MOSCOW (AP) _ Tests show a leaky hatchway on the Russian space station has been repaired and pressure partly restored in the facility's docking chamber, ground control officials said today.

Cosmonauts had failed to properly seal the hatch separating outer space from the docking chamber when they returned from a spacewalk on Nov 3. The chamber is closed off from the rest of the station, so the resulting loss of pressure in the docking chamber did not affect other parts of the Mir, which has been plagued by mishaps for much of the year.

When Anatoly Solovyov and Pavel Vinogradov again headed out into space on Thursday, they found a white powder-like residue on the edge of the hatch. On their return, they removed the substance and installed additional clamps to make sure the seal on the hatch was airtight.

Regular checks since then show the hatch has stopped leaking, said Vera Medvedkova, a Mission Control spokeswoman.

``Ground controllers believe the white residue could be ice crystals, but no final conclusion on its nature has been made,'' she said.

Solovyov, Vinogradov and U.S. astronaut David Wolf were doing routine maintenance and scientific experiments today, taking advantage of the increased power supply after last week's repairs, Medvedkova said.

During Thursday's spacewalk, the cosmonauts installed a new solar panel, nearly restoring Mir's power supply to where it was before a June 25 collision with a cargo ship.

Eight of Mir's 10 solar panels are now working normally, the ninth is operating at less than full capacity and one was damaged beyond repair in the crash.

The accident knocked out four solar panels, cutting the Mir's power supply almost by half.

Mission Control said the next spacewalk is set for Dec. 5, when Solovyov and Wolf are to work on scientific experiments on Mir's hull. Later in December, Solovyov and Vinogradov are expected to make one or two more trips outside the station to try to patch up holes in the Spektr module, which was pierced in the collision.