The European Space Agency says its Philae lander is doing well and has succeeded in planting a thermometer in the comet where it touched down this week.

The agency said Friday that scientists have received a steady stream of data from the lander, which on Wednesday became the first spacecraft to touch down on a comet. However, their job is complicated by the fact that Philae landed next to a cliff that is blocking sunlight from its solar panels.

Planting a thermometer in the surface was Philae's first so-called "mechanical operation" but ESA says it will hold off on any more for now. The lander's primary battery only has power for another day or so and scientists are contemplating realigning it so that the solar panels can charge the craft.