Indian navigation satellite stuck in transfer orbit after propulsion failure

WASHINGTON — A recently launched Indian navigation satellite is stranded in a transfer orbit after the failure of its onboard propulsion system and could soon renter.

The Indian Space Research Organisation (ISRO) stated Feb. 2 that the NVS-02 satellite, launched Jan. 28 (Eastern time), suffered a thruster failure that is keeping the spacecraft from raising its orbit as planned.

According to a statement posted on ISRO’s website but not otherwise publicized by the agency, “the orbit raising operations towards positioning the satellite to the designated orbital slot could not be carried out as the valves for admitting the oxidizer to fire the thrusters for orbit raising did not open.”

The spacecraft launched on a Geostationary Satellite Launch Vehicle (GSLV) Mark 2 rocket from the Satish Dhawan Space Centre. The launch was designed to place NVS-02 into a geostationary transfer orbit with a perigee of 170 kilometers and apogee of 36,577 kilometers.

Latest data from the Space Track catalog maintained by the U.S. military show that that satellite remains in a similar orbit, with a perigee of 165 kilometers and apogee of 37,582 kilometers.

ISRO noted in its statement that other systems on the spacecraft were working well, including a successful deployment of its solar panels. That statement, though, suggested that ISRO had given up on fixing the propulsion system on the satellite.

“The satellite systems are healthy and the satellite is currently in elliptical orbit. Alternate mission strategies for utilising the satellite for navigation in an elliptical orbit is being worked out,” ISRO stated.

However, the low perigee of NVS-02 would put the spacecraft in danger of reentering soon because of the high atmospheric drag at that low altitude. It was not clear if there are alternative propulsion systems on the spacecraft that could raise the perigee enough to avoid a reentry in the near term.

NVS-02 is based on ISRO’s I-2K satellite bus, which has been used for other Indian communications and navigation satellites operating in geostationary orbit. The spacecraft had a launch mass of 2,250 kilograms.

The spacecraft was intended to operate at 111.75 degrees east in GEO, replacing the IRNSS-1E spacecraft there. It is the second of five satellites planned for India’s Navigation with Indian Constellation, or NavIC, program to provide positioning, navigation and timing services in India and the surrounding region. The first, NVS-01, launched in 2023 and is in operation in GEO.