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Comment by martythemaniak | Hacker News Reader

I played a few games of Kerbal Space program recently, so I can understand what's happening a little better now.

I'd love to have a place somewhere where I can "watch" launches in a way similar to KSP's map view. You would be able to see the rocket, including it's essential info (altitude, speed, the ball thing) and also be able to see the manoeuvres they do.

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Man, I hope SpaceX has far more success with their launches than I do in KSP, otherwise Orlando is going to have quite a fireworks show.

I'd settle for just seeing things like their delta-V maps. It's one thing for me to make my own for KSP missions, it's another to see one for a real world situation.

While I'm a mere Kerbalnaut myself, here is some napkin math that almost checks out. For a GTO payload, the Falcon 9 http://www.spaceflight101.com/falcon-9-v11.html has:

  S1 Mass full: 490,300kg (that's both stages, fuel in both, plus the fairing and payload)
  S1 Mass empty: 100,300kg (S1 mass minus stage one fuel)
  S1 ISP: 282s (sea level) to 311s (vacuum)

  S2 Mass full: 82,300kg (second stage, fuel, fairing and payload)
  S2 Mass empty: 11,500kg (S2 mass minus stage two fuel)
  S2 ISP: 340s (unspecified)

According to this delta-v calculator http://www.strout.net/info/science/delta-v/, that would give delta-v values of:

  S1 delta-v: 4388m/s to 4840m/s
  S2 delta-v: 6562m/s

  Total delta-v: 10.8km/s to 11.3km/s

For GTO, Wikipedia http://en.wikipedia.org/wiki/Delta-v gives a delta-v value of 11.8km/s to 12.5km/s, so these numbers fall just under the low end of that range. However, maybe the highly elliptical orbit that this launch is aiming for is slightly more efficient than whatever orbit is assumed for that chart on Wikipedia.

I agree. NASA's MAVEN launch last week had a fantastic live stream that included commentary plus telemetry data, it was space nerd heaven.

http://www.ustream.tv/recorded/40966344

I couldn't find a better video, that one cuts off 6 minutes into the launch, before they get to the good part where the telemetry shows orbital information. The stream went on for at least 45 more minutes, I grabbed a screenshot 51 minutes into the launch:

http://imgur.com/LUD6XUk

The amount of learning one can do on KSP alone shouldn't be underestimated.

You know you're onto something when you start doing Delta-V calculations while designing your rocket and talking about bi-elliptic transfers and aerobraking on the forums.

It is not enough to become a rocket scientist, but it is enough to understand the basics.

And, as per another comment, you can even begin to understand some of the telemetry data, even if in an intuitive sense.

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