NASA's Phoenix Mars lander has hit a glitch in its first attempt to sample Martian soil - the Red Planet's surface may have proved too "clumpy" for one oven in the Thermal and Evolved-Gas Analyzer (TEGA).

Phoenix recently scooped up a cup-sized sample of material for the "high-temperature furnace and mass spectrometer" TEGA, which features screened openings so that only particles less than 1mm can pass into the device's miniature ovens. Once inside, they're slowly heated up during a week's analysis to determine the soil's water and mineral content.

That's the plan, but an infrared beam which is supposed to confirm particles have entered the first oven hasn't as yet detected any, and according to NASA, scientists "suspect the soil may be clumped together too tightly".

Accordingly, engineers are mulling just how to encourage some of the clogged sample into the oven using "mechanical shakers". Spokeswoman Sara Hammond said they "may send instructions to vibrate the compartment after they inspect the problem for a day or two".

If NASA fails to coax the reluctant Martian soil into the clogged TEGA oven it may well go unused, Hammond said. However, since the TEGA has a total of eight ovens, that would not necessarily mean an end to the mass spectrometer part of the mission. ®

Related stories

• Phoenix sees snow above Mars, but it's not sticking (30 September 2008)
• Mars Lander shows rock who's boss (24 September 2008)
• NASA to sniff Martian atmosphere (16 September 2008)
• NASA: Mars is good habitat for Terry Pratchett dragons (6 August 2008)
• Phoenix spies probable Martian water ice (23 June 2008)
• Phoenix eats dirt (12 June 2008)
• Phoenix prepares to flex its muscles (28 May 2008)
• Phoenix beams back Martian postcards (26 May 2008)