Wednesday’s Word: What is the Space Launch System (SLS)?

Today we’re introducing a new type of post on This Orbital Life: Wednesday’s Word.  The space world has lots of technical jargon and weird acronyms.  So, in order to help you sort it all out, every Wednesday we will take one phrase or word or acronym and break it down.  Ready? Let’s go!

This week’s word is actually an acronym: SLS.

SLS = Space Launch System

The Space Launch System is America’s next big rocket.  We had Apollo, we had the Shuttle and soon we’ll have SLS.  And when I say big, I mean really big.  It will be the most powerful rocket ever built, able to launch 143 tons to orbit.  That’s more than five times what the massive Shuttle could haul.

SLS is big.
SLS (on the right) compared to other famous rockets. Payload is in metric tons.


It’s strength isn’t the only thing big about it: it’s price tag is also quite large.  It will cost at least $500 million every time you send an SLS up, but more likely closer to $2 billion.  For comparison, SpaceX’s new mega-rocket is estimated to cost a measly $90 million to launch 58 tons to orbit.

Cost is not the only controversial thing about the SLS.  Basically, NASA doesn’t know what it will use the SLS for.  I’m not kidding.  It’s being told by Congress to build this thing.  That’s why it is sometimes derided as the “Senate Launch System.”  NASA talks about using this rocket to go to Mars but it currently has no funding to do so.  So, the first launch will be in 2018 with plans for a follow-on launch…seven years later.  Two launches in seven years makes a lot of people ask if it’s worth building such a beast, absent any strong reason (and funding) to use it.

So now you know: SLS is the Space Launch System.  A really powerful, really expensive rocket that could probably take us to Mars if we had the funding to do so.

What do you think about all this?