sevenperforce

MOST BEAUTIFUL SHOT OF THE FLIP I HAVE EVER SEEN All CRS missions will be RTLS from now on.

Technical webcast is nothing but the regular webcast without voiceover. No differences in shot or telemetry. Sooty rocket lifting off...beautiful sight! Through Max-Q. MVac chilling.

The new strongback is NICE. They are going over the upgrades now.

We've got soooooooooooooot!

Yeah, just a touch of off-plane inclination will help keep it out of intercepts, but it will still cross Earth orbit now and then. But computing a trajectory which has no Earth encounters for millions of years is not that hard to do. Not when you're SpaceX. Just need a fast computer. HYPE TRAAAAAAAIN

You were born with a certain set of predispositions and aptitudes, which will not change. However, you can take steps to train yourself to think analytically, to solve problems, to recognize patterns and non-patterns, and so forth. This is not an easy thing to do, though. The brain's neuroplasticity can really only be altered by one thing -- practice. By repeating the same actions over and over (optionally with the help of a reward-pathway stimulant like caffeine), your brain learns to prioritize and expand certain connections. You should try getting up and doing the same things at the same time every morning. Set an alarm, practice getting up immediately, do the same routine every morning. Solve a sudoku or crossword puzzle if you have a morning public transit commute. Human capacity for memorization is pretty amazing, but again, it MUST be trained. Memorize stuff. Start with the periodic table of elements -- there's Tom Lehrer's famous version, which makes for a nice party trick, if nothing else. Practice mental math; learn how to determine what day of the week any date in history is, and amaze people when you tell them what day they were born on. If you have the opportunity, take a college algebra class or an introductory calculus class. Find a study group, ask for help, and ace the class. If you really want to double down, take a college physics class. Skip the "physics for nonmajors" and go straight to technical physics I. Read voraciously. Gradatim ferociter. Try to exercise regularly. We evolved in a world much more active than the one we inhabit today, and your brain is connected to your body, so it will reap the benefits of exercise. Avoid hacks and hype trains. If it's easy, it won't alter your brain. If it's tough, and takes a lot of practice, it will. The only legit "hack" is caffeine. Caffeine hijacks the reward pathways in the brain and helps form new neural connections associated with concurrent activities. However, the effectiveness of this does not scale with the amount of caffeine you ingest, so don't live off espresso. Instead, try to drink a limited amount of caffeine (tea is fine if you don't like coffee) at the same time every day to reinforce the routines you want to practice.

Yeah, the thrusters on his feet provide the primary impulse for flight; the ones on his hands are more like verniers. Remember, however, that the suit also has hundreds of actuated control surfaces. Presumably, JARVIS (or whatever other onboard supercomputer he has) moves the control surfaces and enhances his suit's rigidity as needed. The legs of the exoskeleton are most likely locked in place during boost flight so that the impulse is transferred properly to the entire suit.

Just reflew this with a full tank (launch mass: 8.18 tonnes) and it reaches LKO with 721 m/s of dV to spare. Or 595 kg of payload, if you had a place to put it.

Final entry. I challenge anyone to beat this. Reaches orbit with no trouble at all. Not going to place bets on coming down in one piece, though.

All right, I'm tired of seeing all these monstrosities, so here's my minimalist entry. Ten parts. 10.1 tonnes. One kerbal. Makes orbit easily, once you get it off the ground. You can pack enough fuel into it to reach Munar orbit, though I haven't tested landing yet. As you can see, the ramjet is attached to the rear node of the LV-N, then clipped inside it. Which feels cheaty, but oh well. Really cuts down on drag nicely, though! The wing is also clipped across the intake-cum-fuselage, and the single elevon is clipped through both engines. This is only possible because the large wing's center of lift is exactly at the same point as its center of mass, and its center of mass does not shift as its fuel is drained. Together, the single elevon and rear-mounted canard provide a surprising amount of pitch and yaw authority, though the only source of roll authority is the reaction wheel inside the cockpit (which is drained of monoprop, for obvious reasons).

I have a fifteen-part LF-only SSTO that can put two Kerbals in LKO with 2.6 km/s of dV remaining. Can probably get it down to 11 or 12 parts but it would require some overly-creative part-clipping. Roll-out mass is 18.93 tonnes. This drops to 14.8 tonnes if I drain everything but what I need to reach orbit.

Or hey, how about this -- lowest part count to get at least one Kerbal into LKO with an LF-only HTOL SSTO?

No chutes on the booster.

Hella necro there dude

Not too terribly hard, but sure, it's somewhat of a challenge. Why don't you add scoring of some kind? Like "lowest launch mass wins" or "highest payload fraction wins"?

Methinks that the lack of grid fin guidance makes for a much less pinpoint trajectory. F9 Block 5 is supposed to have something like a 1:1 glide ratio; that is a LOT of lift for what is essentially a plummeting telephone pole. Grid fin control authority probably makes up the majority of Falcon 9's trajectory adjustments. In contrast, the New Shepard is focused more on touching down safely/smoothly than on pinpointing a landing spot. I am also 100% certain that SpaceX pays more money to its programming/algorithm department than Blue Origin does.

In theory, there's a way for an object to "catch up" to itself, but it's rather hackneyed. Consider an object traveling at a really ridiculously high percentage of c which emits a photon traveling at some angle θ. If that photon happens to pass by the edge of a very massive lensing object which bends its trajectory by more than 2θ, then I suppose it would be possible for that photon to be diverted back such that it would cross the path of the emitting object. In order for this to happen, the velocity vector of the object would have to be perfectly coplanar with the lensing object, and the increase in path length taken by the photon would have to be greater than the difference in speed between the photon and the emitting object.

String theory and quantum gravity are not currently robustly falsifiable, but it is an open problem in physics. There are people working on it. There are mechanisms whereby they could be partially falsifiable, or where certain versions could be falsified. For example, the existence and potential detection of magnetic monopoles is a prediction of several versions of string theory. Attempts at detecting monopoles have thus far been unsuccessful, which falsifies certain versions of string theory which predict a high density of detectable monopoles. However, there are other versions which predict lower densities, which are not falsified. There are certain versions of quantum gravity which predict asymmetry in particle energies under certain circumstances. These predictions were not immediately testable or falsifiable at the time they were made, but now there are ongoing experiments at the Pierre Auger observatory and elsewhere which could falsify these predictions. Asking whether a theory itself is falsifiable is a little bit tricky. What can be shown to be falsifiable (or not) are the predictions made by a theory. A theory which makes no falsifiable predictions is probably not a good theory; a theory which makes concrete, agreed-upon falsifiable predictions is a much more useful theory. Wildly speculating that an asteroid's tumble pattern means it might be an alien probe is so far from producing testable/falsifiable predictions as to be laughable.

Huh what? **starts reading thread**

The least dense known liquid is some methyl-butene group hydrocarbon, at 650 g/L. The densest possible gas would be uranium hexachloride at 19.5 g/L. So, no. If you used an incompressible liquid and put the whole affair under pressure, there's a chance you could get the gas to be denser than the liquid. But probably not.

That question doesn't compute.

Hot damn.

Actually, yes. It's rare, but it can happen. A distant galaxy cluster bends light from even more distant objects around itself. If we are nearly lined up with both objects, then we can sometimes see multiple images of the same object. When we are perfectly lined up, this produces an "Einstein ring": The blue ring is the image of a single object exactly on the other side of the central cluster. When we're almost (but not quite) lined up and the mass distribution of the lensing object is just right, we get multiple discrete images. The most famous is the Einstein cross: The light from the actual object takes four discrete paths to wrap around the galaxy on its way to us. Since those paths differ in length, what we are seeing here is a single object at four different points in time. The image on the left is the youngest, followed by the image on the bottom, then the one on the top, and finally the one on the far right. This could get really interesting if, for example, there was a hypernova in the actual object. We'd see an extra flash of light first from in the left image, then in the bottom, then the top, then the right, based on the difference in the path lengths for each image. If I recall correctly, this has recently been used to watch a "replay" of a supernova. We saw a fairly close supernova in one image and recognized that we could expect it in the other image just a few hours later, so we had time to train several telescopes exactly on the spot and get some really good data. Now, the maximum amount of time difference between any two images is a function of the ray path length, so there's a limit to how much delay is possible. And light wouldn't be able to curve around a 180-degree lens and come back to us, so we can't image prehistoric Earth that way.

Since no one has yet done a "rocket only recovery", allow me... Quick and dirty, and I had a bit of margin left on both stages, but overall not a bad attempt. Comes in at 7.5% payload fraction with full recovery of upper stage (via chute) and first stage (rocket-assisted splashdown). 228.066 tonnes liftoff mass. Spry 2.5 gees off the pad...going to try and negate as much gravity drag as possible. Quick nose-over. My theory is that with a lot of thrust, I'll not only get lower gravity losses, but I'll also get a high apoapse quickly, to give me more time for the upper stage to circularize. Definitely got the "hot" part down. Staging. Four Darts give me a nice respectable TWR. Once I'm up to where I want to be, I'll do the final circularization with the single Terrier. Super lofted trajectory so I'm pointed way under the horizon to circularize. More lofted than is efficient, but it was necessary in order to get enough time to recover the first stage. The trick is to finish your circularization while the first stage is still above 70 km. Almost there. Orbit achieved! If I was pressed for time I'd wait to raise periapsis while I took care of the first stage, but I have plenty of time here. There's my orbit! Switching back to the first stage. Transferring prop from the locked upper tank to the lower one, to improve my CoM. Brakes out and here goes entry. Hot! Going to wait until I'm closer to terminal velocity so I don't waste prop. Here goes that three-engine landing burn! Any more engines than this and it would be hard to control on the fly...especially since I'm doing this manually. Straightening out... Level and dropping. Steady as she goes.... Splashdown! Nothing broken. Ready to recover! Now, back to the upper stage. Ready to jettison our cargo. Cargo out. Burning to deorbit. This should do it. Sending fuel forward to keep the engines out of the re-entry stream. Burning off my remaining fuel. That should do it! Opening up the bay doors for added drag. It actually flies in...almost. Chutes out! Coming in nice and easy. And down! All set. Screenshot showing 17 tonnes in orbit.

Depends on how realistic you want it to be. It's certainly possible, but Tweakscale would definitely help. If you want a VASMIR engine for the Hermes then you'd need a mod for that, but you can cheat and use a bank of NERVs and Dawns instead.