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Take a few minutes today and Google 'Gemini Series'. This is what Burt Rutans craft is compareable to. The early Gemini rockets did not achieve orbit. The went up, and came back down again.

All manned Gemini missions achieved orbit. I think you're thinking of Project Mercury. The first two manned Mercury flights (Freedom 7 and Liberty Bell 7) were 15-minute suborbital flights. Later Mercury missions were launched on more powerful booster rockets, and they achieved orbit.

Project Gemini, on the other hand, was far more advanced than Mercury. It was the proving ground for technologies and procedures that would be used in the Apollo moon landings (rendezvous, space suits, long duration flights, etc.). Gemini XI reached an altitude of 1368 km, which is several times higher than even the Space Shuttle can reach.

Take a few minutes today and Google 'Gemini Series'. This is what Burt Rutans craft is compareable to. The early Gemini rockets did not achieve orbit. The went up, and came back down again.

All manned Gemini missions achieved orbit. I think you're thinking of Project Mercury. The first two manned Mercury flights (Freedom 7 and Liberty Bell 7) were 15-minute suborbital flights. Later Mercury missions were launched on more powerful booster rockets, and they achieved orbit.

Project Gemini, on the other hand, was far more advanced than Mercury. It was the proving ground for technologies and procedures that would be used in the Apollo moon landings (rendezvous, space suits, long duration flights, etc.). Gemini XI reached an altitude of 1368 km, which is several times higher than even the Space Shuttle can reach.

Neil Armstrong was in the Navy from 1949 to 1952. He wasn't in the military at the same time as he was an astronaut, but he was once in the military.

See this page for more information

Thanks for your corrections.

AoA doesn't really come into it much. Once you enter the atmosphere, you're losing huge amounts of velocity. At hypersonic velocities, L/D ratios are awful, pretty much no matter what your AoA is.

It depends. Obviously, the atmosphere is much thinner the higher up you go. The sooner you can obtain a flight envelope (rather than the "falling refrigerator" configuration of the shuttle), the longer you can take in your descent. Keep in mind that the Space Shuttle intentionally bleeds off a lot of speed by doing a supersonic slalom on the way down. This is such a difficult flight path, that only one human has ever flown reentry on manual. All other flights were handled by the computer. There's a nice description of reentry here.

At least two designs other than the shuttle's current one were considered:

On faster descent:

Despite these arguments that eventually prevailed, at least one straight-wing design was prominent for a time, in part because of its designer. Max Faget, the chief engineer at NASA's Manned Spacecraft Center (later renamed the Johnson Space Center), drew up plans for two straight-winged vehicles--one an orbiter and the other a booster stage--that rode piggyback and were both piloted and fully reusable. [snip] Faget argued that his design would enable the orbiter to return to Earth at a sharp angle that would significantly heat only the orbiter's lower surfaces (Faget, pp. 52-54)

On slower descent:

If it weren't for the payload bay requirement, a lifting body configuration might have worked well. Lifting bodies could have been a good compromise between ballistic capsules and delta- or straight-winged vehicles. They are lighter, have simpler structures, and encounter fewer reentry heating problems than winged vehicles. Lifting bodies have better lift-to-drag ratios than ballistic capsules, which enables them to be piloted more accurately (Peebles, December 1979, p. 487). Lifting bodies had even been considered for the Apollo command modules (Peebles, November 1979, p. 439). Throughout the 1960s and early 1970s, NASA and the Air Force had conducted significant research on various lifting body programs such as the X-23A and the X-24A, demonstrating, among other characteristics, the maneuverability of wingless vehicles (Reed, pp. 129--131, 140).

Source

I don't have a link at the moment, but descent was a big problem in the early rocket plane experiments. If they descended too slowly, they'd lose their flight envelope and become difficult to control. But if they descended too quickly, the craft would heat up at an incredible rate.

Does this link help? NASA is surprisingly honest on what went right and what went wrong with the program. The one thing they don't cover is that it was Nixon's decision to scale back the space program and merge it with the Air Force. After we reached the moon, Nixon decided that having a low cost "token" space program would be enough.

The truly amazing part is the work that the engineers did. They were given a set of impossible requirements that were all at odds with one another, and the engineers still managed to develop a craft that met the specs. In almost all ways, the Shuttle problems were political, not technical.

There's some info on the Air Force's desires for the Shuttle on NASA's History Site. From the article:

One Air Force requirement that had a critical effect on the Shuttle design was cross range capability. The military wanted to be able to send a Shuttle on an orbit around the Earth's poles because a significant portion of the Soviet Union was at high latitudes near the Arctic Circle. The idea was to be able to deploy a reconnaissance satellite, retrieve an errant spacecraft, or even capture an enemy satellite, and then have the Shuttle return to its launch site after only one orbit to escape Soviet detection. Because the Earth rotates on its axis, by the time the Shuttle would return to its base, the base would have "moved" approximately 1,100 miles to the east. Thus the Shuttle needed to be able to maneuver that distance "sideways" upon reentering the atmosphere.

Given a choice between straight and delta wings, the latter perform much better in terms of cross range capability. Delta wings produce more lift at hypersonic speeds, enabling more maneuverability (Heppenheimer, p. 220). Given the requirement for cross range capability, a delta-winged vehicle became the clear choice. Additionally, delta-winged vehicles do not heat up as much as straight-winged vehicles during atmospheric reentry (Draper et al., p. 26), thus decreasing the need for expensive and potentially heavy thermal protection systems, although the thermodynamics are too complex to cover fully in this paper. Moreover, some aerodynamicists argued that delta-winged vehicles were a proven technology that provided good balance, stability, and aerodynamic control (Draper et al., pp. 29, 35).

Now you know why the Space Shuttle has stubby delta-wings for hypersonic flight. I'll see if I can dig up some other links.

Not at all. I assert that SpaceShipOne has many design similarities to NASA's M2-F2. Looking at the profiles of each craft (which is why I linked to the picture), you can see how the general shape (at least) is very similar.

SpaceShipOne undeniably benefits from NASA research, if not for the prior art, than NASA's freely available research on space exploration.

Clearly this is a great success in the commercial space movement.

Let me begin by saying that SpaceShipOne is a development on clearly establablished NASA research, as NASA have demostrated a prototype which displays the same functionality.

NASA have always maintained that their research is for the benefit of all mankind. Here is where we see the benefits of their tax funded research, in commercial endeavors.

The question to ask is about NASA's place in the future. As the first (of hopefully many) endeavors against a governmental monopoly on space, one must wonder if this is the beginning of a trend. If so, how long before commercial interests take over NASA in R&D, budget and achievements?

To wit; could the first man on Mars be a private individual?

it's not a matter of height, it's a matter of speed.

Here is a nice orbital velocity calculator.

Getting up to that speed is not the only problem, you have to loose all that kinetic energy before you land, unless you fancy spreading yourself thinly across a continent.

We're pushing the bounds of the possible! Daring the unknown! Challeng- uh, no... wait... it's not 1963 and we've kind of been over this before.

Wake me up when they get into orbit, k?

Nope. STS-1 launched in 1981.

NASA's space program is far more noticeable than their aeronautics endeavors, but this is not a reflection of the amount of work done in either area. Their ASRS program is an important part of aviation safety research. They are examining ways to make quieter jet engines. They are working on ways to improve the efficiency of our air traffic control system.

You seem like a concerned citizen. If you want to find out more about what NASA is up to, I recommend you start by reading their aeronautics blueprint.

• Valentina Vladimirovna Tereshkova First woman in space.
• Guion Bluford First african american in space.
• Laika first of earths inhabitants in space (baring alien abductions, etc).
• Tito first tourist.... Shuttlesworth - first guy from his whole continent...

• Valentina Vladimirovna Tereshkova First woman in space.
• Guion Bluford First african american in space.
• Laika first of earths inhabitants in space (baring alien abductions, etc).
• Tito first tourist.... Shuttlesworth - first guy from his whole continent...

To Mike and the rest of the SpaceShipOne crew, best of luck tomorrow.

great interface for number visualization

I think the same guy who did the smartmoney maps did this one also:
visualize a musical piece's relation to parts of itself

make your own galaxies as part of search

hrm, they don't all seem to be working properly now with mozilla 1.7 and java 1.4.2_04-b05 although they worked fine a couple years ago. I had the same sort of problems with smartmoney which is why I didn't buy a subscription.

The View from Everest

This camera operates in many ways the same as the cameras on Viking I and II - a rotating platform presents a line of pixels to an imaging element - in Viking the system went a bit further in that the line of image data was scanned by a mirror to direct it to one of several photodiodes to image the different parts of the spectrum.

The advantage to a system like this is that number of pixels in the axis scanned by the slit can be increased by finer control over the stepping motors driving it. While at some point you end overscanning scene (each strip covers much of the same ground as the previous strip due to the angle of view of the imaging element) you do gain some information by that overscanning - so you do increase the resolution in that axis.

Now, a camera like this is USELESS for motion photography (so all the one-handed typists drooling over pr0n are S.O.L.) - in fact the Viking camera team created a picture of themselves while they were testing the camera on Earth - one guy got in the shot five times by waiting until he had been scanned, then running around behind the camera, getting into position again, and being scanned again.

HOWEVER, I'd love to have a camera like this for taking pictures of places like The Grand Canyon, Bryce Canyon, the view from Pike's Peak, and other scenic vistas - there is simply no way to capture these places with anything like a normal camera.

Imagine if a camera like this could be located at the summit of Mt. Everest!

Or better still, Mare Tranquillitatis

Compared to the seemingly crappy 0.000005 Megapixel cams they put on those things now..

Contrary to popular belief, the Cassini missions are run by JPL, which is a federally funded research facility that has close ties to NASA, but isn't actually a part of NASA.

Excuse me? What are you talking about?

about jpl

Well, wiseguy, FYI, I did notice you used the word "Kansas", and that you were using the acronym KSC. As space centers go, KSC stands for the one in Florida, and not for anything in Kansas, as shown by the page www.ksc.nasa.gov. I thought that would be clear from my posting, but I must have overestimated something.

Doubling the fuel means doubling the weight that has to hoisted to orbit, means doubling the price. I hate to be the one waving dollar signs here, but yes Virginia these things do cost money.

Well, you were the one who said that the nuclear rocket plan "merely" saved fuel ... But anyway, the whole point of Mars Direct is that it harvests the fuel for the return trip on Mars so you don't have to bring it all the way from Earth. As you point out yourself, there's a huge cost saving right there. (Oh, and I should also point out that Mars Direct tries to minimise the number of launches from Earth; you only need one Saturn V class booster per spacecraft - that is to say three in the limited scenario I originally suggested. True, we don't have any Saturn V class boosters any more (unless you count the Russian Energiya which I don't think has been used in many years) so to be fair development costs for that should probably be included in Mars Direct's costs. It could also be done with smaller boosters and in-orbit assembly, which also brings costs and risks.)

I don't know what you do at night; all I know about you is what you write, and while your objections are not all irrelevant, they are not the end of the story either. They can be solved, and clever people have suggested clever solutions for them. We need a can-do attitude to get there, not a can't-do one.

Also, I never said anything about whether going to Mars was more worthwhile than curing world hunger; I was merely responding to your assertion that it would be too difficult to build a factory on Mars to produce propellent. I just wanted to point out that the best plans we have don't require astronauts to do this, and I got flamed for my troubles. But I will point out that we can do both (that is, both go to Mars and cure world hunger or whathaveyou); people always bring this false dichotomy up in relation to space travel but at the same time seem to ignore the massively wasteful spending on military hardware (even if you accept the need for a powerful military, annual cost overruns alone on large projects would fund NASA ten times over - yes, I just plucked that figure from nowhere, but its something like that). Mars Direct m

Ok... Well when I submitted this story I forgot to include links to the Stardust Website, Wild 2 Photos, and some interesting Wild 2 Stereo Photos (2.0 MB). Best of all.. there's minimal reading, just pretty pictures. Enjoy :)

Ok... Well when I submitted this story I forgot to include links to the Stardust Website, Wild 2 Photos, and some interesting Wild 2 Stereo Photos (2.0 MB). Best of all.. there's minimal reading, just pretty pictures. Enjoy :)

Ok... Well when I submitted this story I forgot to include links to the Stardust Website, Wild 2 Photos, and some interesting Wild 2 Stereo Photos (2.0 MB). Best of all.. there's minimal reading, just pretty pictures. Enjoy :)

WTF!? "Van Halen" belt... I think you meant Van Allen belt. Been to too many concerts I see.

Here is the Apollo 15 launch in Real Video and MPEG

Enjoy!

Here is the Apollo 15 launch in Real Video and MPEG

Enjoy!

First off, I'm not a rocket scientist, just an interested amateur - so this may get a little rough.
The answer depends greatly on whether the lauch is orbital like most satellites or suborbital like the x-prize is.
Launching from altitude means that there is less drag, it also means that the engine nozzles can be optimized for efficient operation at low to zero pressure (Aerospike nozzles are meant to work efficiently at all pressures but are still experimental.)
Orbital launches have to reach orbital velocity (somewhere around 10,000 M/S for LEO, don't have the figure handy unfortunately) this is what the east-west launch helps with. Most of the two stage to orbit designs I have seen have a supersonic lower stage to give the upper stage as much of a runup as possible. An interesting example of this is the proposed RASCAL satellite launcher.
I believe that polar launches are used so that satellites can map the entire surface over a series of orbits.

Come on now, you really think Carmack would use something as old as Doom for this? I would bet he'd use a high tech simulator from NASA.

The Van Halen belt? Someone spent too much time listening to hair metal in the 80's. You mean the Van Allen Belts

"KSC is a private sector organization in the middle of Kansas (more or less)."

Hold on, are you talking about the same KSC that I'm thinking of? That already has an actual saturn V rocket on display inside of an air-conditioned building together with the actual launch control room equipment? Note that the KSC I'm talking about is in Florida, not in Kansas, not even more or less...

You don't scratch build the factory on Mars. You build it on Earth, send it to Mars 18 months before the astronauts, let it churn away for that time, lots of consumables for them by the time they get there. In case of problems, you send an identical automated factory in a separate ship at the same time the manned ship leaves, which will arrive at roughly the same time. Seriously, the GP is correct; it's not that hard to get there using Mars Direct; see here, here and even here (NASA adopted a more conservative version of Mars Direct some time ago). Or read The Case for Mars .

I was curious, so I looked up the output of the Shuttle's main engines compared to the Saturn V main engines.
The shuttle's main engines produce a maximum of 488,000 pounds of thrust. The Saturn V main engines produced a total of 7.5 million pounds of thrust, or 1.5 million pounds per engine. So it looks like each engine on the Saturn V was about 3 times as powerful as each of the main engines on the shuttle.
Oh, the solid rocket boosters on the shuttle each produce 3.3 million pounds of thrust.

I wonder if they'll have any involvement. After all they single-handedly restored the Liberty Bell 7 (their link here. And also helped with the restoration of the Apollo 13 as well. When you tought of Kansas, you probably didn't think of space now did ya?

It took Spirit and Opportunity a mere three months to get to Mars.

According to this NASA page, the fast transit considered is only two months. Most proposals I've seen are for 3 to 6 months.

You can estimate your chances of survival using NASA's model (PC only).

You can estimate your chances of survival using NASA's model (PC only).

If they make this work then in short order they could have a station with more inhabitable volume than ISS for a fraction of the cost.

That's great, but how are you going to get people to your new station?

To put people into space you have to send them up on a man rated launcher. The only people with those right now are NASA, RKA (Russia) and CNSA (China). There are no private launchers capable of putting people into orbit and won't be for a considerable amount of time.

I'm an idiot, sorry, you are absolutely right.

I don't think it was ever claimed that Voyager has reached the heliopause. They claimed it has reached the inside of the termination shock boundary which is expected to take a couple of years to traverse. After which, the craft will be considered to be inside the heliosheath which itself may take several years to pass, where it will only then reach the healiopause and transfer into true interstellar space.

I don't think it was ever claimed that Voyager has reached the heliopause. They claimed it has reached the inside of the termination shock boundary which is expected to take a couple of years to traverse. After which, the craft will be considered to be inside the heliosheath which itself may take several years to pass, where it will only then reach the healiopause and transfer into true interstellar space.

For those looking for a more in depth study of the pioneer missions to the outer planets, this book published in the late 70's (now fully online) is truly a hidden gem from NASA's site. It details every last design aspect of the spacecraft in extremely high detail. We've certianly come a long way in ~30 years from grainy washed out Pioneer photopolarimeter images to super high resolution ultrasharp CCD images from Cassini.

For those looking for a more in depth study of the pioneer missions to the outer planets, this book published in the late 70's (now fully online) is truly a hidden gem from NASA's site. It details every last design aspect of the spacecraft in extremely high detail. We've certianly come a long way in ~30 years from grainy washed out Pioneer photopolarimeter images to super high resolution ultrasharp CCD images from Cassini.

For those looking for a more in depth study of the pioneer missions to the outer planets, this book published in the late 70's (now fully online) is truly a hidden gem from NASA's site. It details every last design aspect of the spacecraft in extremely high detail. We've certianly come a long way in ~30 years from grainy washed out Pioneer photopolarimeter images to super high resolution ultrasharp CCD images from Cassini.

For those looking for a more in depth study of the pioneer missions to the outer planets, this book published in the late 70's (now fully online) is truly a hidden gem from NASA's site. It details every last design aspect of the spacecraft in extremely high detail. We've certianly come a long way in ~30 years from grainy washed out Pioneer photopolarimeter images to super high resolution ultrasharp CCD images from Cassini.

That is indeed a cool link, but don't forget that it only shows cloud-to-ground lightning, which is only about 10% of all lightning. Vaisala sells that lightning data to power companies so they have a vested interest in filtering out all intracloud lightning. This also means that the data is great at telling you that an established storm is coming, but new storms usually only produce intra-cloud lightning before they get strong enough to produce cloud-to-ground.

For cool non-realtime stuff, check out these satellite-derived summaries.

They give an interesting perspective on lightning distributions. There's more lightning over the North Pacific in the winter than the summer, for example (probably because there are more storms).

The part of lightening study that fasinates me is the discovery of sprites,a part of a lightening strike that moves spaceward.

Here is a pic of a sprite.

This is linked to in a longish article. See under Recent Developments.

The part of lightening study that fasinates me is the discovery of sprites,a part of a lightening strike that moves spaceward.

Here is a pic of a sprite.

This is linked to in a longish article. See under Recent Developments.

$250/ton launch costs to low earth orbit sort of change things a bit. Even the Space Elevator no longer makes sense competing with something like this, and the problems with blimp-to-orbit projects are a hell of a lot easier to solve than the problems of getting carbon nanotube technology ready to build ribbons long enough and strong enough to carry freight by the ton to orbit.

They make projects like solar power satellite networks look feasible. BTW, NASA's numbers that pointed toward feasibility were based on hypothetical $400/kg launch costs. The numbers look a lot better at $250/ton.

Given the risk-averse nature of modern corporations, this still would be a hard sell.

Perhaps government loan guarantees, liability caps like the ones given to nuclear power producers, and guarantees of X-million pounds of payload contracts to companies who prove the ability to deliver to orbit at $X or $XX dollars / pound would make it a lot easier to get private capital on board.

More of that sort of thing is discussed on my technology page, check the sig.