MOSCOW, July 25: Freed from major repair duties, the accident-prone crew of the Mir space station studied plants and sleep on Thursday and prepared for the return of two Russian cosmonauts to earth next month.

While American astronaut Michael Foale tended his cosmic greenhouse, his two Russian colleagues donned big pleated pants with vacuum pumps to restore normal blood circulation.

The vacuum costumes are to help the cosmonauts adjust to earth's gravity after the weightlessness of space, said Valery Lyndin, spokesman for Mission Control Center outside Moscow.

``The costumes look like large pleated pants from which air is gradually pumped out,'' he said.

Alexander Lazutkin, who continued an experiment linked to sleep study, and commander Vasily Tsibliyev are to return to earth on August 14, after a troubled six months aboard the orbiting station.

Foale comes down in September after the shuttle Atlantis swings by to pick him up.

Worst among Mir's calamities of recent months was a collision with a cargo ship last month that ruptured one of six modules and caused the station to lose half its power.

Russian space agency Director Yuri Koptev said on Thursday that 100 billion to 125 billion rubles ($ 17 million to $ 22 million) in damage was done when the cargo craft slammed into the Spektr scientific module and ricocheted off it several times ``like a billiard ball''.

He suggested the Government reduce its planned budget cuts to the space program, so the holes in the Spektr can be fixed without further dents to the Mir's battered funding.

Citing crew stress and Tsibliyev's irregular heartbeat, ground controllers have delayed crucial repairs to the 11-year-old station until a new pair of cosmonauts arrive.

But a medical consultant for the mission downplayed any health problems on Thursday. Viktor Baranov, first deputy director of the Institute of Medical and Biological Problems, described Foale's and Lazutkin's health as good and Tsibliyev's as satisfactory.

Most vital systems aboard the crippled station were functioning normally on Thursday, Mission Control said.

The new crew -- Anatoly Solovyov and Pavel Vinogradov -- blasts off on August 5 from the Baikonur launching site in Kazakstan and arrives on August 7.

The fresh team plans spacewalks inside and outside the station to restore power cables disconnected during the collision, and survey the two holes thought to have been caused by the crash.

Among other Mir mishaps since February were a fire, oxygen system breakdowns and a computer crash last week.

Copyright © 1997 Indian Express Newspapers (Bombay) Ltd.