Loss of signal begins

The expected loss of signal from Mars Reconnaissance Orbiter has begun.

This is another critical juncture, as the thrusters continue to fire and there is no data coming back from the spacecraft. The blackout will last almost 40 minutes. We'll have to wait until about 5:16 p.m. to find out whether MRO made it.

That's the point in flight when NASA lost another of its Mars spacecraft. In the fall of 1999, the Mars Climate Orbiter went into the blackout period and NASA never reacquired the signal. The investigation that followed that mishap determined that a mistake in the navigation software (involving the use of English rather than metric units) led the spacecraft to dive too sharply toward the planet. Coming in too low, the spacecraft burned up rather than inserting itself into normal orbit.

So, now the controllers are left to wait out this high drama as Mars Reconnaissance Orbiter slips around the back side of the red planet. Going into the blackout, though, MRO's engines continued to burn nominally and all appeared well.