A Russian cosmonaut on board the International Space Station has broken the record for total time in space by spending more than two years in orbit during his career.

At 1.42am Moscow time on Monday, Gennady Padalka, the commander of the current space station mission, broke his countryman Sergei Krikalev’s record of 803 days, nine hours and 41 minutes.

Padalka is due to return to earth on 11 September, by which time he will have spent 878 days in space – almost two and a half years. On 21 June he celebrated his 57th birthday in orbit.

The commander said at a press conference before his flight in March that he would like to try for 1,000 days in space after his current record-breaking mission is over.

Padalka’s fifth trip into space has not been without challenges. An unmanned Dragon rocket owned by the US company SpaceX exploded shortly after liftoff on Sunday on a mission to resupply the space station with two tons of food and equipment.

Nasa has said the space station has enough reserves to continue operating for several months, and the Russian Space Agency has made similar statements. A Russian Progress M-28M rocket will launch on 3 July with supplies.

Cosmonaut Yury Baturin, who travelled to the Mir space station with Padalka on board Soyuz TM-28 in 1998, said that as “one of the cosmonauts most experienced in dangerous situations”, Padalka was well-equipped to deal with any challenge. Baturin has been corresponding with his former commander and congratulated him by email on Monday.

Padalka took off for the space station on 27 March from the Baikonur Cosmodrome in Kazakhstan with fellow Russian Mikhail Kornienko and American Scott Kelly. Kelly and Kornienko will remain on the space station for a year to study the effects of long-term spaceflight on the human body, a key factor in the quest to reach Mars.

Extended stays in space are hard on the human body, since in conditions of microgravity the spine stretches out, muscles tend to atrophy and bone density can decrease, among other problems. Lengthy space missions also present psychological challenges, Baturin said.

“It’s not so much the hardships of working with other crew members, but rather that you’re cut off from your family, from your home, and for a very long time,” he said.

“Gennady is a real professional. He loves his work, and when a person loves his work, time doesn’t drag on. He deals with [psychological challenges] through his work.”

Krikalev and the director of the mission control centre told the state news agency Tass that they would congratulate Padalka, although the agency noted that the commander would not officially set a new record until he has spent at least 5% more time in space than the previous record holder, which will happen in early August.

Russia’s space industry received a boost last week when its space agency signed the largest contract in the history of commercial space flight. In a deal estimated at $1bn-2bn (£630m-£1.26bn) with the French space launch provider Arianespace, the agency’s rockets will deliver between 650 and 720 microsatellites built by the British company OneWeb into orbit, facilitating internet service in remote corners of the globe.

Russia’s space and defence tsar, Dmitry Rogozin, tweeted on Monday, with a link to an article about the SpaceX explosion: “It’s a great time for our US colleagues to think about the logic of their sanctions against the Russian Space Agency. There’s no room for politicking in space.” The two countries restricted their space cooperation in tit-for-tat measures after US sanctions were adopted against Russia last year, although they continue to cooperate on the International Space Station.