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Comment by p1mrx | Hacker News Reader

At least we know Rocket Lab's webcast uses real telemetry, unlike Blue Origin, where they break the laws of Physics by pausing at 0 MPH: https://youtu.be/sUEj4dxPMbI?t=2658

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I like how a 1 second pause in telemetry makes you so certain that Blue Origin is fraudulent. Anyway, what is the point of your comment on this thread anyway?

I don't think Blue Origin as a whole is fraudulent, just that they're not showing real telemetry data. By way of comparison, I think it's commendable that Rocket Lab's stream was accurate enough for viewers to see the failure occurring live.

Faking the data seems like more work than just showing the data they are getting from the rocket which is why I'm personally skeptical.

Re-watching the numbers during the Blue Origin launch, it would've been tedious to fake the jumpiness using a pre-rendered animation, so perhaps the number fudging is limited to a "pause at zero" hack. Still, the presence of a "marketing telemetry" algorithm makes it seem less trustworthy for determining whether a failure occurred.

It shows that they're not showing unfiltered telemetry data, but it absolutely does not prove it's not real at all. Interpolation, rounding, sampling frequency in combination would easily explain this.

Not to mention that the speed freezes quite frequently at other points in the video...

Yes, I was impressed by Rocket Lab telemetry too. The picture is freezing and I can see by numbers that vehicle gone ballistic...

New Shepard is a suborbital rocket. It reaches apogee (velocity drops to zero), and drops back to land propulsively.

It’s possible it experiences zero-G for more than just a few milliseconds at its apogee. Hence the 0mph velocity.

You fell victim to one of the classic blunders: conflating velocity with its derivative.

The (approximately) zero-G period lasts for minutes, not milliseconds, and during that time, the velocity changes by 9.8 m/s (22 MPH) every second. The velocity should not pause at 0, or any other value.

22 mph per second is an abomination of a mixed unit I'd never heard before, but it's actually much more intuitive to me than the standard 9.8 metres per second per second.

Maybe we can compromise on 35 km/h per second though.

I wouldn't normally use MPH/s, but it fits the units in the Blue Origin video.

New Shepard is not traveling perfectly vertical, there's always a horizontal component so the velocity will never be zero. Even if you fly up in a perfectly vertical line, you'll gain horizontal velocity as you climb as the Earth's surface moves away from you from it's rotation.

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