'Extremely' is the answer. Being hit by a 'sugar-cube' of space debris is the equivalent of standing next to an exploding hand-grenade. And the problem is only getting worse.
"This week, the International Space Station (ISS) made its latest move in a long-running game of cat and mouse with pieces of space debris. For years now, the ISS has been dodging collisions. Some of the latest manoeuvres took place in April 2011 and January 2012. What may not be so obvious is that many of its "near-misses" are due to fragments from a single event in 2009 that shocked the aerospace community. ..."
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