO is a radome-enclosed Cassegrain-type antenna with a diameter of 13.7 m. The antenna is used for solar mapping, partial solar mapping, and tracking of any selected areas on the solar disk. The beam size of the telescope is 2.4 arc min at 8 mm (37 GHz). The noise temperature of the 8 mm receiver is approximately 280 K. The temporal resolution during observations is 0.1 s or less. The observations are comparable over the years. QSL is the median temperature of the data samples from the solar disk in the radio maps. The time span between two consecutive solar radio maps is around 120 s at the fastest.
Additional information
Public gallery at:
https://www.metsahovi.fi/solar-gallery
Documentation:
MRO-14, solar radio maps - technical overview:
Kallunki, J., Tornikoski, M., Tammi, J., et al. 2018, Astronomische Nachrichten, 339, 204
Kallunki, J., Lavonen, N., Järvelä, E., & Uunila, M. 2012, Baltic Astronomy, 21, 255
J.Kallunki: Studies of Solar Activity with Emphasis on Quasi-Periodic Oscillations (University of Turku, 2013):
http://www.utupub.fi/handle/10024/91948
MRO-14, solar radio maps - Quiet Sun calibration:
Kallunki, J., & Tornikoski, M. 2018, solphys, 293, 156
Copyrights and Use
The daily 11.2 GHz total radiation intensity curves by Metsähovi Radio Observatory (MRO) are licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
The images are provided for quicklook / browsing purposes only.
If you are interested in obtaining and using MRO data in research or publications, contact sun-metsahovi@aalto.fi
Also, if you use the images outside this website, we request that you inform us via email with a brief description of your project so that we may keep track of the impact of our work.
1.8-m radio telescope (11.2 GHz)
1.8-m radio telescope has measured the total radiation of the Sun since January 2001, at a wavelength of 2.7 cm. The telescope has a beam size of 81.6 arc min, and its system noise temperature is approximately 270 K. The radio telescope has no protective radome; therefore, it is vulnerable to prevailing weather conditions. The spikes in the plot indicate solar radio bursts, except the spikes at UTC 9:00 or 10:00, which are the daily, purposely injected, calibration signal. High sampling rate (1 kHz) enables studying fine structure of flares, including short periodic oscillation phenomena.
Additional information
Daily plots:
https://www.metsahovi.fi/sun/plots/sundaq-lin/
Documentation:
Technical overview:
Uunila, M., & Kallunki, J. 2015, apss, 359, 33
Voltage to Solar Flux Unit (SFU) conversion:
https://www.metsahovi.fi/Sunant/README.txt
Copyrights and Use
The solar spectrographs based on measurements at Metsähovi Radio Observatory (MRO) are provided by Bleien Solar Radio Data service.
The images are provided for quicklook / browsing purposes only.
If you are interested in obtaining and using MRO data in research or publications, contact sun-metsahovi@aalto.fi
Also, if you use the images outside this website, we request that you inform us via email with a brief description of your project so that we may keep track of the impact of our work.
Callisto - dynamic solar radio spectra
e-Callisto is International Network of Solar Radio Spectrometers. Four Callisto spectrometers are operating in Metsähovi Radio Observatory.
The frequency resolution of the spectrometer is 62.5 kHz. The data obtained from CALLISTO are FITS-files up to 400 frequencies per sweep. Time resolution is 0.25 sec at 200 channels per spectrum (800 spectral pixels per second).
Two of these spectrometers are observing solar dynamic spectra at frequency range between 45 and 850 MHz (vertical, Callisto #59, and horizontal, Callisto #60, polarizations).
The receiving antenna is commercial logarithmic periodic antenna. Other two Callistos are attached to Low-Frequency Antenna. The antenna has two different polarization outputs (East-West, Callisto #61, and North-South, Callisto #62) and its frequency range is between 16 and 90 MHz (previously 5 and 120 MHz). This instrumentation is dubbed the Metsähovi Solar Observing Low-Frequency Antenna, or METSOLA. Callisto observing frequencies are very sensitive for radio frequency interferences (RFI).
Additional information
Documentation:
Callisto technical overview:
Kallunki, J., Uunila, M., & Monstein, C. 2013, IEEE Aerospace Electronic Systems Magazine, 28, 5
Copyrights and Use
The pyrheliometer intensity curves by Metsähovi Radio Observatory (MRO) are licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
The images are provided for quicklook / browsing purposes only. If you are interested in obtaining and using MRO data in research or publications, contact sun-metsahovi@aalto.fi
Also, if you use the images outside this website, we request that you inform us via email with a brief description of your project so that we may keep track of the impact of our work.
Pyrheliometer
Pyrheliometer measures solar ultraviolet (UV) radiation at spectral range of 200 to 4000 nm. The observations are very sensible to the prevailing atmospheric conditions (=weather). Thick clouds and rain will block the UV detection. Pyrheliometer is attached to the down rim of a microwave telescope dish that observes the total solar radio flux at 11.2 GHz.
Additional information
Daily plots:
https://www.metsahovi.fi/sun/plots/pyrheliometer/
Other sources
- NOAA Solar and Geophysical Event Reports
- Solar Monitor
- Helio viewer
- SILSO
Solar activity: