Rockets blow up.

New Shepard spacecraft blows up. Try again.

I don’t want to sound too cavalier about this, but the fact is: rockets blow up. They are filled with explosive fuel which is then ignited. Trouble, sometimes, is inevitable.

This isn’t to downplay the serious implications of an exploding rocket. Some rocket failures are more serious than others: the Challenger failure, with the loss of seven lives, was crushing.

But sometimes rocket failures are not that serious; they are expensive and a part of learning to build new, better, and successful space vehicles. Thinking about rocket failures in recent years—and in recent weeks—illustrates the point

Remember the Ares I-x? An early experimental version of what was to become the Ares series of launchers flew successfully in October 2009. (There was some damage and other irregularities; but uncovering and fixing these irregularities is the purpose of early flights of new rocket designs.) But Ares was cancelled, because engineers hadn’t yet solved all its technical issues and the costs were deemed too high. I find it amazing that after more than 50 years of spaceflight, anyone imagines that new spacecraft won’t have difficulties or require significant budgets. Innovation requires taking chances and often spending more money.

Anyhow, the NASA rocket was deemed a failure. And people praised the private space companies. Now, I love private space companies almost as much as I love NASA—but nature will not be fooled. Private scientists and engineers face the same challenges as government ones. Orbital Sciences, a private company with a long history of successful launches, has been struggling with its Taurus XL launcher—with $424 million satellite launch failure back in March. They had an earlier failure, which destroyed Orbiting Carbon Laboratory in 2009. But Orbital Sciences move ahead, now readying a test flight of their system to re-supply the ISS. And they should.

Jeff Bezos’ somewhat mysterious space company, Blue Origin, has a high-profile failure this week. His “New Shepard” spacecraft crashed and was destroyed during a test. It’s dramatic; it’s disheartening; it’s expensive. But it happens. Nobody was killed. Live and learn.

SpaceX, which has had some great success with the Falcon/Dragon combo, has had multiple failures. People seem to forget this now that SpaceX is on a role. (Yeah, I’m a fan, too…but I also don’t expect perfection.)

Even the venerable Soyuz failed in its most recent mission to send supplies to the ISS. This is the vehicle which has carries cosmonauts into space without a single fatal accident since 1971. It happens. If you demand complete safety and success, rocket science isn’t for you.