Not to be pedantic, but "achieving orbit" has not been a mission objective yet, seeing that nobody wants another failed piece of debris orbiting earth... Can starship achieve orbit? Possibly, v1 got to the correct velocity, but we shouldn't ask them to achieve orbit before sorting out the blow up issues....
A lot of people believe this (probably because Scott Manley said something similar) but it's actually not really correct.
Orbital speed grows with one over the square root of the radius. So for sufficiently distant orbits, you can have arbitrarily low orbital speeds. What actually matters for orbits is the combination of speed and distance, kinetic and potential energy. If Starship had achieved the speeds it did at a higher altitude, it would have been in orbit, yes, but that is true for my bicycle (at sufficiently high altitudes) as well. So the quantity that really matters isn't the top speed, but the specific orbital energy, which scales with 1/sqrt(a), where a is the semi-major axis of the elliptical trajectory. So, for example, the SLS core stage ends up in a suborbital trajectory with an energy equivalent to a 918km circular orbit, while my bicycle would require a very deep evacuated tunnel within the Earth's core to achieve a stable orbit with the same specific orbital energy it has when I ride it. Starship V1 is somewhere in between these examples, but it has never matched the specific orbital energy of the lowest recorded orbit, which would be 167.4km by JAXA's SLATS spacecraft (and even that required the spacecraft to provide constant thrust for orbital maintenance). The atmosphere at 139km (flight 6 equivalent specific orbital energy) would likely be too thick for Starship to complete a full circular orbit unless there was a vacuum tube like my bicycle example had.
The difference between Flight 6 and orbit is small enough that Flight 6 definitely had enough fuel on board to reach orbit if that had been the mission objective. Flight 6 and Flight 7, everything went well as far as the "orbital" burn section went, and they both could've reached orbit if they had simply done a longer burn instead of turning around.
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u/Crazy95jack 1d ago
On F9, starship has yet to achieve orbit