Bear Lake Observatory
 Utah State University
Center for Atmospheric and Space Science
Bear Lake Observatory

25.5 MHz Riometer
for studies of the ionospheric D Region

Riometers receive radio frequency energy, and then produce a voltage relative to the amount of energy received. The BLO (Bear Lake Observatory) Riometer specifically measures frequencies between 25.2 and 25.8 MHz. The BLO Riometer can produce anywhere from zero volts, meaning no energy is being received, to its maximum of 7.2 volts. Its antennae allow for coverage of the majority of the sky. For the most part, the energy received comes from astronomical radio sources like the star Cassiopeia A, Jupiter, the Milky Way center, and the sun, but there are also some terrestrial sources occasionally picked up by the riometer.
- Jennifer Albretsen, Undergraduate Research Fellow

The objective of the riometer is to allow us to analyze absorption of radio waves in the upper atmosphere (particularly the ionosphere). This subject is of interest because the level of absorption affects communications here on earth. If the absorption is low, communications will not be affected greatly but if absorption is high communication with radio waves can be virtually useless. While we know some of the reasons for fluctuations in absorption there are still many unknowns. Hopefully we can discover some of these unknowns by cross-referencing our riometer data with phenomena that may be affecting absorption in the ionosphere and thus discover reasons for the fluctuations.
- Robert Call, Undergraduate Research Fellow

For more information...

Please see Understanding Midlatitude Riometers for a discussion of the instrument and the data it produces.

Weekly summary reports are available in Adobe PDF files:
Daily plots in the summaries include the minimum, maximum, and median values for 30 second acquisition intervals. Solar x-ray flares of M- and X-class are indicated on the plot, as are Type II and Type IV solar radio bursts in the HF range. Due to frequent power outages, the hourly calibration pulses in the riometer data are not time-synchronized.

Data acquisition system
 Riometer and antenna
Data acquisition system
 Riometer and antenna in the field

[USU Physics Dept.] [Space Environment Corp.] [SEC BLO Data]