Did you know that celestial objects and astrophysical phenomena emitted in the universe are studied from Piedecuesta?
In the heart of the Guatiguará Technology Park (PTG) of the Industrial University of Santander (UIS), the consolidation of Colombia’s first radio astronomy observatory is progressing, a milestone for national science. The project, led by the Electronic Control Modeling and Simulation Research Group (CEMOS), was designed and created by Julián Rodríguez Ferreira, professor and researcher at the UIS and doctor of physics, in conjunction with Elián Calderón Quintero, electronic engineer and student in the Master’s in Telecommunications Engineering program, and David González, also a student at this institution.
Although there are still details to be defined and adapted, the facility is already operating normally. According to Rodríguez Ferreira, the main objective is to develop the first area of radio astronomy in Colombia, while at the same time developing the infrastructure with UIS talent.
The CEMOS group, created in 2001, owes its name to the areas that guide its work: Control, Electronics, Modeling, and Simulation. It is currently developing six lines of research: expert supervision, automation, and control; prototype development; bioengineering and biomedical engineering; digital signal and image processing; optimization and modeling; and the application of microwaves to physicochemical processes. The group is affiliated with the School of Electrical, Electronic, and Telecommunications Engineering at the UIS.
Radio astronomy is the branch of astronomy that studies celestial objects and astrophysical phenomena by measuring their electromagnetic radiation emissions. Radio waves from the universe are picked up by radio telescopes (wave receivers and antennas) which, unlike optical telescopes, cannot record images, but rather measure the intensity of the radio waves received, usually in the form of an electrical signal at the receiver’s output or, in the simplest case, in the form of an audio signal provided by a loudspeaker.
“Radio astronomy is one of those ears we have for observing the universe because they are radio waves, so we always associate them with sound. The signal is received through antennas and generates an electrical signal from the universe that is proportional to what it receives,” he says.
The observatory has a radio interferometer, a system of several antennas that, although separated, electronically combine their signals to generate an image with the same resolution as a radio telescope the size of the distance between them.
According to Elián Calderón Quintero, an electronic engineer at UIS and a master’s student in telecommunications engineering, the radio interferometer is the cornerstone of this radio observatory.
In addition, Calderón Quintero explains, this site has “a weather station that measures environmental variables such as temperature, humidity, and radio interference. This allows us to determine the different types of interference we will have in the signal, especially for the low-frequency antenna.”
Large, strategic antennas
Although radio astronomy allows us to capture the frequency of the universe, since radiation passes through clouds, Professor Rodríguez Ferreira says that in order to capture these electrical signals, it must be done in open areas, preferably with as few clouds as possible and with large antennas; this allows us to capture the various frequencies emitted by the universe.
“The project began to take shape in 2016. First, we looked for people with training and interest in astronomy. We also sought students who were interested in this subject and who would strengthen their training in the area. Over the years, we have developed the radio infrastructure, and all the equipment and systems have been physically built here, because this technology was developed in Colombia by Colombians. That is a very important thing to highlight, and along the way we have been learning and training people,” says Rod.
The radio observatory is part of the Colombian Antarctic Radio Astronomy Program (PRAC). It is located at the PTG and operates 24 hours a day, 7 days a week, regardless of weather conditions. It has two antennas, each 25 centimeters in diameter. Its location must be strategic.
According to Calderón Quintero, the shelter, which is the instrument that performs the measurement, data collection, and transmission, has a radio link that allows direct communication via the internet so that everything can be monitored remotely.
“In addition, we monitor and control the antennas, which have two axes of movement: azimuth and elevation. This allows us to always point the antennas where we want to observe. Currently, they are tracking the sun, so every time the sun moves, the antennas will follow it and collect data,” says Calderón Quintero.
In 2017, the project received funding from the National Spectrum Agency (ANE) and is currently funded by the Ministry of Science, Technology, and Innovation.
The radio interferometer is in its initial phase and system calibration stage. It will be an instrument that will measure and validate in the field, making direct astronomical observations of stars and galaxies, among other things.
Sighting in the moorland
With the aim of expanding the detection of radio waves from celestial objects, the team of researchers took a radio telescope to areas near the Santurbán Moorland. This location was chosen thanks to its geographical conditions and the quality of its sky, which offer an ideal environment for capturing radio signals.
“In the Santurbán moorland, we believe that, due to its geographical conditions and the quality of the sky for radio signals, there are some very interesting places where we want to install our radio observatory,” says Professor Julián.
Although some sightings have already been recorded in this area of Santander, the researchers will not install an antenna here for the time being. Instead, work continues at the Guatiguará Technology Park to calibrate the instruments, with the aim of consolidating the University’s first professional radio astronomy observatory in Colombia, driven by UIS talent.
Sounds from the South Pole
But their project has already crossed borders. Professor Julián and Elián managed to install a low-frequency radio astronomy antenna in Antarctica during Colombia’s eleventh Antarctic Expedition.
They are the first Colombian scientists to develop Colombia’s first observational astronomy project in this location. To do this, they installed a radio telescope at the Glaciar Unión Polar Scientific Station, under climatic conditions similar to those at the South Pole, to study signals close to the origin of the universe from that location.
“We developed our radio telescope and left it operating there for over a year. In Colombia, very few researchers have achieved this level; three or four projects have succeeded, but ours is the one that has lasted the longest. That is a milestone,” says Rodríguez Ferreira.
Making and installing this antenna was no easy task. Rodríguez Ferreira says it was an odyssey. On the one hand, carrying the suitcase with the antenna and, on the other, getting it to work due to the extreme weather conditions.
“Everything is 1000 times more difficult. It’s just walking to the place, going to the site to install it. I mean, just walking 100 meters is a feat. So, we have to go on expeditions to leave the parts behind. The equipment was left there for a couple of nights and days, then we went back to retrieve it and look at the data,” explains the UIS professor and researcher.
After three attempts in three different missions, the calculations paid off, and they obtained the mathematical measurement that allowed them to determine the resistance of the ice in the polar ice cap.
There is little information about these measurements on the white continent. The latest reports found date back to the 1970s and 1980s, which means that this will be a contribution to the scientific community and all areas, because this is not only for astronomy; this value is useful to glaciologists and other areas of knowledge.
The installation of this antenna was a strategic move, explains Calderón Quintero, due to the low level of RFI contamination. “In this location, the level of interference with respect to Bucaramanga is a thousand times lower. This is a strategic location for the radio telescope. It gives us the potential to leave the instrument in place continuously and monitor it remotely from anywhere in the world.”
