Starship SN8 ready to fly

 Over the last few weeks, SpaceX has been testing various prototypes of its Starship spaceship.  Today, it's assembled a working version ready for a hop test to 150 metres.  If that works, and they may do several hop tests to suss out all the problems, then they'll do a flight to 15 kms.  

(Picture from SPadre)

On its way down from the 15 km 'hop', the Starship will test out the 'skydiving' manoeuvre, using its flaps to slow itself down, before turning vertical (tail first) to land retro-propulsively.  This will be a key test, because SpaceX is relying on this technique to bleed off the very high velocities that will happen on re-entry from orbit.  If Starship cannot stand up to the stresses of a 15 km 'hop', then it will be unable to handle re-entry.

If the 15 km flight is successful, then Musk has said that the next step is orbit.  I don't think  Starship will be able to fly to 160km and still have enough fuel for a retro-propulsive burn, and the first stage (Super Heavy) has only just started construction, so Musk may just mean a flight to the Kármán line (100 km above the Earth) which is the conventionally accepted definition of where space begins.  But Super Heavy may be finished early next year, and genuine orbital flight will begin.    For faster re-entry from orbit, Starship will need a heat shield made of ceramic tiles and this will be when they start testing them.

If this works, it means that regular launches with payload will start soon after.  In a video from the Mars Society's annual conference, Musk hinted at a new timetable for Mars, with unmanned flights starting in 2024, instead of 2022.  (Mars is in opposition in December 2022 and January 2025) But if Starship has proved itself be safe, we may yet have crewed flights in late 2022. Starship is so cheap that the fleet heading to Mars could take 6 or 8 cargo Starships as well as 3 or 4 crewed ones.  

We shall see.  The probability is high that something will go wrong, delaying the whole timetable.  But I hope it doesn't.  I want to see the vids as the first humans on Mars open the hatches and look out on the red planet's surface.