D V ARaghava Murthy, who retired last month as the head of earth observation systems, Isro, said the engineering model of SB Sat was undergoing tests and is ready for clearance of the flight model. "The launch is slotted for April or May. Students have to deliver the flight model," said Raghava Murthy during a lecture on small satellite and satellite technology at a conference at the university on Thursday.

"During the tests, transmitters and receivers were working well in minus temperature, which is critical for radio frequency," he said. SB Sat, which weighs less than 2kg, will carry sensors that will gather data to study greenhouse gases which are major pollutants warming the earth.

"The satellite will come in contact with the ground station in the University only for 10 to 15 minutes a day. It is sufficient for us to gather the needed data," said Vasanth, a faculty member of Sathyabama University involved in the project. While data will be given to Isro for interpretation, Vasanth said that idea was to develop a pollution model for the country. The lifetime of the satellite is expected to be between six months and one year.

SB Sat project was initiated in 2009. Isro and Sathyabama University signed an MoU to support the design, development and launch of the satellite. Subsequently, a Space Technology Centre was established to conduct advanced research in rocketry, satellites and space applications on the university campus. A team of 15 students and six faculty members have been working on the project periodically reviewed by Isro scientists. Students were selected by Isro after a screening process that included a written test and interview.

Isro earlier launched two satellites designed and developed by students in the city. A 40kg Anusat by students of Anna University and a 10kg SRM Sat by SRM University students were launched in 2009 and 2011 respectively.

"Isro has helped universities to make these satellites so that students can have hands-on experience," Raghava Murthy said.