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Comment Re:Let's Get One Thing Fixed... (Score 1) 224

That is not the best strategy. It is better to push forward, take risks, and fail fast. You learn more from your failures than from your successes.

Indeed. But part of the problem is that SpaceX wants to simultaneously be taken seriously as a reliable delivery service, and push the bounds for rapid, radical cost reduction. Even rockets blowing up on the test stand or failing during experimental landings comes across as bad press for them - even if they expect to have low odds of success. I've seen way too many comments and articles along the lines of "OMG, SpaceX crashed a landing, how can you think about sending up astronauts with a company that unreliable?", when the concept of "fail until you get it right" was always the plan with those landings.

If I were to start a rocket company it'd be in two parts. The first would be something like "Crazy Karen's Discount Rocket Emporium", and would go for a total Kerbal vibe, down to crudely spraypainted "This Way Up" notes on the side of stages, duct tape holding things in place on test stands, any interviews given in totally unprofessional clothing, etc. The sort of company that you'd be more surprised when things work than when they fail. The other would be your standard stuffy boring professional institution and would have a partnership with the kerbal-esque company, making clear that they acquire "promising but immature" technology from the other side, then invest their engineering resources on turning it into a refined and reliable experience for their launch service customers. All of the risky research efforts would be done by the first side.

It's effectively the same thing, but it'd make the delineation that all rocketry companies strive for explicit. You move fastest by taking risks rather than trying to avoid all failures, but you try to insulate the risk-taking side from the actual experience you offer paying consumers as much as you realistically can.

Comment Re:Wow (Score 1) 182

That's not what people were complaining about in the video. What people were complaining about was that they were landing right next to an exposed, filled propellant stage. You don't land a skyscraper-sized fireball-on-a-stick right next to a half billion dollar tank of fuel. That aspect was clearly stylized.

Comment Re:not limitless (Score 2) 108

If I gave them the benefit of the doubt, perhaps it was strategic: price it high enough to limit the strain on their wireless network, but then similarly not so high that those who would actually use it and need it to be reliable are screwed over. Then sod off anyone who didn't like it. Not that I'd expect them to actually come out and say something like that.

Except it did go down. It completely collapsed under the load.

I understand the need and that if everyone brought their own hotspot that it would be completely useless. But that's not the way to do it. At $200, it sounds like gouging - especially when you consider they actually did active scans for unauthorized WiFi and escorted people out.

The problem is many - first, the price appeared to be gouging. Second, active WiFi scanning - granted, they didn't jam (which was what got the hotels in trouble) but escorted you off the premises so it was technically legal. Third, they could've offered suggestions that people use hard wire (USB) tethers or built-in WWAN modems to achieve connectivity instead of WiFI Most of the people there would be using tablets, laptops, etc, many models of which have WWAN capability either built-in through USB dongles. Or a USB cable to their phones (practically all smartphones allow USB tethering)

Because right now, it appears to be gouging. Which is why the FCC is irked. I'm sure if they simply suggested other methods, politely asked anyone using WiFi to turn it off and use non-WiFi methods, etc.

Yes, a lot of wifi causes problems - Apple has had problems during their keynotes because everyone had their hotspots on, but there are many ways it can be handled without it seeming like pure greed.

Comment Re: Impressive spec (Score 1) 111

Well would you look at that indeed! I argued for a loss of 348-282=66 sec in Merlin, and said that Raptor would be somewhat less of a difference but not much, as "chamber pressure has a positive but fairly weak correlation with ISP". You said 384 - "360-370" = 14-24 sec difference.

And the reality is... drumroll... the envelope please...

384-334 = 50 sec

I hope this has been a learning experience for you.

Comment Re:Wat (Score 2) 90

This is not correct. Juno is planned to do some limited observation/a> of the Galilean moons. It's a side mission, not central to it's focus (and Juno is anything but optimized for it), but it's one of those cases where, if you're there and you have the hardware...

Concerning Europa (remember that this was before the recent news):

The most significant opportunity for Juno to do Europa science would be to follow up on the plumes possibly detected by Hubble Space Telescope. Confirming Hubble's detection would be very scientifically valuable. Any information on the source location would be valuable. This science goal just may not be possible with the large distances from Juno to Europa, but we will look.

JunoCam or ASC can only detect plumes if they contain fine particles. The Hubble discovery (if real) only shows the presence of water vapor. We can predict by analogy to Enceladus that water vapor plumes will also contain particles. However, it is important to remember that the Hubble discovery was of gas, not particles. If the putative Europa plumes are Enceladus-like and do contain particles, they would not be as tall as Enceladus', because of Europa's higher gravity. Scaling for Europa’s gravity gives a maximum plume height of under 140 kilometers. To detect plumes, we need at least two pixels, so the image spatial scale would need to be better than 70 kilometers, at a relatively high phase angle where the particles would forward-scatter light to JunoCam and ASC.

To achieve resolutions better than 70 kilometers per pixel, UVS needs to be within 40,000 kilometers of Europa; JunoCam, 100,000 kilometers; and ASC, 170,000 kilometers. For the cameras, given the low expected height of the plumes, there is not much flexibility.

There are just four orbits that have Europa flybys that are closer than 300,000 km. Juno reaches the best available geometry in September 2017 as the rotation of the line of apsides brings Juno’s orbit close to Europa’s orbit:

2017-03-08 253,118 km
2017-09-19 264,043 km
2017-10-03 92,267 km
2017-10-17 204,654 km

Comment Re:So how is it supposed to communicate? (Score 1) 90

It's pretty limited what you can gather from individual grains captured at hypersonic velocities and analyzed with spacecraft-sized instruments. Certainly there was no "clear evidence of life" from Enceladus - although it showed us some very promising things about the potential habitability of its oceans.

Personally, I'm not a believer in the theory that wherever there's liquid water, there's life. First off, it'd make the Fermi paradox even worse, as water is bloody everywhere. Secondly, I think it's incredibly naive. The argument goes, wherever we find water on Earth, we find life, and whereever we don't, we don't, so we should expect that with the universe. But that says nothing about how life came about. Sure, LAWKI requires hydrogen, and water is the most convenient source of hydrogen, so obviously that's going to form the boundaries of where life has spread to. But where it's spread to says nothing about where it originated, or what it looked like when it did. We have no reason to think that the entire wet surface of Earth just spontaneously erupted into life; we certainly don't see anything resembling this in laboratory abiogenesis experiments. So what were the specific conditions that brought life about? I think it's a safe bet that they were rare. Quite likely no longer present on Earth, as Earth was a radically different place back then. And quite possibly rare in the universe as a whole. Little bursts of luck separated by great relativistic distances.

Indeed, bodies like Europa (and the many other bodies confirmed to or believed to have subsurface water in our solar system) should help answer these questions. I'm also exceedingly curious about what's gone on with alternative solvents and polymeric compounds, such as at the surface of Titan (I find the cyanide chemistry there fascinating, it seems to be extremely flexible).

Comment Re:Probably actually illegal (Score 1) 205

Probably, but I am reminded of the Microsoft/Stacker lawsuit. Stacker was a company that did on-the-fly disk compression for DOS systems. Microsoft met up with them and went through a lot of due diligence and saw a lot of Stacker's software code as part of a discussion about Microsoft licensing Stacker for the next version of DOS. They did not reach an agreement. Microsoft then incorporated a product in the next version that looked a lot like Stacker. Stacker sued and eventually won, but was already driven out of business by the time everything cleared court.

That was an interesting lawsuit - and I think in the end it was the compression algorithm they used more than anything - I had a beta version fo DOS6 and a legit version of DOS6 and the two wouldn't work together. I called Microsoft Support one day about that and they sent me a disk with a DoubleSpace to DriveSpace conversion utility that converted one format to the other.

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