Archive for the ‘Space’ Category

We Need a New (Cheaper) Upper Stage Engine

Saturday, December 22nd, 2012

During my run for the US Congress, I did quite a bit of research on space policy and in the process I found out something a bit surprising: one of the most commonly used engines for expendable launch vehicles is also one of the most expensive!
Every time a Delta-IV rocket takes off, it uses an RL-10 engine to propel its second stage to orbit.   The retired Delta-III also used the RL-10 for the second stage.  The RL-10 also powers the Centaur upper stage, used by Atlas rockets and previously used by the Titan series of rockets.  The Centaur, which uses one or two RL-10 engines has been in use since the 1960′s and is a mainstay of US high energy upper stages.  Six RL-10 engines were used to power the early versions of the Saturn-I rocket.

The RL-10 is also under consideration as a component of future launch systems such as the Space Launch System, which is currently under development by NASA and between one and four RL-10 engines are planned for the Advanced Common Evolved Stage, a new upper stage planned for future launch systems.

It’s not hard to see why the RL-10 is such a popular rocket engine.  As a liquid-hydrogen engine, it’s perfect for upper stages and for use as an earth departure stage.   It has excellent specific impulse, amongst the best of any rocket engines of its type.   It can be restarted in flight and is extremely reliable.   Early versions produced 66 kN of thrust and more recent variations now push 110 kN, which makes it perfectly sized to most payloads.

Considering that the RL-10 has been in production for a half-century and is one of the most prolific engine types, one might think it would not be terribly expensive.

However, the RL-10 is actually one of the most expensive engines out there, costing a whopping $38 million per engine.

Granted, space hardware is never cheap, but even by rocket engine standards $38 million a pop is extremely high.

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Curiosity Rover Discovery Was a Misscommunication

Thursday, November 29th, 2012

You may remember not long ago the news was humming of news that the NASA rover Curiosity had found something on important on mars.  It was reported that the discovery, which scientists were pretty confident of, was not being announced, because it was so absolutely astonishing and earth-shattering that they had to be 100% sure it was real and not an error.

The whole thing seemed strange:  if you were going to announce something major, why not just announce it?   If it was uncertain, why not announce that you saw signs of something but were not 100% sure?   Perhaps it could be attributed to the tendency of the press to gloss over the disclaimer of uncertainty, but given that fact, why announce anything at if it had not been verified?   Making an announcement of something, without saying what it was, seemed to defeat the purpose of waiting to release the information.

Needless to say, speculation ran wild.  What could it be?   Large amounts of liquid water?   Organic compounds?  Life?

Well, it turns out it wasn’t anything at all.   It was just some very ridiculous levels of misinterpretation by reporters.

Via Slate

Remember last week when we told you about how NASA’s Curiosity rover had reportedly sent back some very interesting data from Mars in the form of a soil sample that could be, in the apparent words of one of the mission’s leaders, “one for the history books”? Yeah, well, now NASA is saying that all the hype is actually just a giant misunderstanding between the scientist and the NPR reporter who interviewed him—a mistake that was then multiplied many times over by each news outlet (again, including us) who picked up the story.

Here, let’s have Mashable, which did the legwork to follow up on the original NPR report, explain (emphasis ours):

The quote heard around the world came shortly after [scientist John] Grotzinger explained that NASA had just received the initial data from Curiosity’s first soil experiment using a new Sample Analysis at Mars (SAM) instrument, which is capable of identifying organic compounds.

Naturally, the public assumed that this meant Curiosity had discovered a complex organic molecule. But while NASA does have the latest soil samples, the mission team tells Mashable that researchers haven’t determined that particular groundbreaking discovery. …

What Grotzinger was actually trying to convey is that Curiosity’s data over her entire two-year mission will further our knowledge of Mars more than ever before, making it a historical mission.

So to recap, Grotzinger was apparently trying to express just how excited he was about the entire mission, not about any one specific discovery; it is the sum of all of Curiosity’s past and future discoveries that he thinks will be historic. His particular choice of words—”This data is gonna be one for the history books”—however, along with the suggestion that his team was currently double- and triple-checking data it had received (something that is standard procedure) gave NPR the mistaken impression that there was something specific that NASA was eager to celebrate as a major discovery.

The original NPR report made it pretty clear that the reporter doing the interview, veteran science correspondent Joe Palca, thought Grotzinger was hyping a specific result:

Grotzinger says they recently put a soil sample in SAM, and the analysis shows something remarkable. “This data is gonna be one for the history books. It’s looking really good,” he says.

Grotzinger can see the pained look on my face as I wait, hoping he’ll tell me what the heck he’s found, but he’s not providing any more information.

While it’s a little odd that NASA’s communication team didn’t manage to quickly quash the rumor after the original report aired, Veronica McGregor, NASA’s news and social media manager for the Jet Propulsion Laboratory, told The Slatest late Tuesday night that they did their best to set the story straight.

So it seems that this was a case of the NASA spokesperson basically saying that the data from this mission would be something for the history books, not that any one given reading was so earth-shattering it would itself be one for the history books.

I have to admit I was suspicious of this from the start and got a strange feeling from it, and that’s why I didn’t say much about it.

I really wish the media had actually made an effort to confirm things like this more, but I also wish NASA had made more effort to clarify the situation. Apparently there were tweets to that effect from NASA and the Curiosity team, but clearly just tweeting it is not enough.

No Felix Baumgartner Absolutely Did NOT Jump From “Space”

Wednesday, October 24th, 2012

Last week sky diver Felix Baumgartner jumped from an altitude of 128,177 feet from a high altitude balloon, breaking the record for the highest altitude jump, which had stood since the 1960′s.   The jump was sponsored by Red Bull as part of the “Red Bull Stratos” project.

To be perfectly frank, it was a publicity stunt and it worked quite well in that regard.   I have no problem with that, and if it did inspire some additional interest in the physiological effects of high altitudes or the technical capabilities of high altitude ballooning, then that’s all well and good.   I doubt that there will be any really compelling scientific data from the event, but there might be some interesting information gathered.  If nothing else, it does push the capabilities of flight, which is always worth doing.

But there is one thing that bothers me:  It has repeatedly been stated that he jumped from “space”  Some call it “near space” and others “near the edge of space.”   In fact, high altitude ballooning now seems to be using these terms to pretend it is equivalent to actual space flight.   It’s not.

Gas filled balloons can reach the upper atmosphere, but they can’t reach space.  They depend on the buoyancy of their gas displacing atmosphere.  As such, they can never actually go above the earth’s atmosphere.  They may be able to reach altitudes above 99% of air molecules, but that is not space.

What is space, then?   That depends on what definition you choose to use.  There is no single bright line that indicates where space starts.  The atmosphere tapers off slowly and even in outer space, there are gas molecules floating around in a *near* perfect vacuum.   But regardless of the definition, whether you use the US Air Force’s arbitrary altitude of 50 statute miles, The Kármán line or the lowest practical altitude at which a satellite can maintain a stable orbit, it is much much higher than what any balloon can reach.

By any accepted definition:

  • If an air-breathing jet engine can function, you are not in space.
  • If you can remain aloft using aerodynamic lift, you are not in space
  • If you can get there using the buoyancy of a lightweight gas, you are not in space

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Why I am so saddened by Neil Armstrong’s Death

Sunday, August 26th, 2012

My admitted sadness from the death of Neil Armstrong has been received in a way I didn’t expect.   A lot of people have asked me why it was such a big deal and what made me feel so personally affected by it.   Obviously, Neil Armstrong was a great guy, a highly accomplished test pilot and astronaut and someone who was willing to take on a mission of unknown dangers and extreme demands.  But why is it so sad for me, personally?   I never knew him.  He was 82, hardly a young age, and he died peacefully of natural causes.  Great, heroic people die all the time, and sad though it may be, we can’t sit around getting depressed over it.

So let me explain my reason for such sadness:

The Apollo program is often held up as the prime example of the United States and indeed Western Civilization at its best.   A goal of the grandest of proportions was proposed and achieved, in a relatively short period of time, with overwhelming success.   Only six missions landed on the moon from 1969 to 1972, but those few missions provided some of the greatest photographs, films and accounts humanity has ever known.

The Apollo Program is over.  That in itself is not tragic, as it was expensive and could not last forever.   What is tragic is what the past forty years of space exploration have been.  Lacking leadership, necessary finances and a worthy goal, NASA has wallowed as an agency with an uncertain future.  No serious attempt to reestablish deep space exploration has been undertaken since the Apollo Program.  After Apollo came Skylab, a brief, but accomplished program using Apollo technology.   But would become so underfunded and ill equipped that once they ran out of suitable surplus Apollo hardware, they had literally no way of getting to the space station, resulting in it crashing to earth.  Next came the Shuttle, a spacecraft with the worthy goal of making access to orbit cheaper and safer, but built with such design compromise that it achieved neither.

Today we have an agency in crisis.  Plans for exploration in deep space have been scaled back and have a questionable future.   While the rover Curiosity has been a triumph, the future of unmanned space exploration is uncertain.  NASA has spent more than thirty years perusing projects that produced little more than artist conceptual drawings before being scrapped.  We cannot even send a man into low earth orbit, much less beyond earth orbit.

Neil Armstrong was the greatest icon of the glory days of space exploration, and his past is yet another step away from that past.  With every death, the Apollo program is pushed further into our past.  Though he was the best known, the first, the most iconic of the men to walk on the moon, there were others.  Twelve men explored the surface of the moon.   Most of them (eight in total) are still alive, although now one less.   These men are getting older, the youngest being in their late seventies.    This, of course, won’t last forever.   There may not be any left in ten years.    Walking on the moon has thus passed from human memory to history.

Those who walked on the moon so many years ago believed they stood on the cusp of a new age of exploration and that they would live to see many more missions.   Sadly, Neil Armstrong would not live to see humans return to the moon, at least not after Apollo-17.  He would also not live to see the space program once again receive the funding, recognition and mission goals it deserves.   He died in an era of turmoil and uncertainty for space exploration.   That is tragic.

Neil Armstrong August 5, 1930 – August 25, 2012

Saturday, August 25th, 2012

I was just shocked and saddened to learn of the death of Neil Armstrong at 82.   Rarely does a celebrity death truly effect me, but this one hit me like a ton of bricks.  What a great man and legend we have lost.

At the moment I don’t have a lot of time to write a post about this and to be honest I’m at loss for words.

He died due to complications from heart surgery that was preformed earlier this month.

For the first time in the more than five years that I have published this blog, I have decided to change some of the imagery in reflection of the loss of a tangible link to the most iconic great accomplishment of the United States.

Something Even More Amazing Than Curiosity on Mars

Friday, August 24th, 2012

There is now a new rover on the surface of mars.   It’s the size of a small SUV and has capabilities that surpass all planetary lander that came before.  With a suite of high power cameras, computers and transmitters, Curiosity can capture images of unprecedented resolution and even record high definition video, with the ability to cache images and video to two gigabytes of on board storage before transmitting them back to earth.  The rover is also equipped with a suite of analytical instruments, capable of determining the composition of surface materials or drilling and digging for deeper samples.

All of this is made possible by the 125 watt nuclear heat source, the latest generation of plutonium-238 radioisotope thermal generators.  Curiosity also has a pair of lithium-ion batteries which are charged by the RTG, enabling it to temporarily consume more than the 125 watt base output of the generator for short periods of time.  Previous rovers used solar panels to generate their on board power, and although the highest quality solar panels were used, they could produce up to 140 watts, but only under the best conditions and for a maximum of four hours a day.   The rover curiosity produces more than four times the previous two rovers did on their best day, and it does so every day.

So what could be a more amazing technical feat than the rover Curiosity?

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Mars Rover Lands PHEW!

Monday, August 6th, 2012

I don’t know if I’m the only one who felt this way, but upon seeing the first images come back from the most ambitious mars rover yet last night, my mood was less excitement and more relief.  It worked! It did not crash nor did it somehow fail to communicate to earth.  It made it down safe and sound.  The most dangerous part of the mission is finished.

The reason for my relief is not simply that the heavy rover required a complex and new method of landing, but simply the fact that so much can go wrong even with more conventional landings.   Not only could the landing go wrong, but the consequences would be enormous.   Had one of the earlier two rovers failed, there would have still been the other.  But the rover Curiosity is one of a kind.  There is no backup plan and all the eggs in this mission are in one basket.   The mission has cost over two billion dollars and used much of the available stockpile of precious plutonium-238.

In other words, we really only had one shot at this and had it gone wrong, the consequences for the US space program could have been enormous.   Unmanned deep space missions are a crap-shoot.  Even the best engineered and tested ones can and do fail.   Well, this one didn’t.   We’ve already got a few black and white photos back from it.   We’ll see what kind of discoveries it will make in the days, weeks months and hopefully years to come.   Now that we’ve let out the sigh of relief, it’s time to get excited!

Neil deGrass Tyson Gets Titanic Stars Changed

Monday, April 2nd, 2012

This is nearly identical to the talk Neil Tyson gave about the movie Titanic and how the stars were not accurate in the sky during the final scenes of the movie at TAM last year…


A little anal? I’d say so, considering how bad science and history are generally portrayed in movies. I doubt anyone actually noticed this besides Dr. Tyson.

Whatever your side on this, I also think James Camron did have a pretty good shoot-down for Dr. Tyson.

But he did get his way…

Via Contact Music:

Cameron Changes Stars In Titanic
Moviemaker James Cameron has re-edited a scene in Titanic showing stars sparkling in the night sky – after a leading astronomer told him the astral alignment was incorrect.

The director unveiled a 3D version of his multi-Oscar winning classic last month (Mar12) and he resisted the temptation to use its reworking as an excuse to cut scenes he’s no longer happy with.

But there was one shot Cameron felt obliged to alter, because a top stargazer informed him the astral pattern onscreen was incorrect for the night the liner sank in 1912.

The scene involves Kate Winslet’s character, Rose DeWitt Bukater, drifting on a piece of wood and gazing at the night sky as the disaster unfolds.

Cameron tells British magazine Culture, “Oh, there is one shot that I fixed. It’s because Neil deGrasse Tyson, who is one of the U.S.’ leading astronomers, sent me quite a snarky email saying that, at that time of year, in that position in the Atlantic in 1912, when Rose is lying on the piece of driftwood and staring up at the stars, that is not the star field she would have seen, and with my reputation as a perfectionist, I should have known that and I should have put the right star field in.

“So I said, ‘All right, you son of a b**ch, send me the right stars for the exact time, 4.20am on April 15, 1912, and I’ll put it in the movie.’ So that’s the one shot that has been changed.”

A Moon Base in Eight Years? Yeah, sure. Why not?

Sunday, February 12th, 2012

Recently US presidential candidate Newt Gingirch has been getting a lot of flack, especially from skeptics, because of a statement he made stamens implying that the US could and should establish a permanent lunar colony and do so by the end of his presidential term.� That means there would be about eight years from start to finish.

Crazy?

Well, whatever you think of Gingrich, I have no problem with this idea.� Hell, I’d love to see the country run with it.

Lets consider the precedent.� In 1961 the United States couldn’t send a man to orbit (embarrassingly, kinda like now).� By 1962 we had sent a man into orbit for a brief period of time and were still a couple years away from actually having spacecraft do precision manuvers, dock or stay aloft for more than a couple of days.�� In 1968, a spacecraft with three men orbited the moon and in 1969, two men landed on the moon.

Sure, today the US government takes decades to make a decidedly non-revolutionary space capsule, but it was not always that way nor does it need to be.

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The US Space Program’s Plutonium-238 Crisis

Friday, January 6th, 2012

When spacecraft are sent to explore the inner solar system, solar cells are usually the choice to provide power.� However, when venturing out past the orbit of mars, the intensity of sunlight available makes it increasingly difficult to obtain sufficient amounts of power.� Past Jupiter, it’s virtually impossible to power a space probe with solar cells as they would need to be enormous to gather enough sunlight.� Even within the inner solar system, where sunlight is reasonably intense, solar cells provide limited energy for probes that explore the surface of planets, such as the mars exploration rovers.� Sunlight is also problematic for places like the earth’s moon, where spacecraft would sit in complete darkness for days.

The solution to this problem has been the radioisotope thermal generator.� An RTG is a simple device, consisting of a strong particle-emitting isotope that produces heat and a thermoelectric generator which converts that heat into electricity.� The heat can also be used to keep vital components of the probe warm.� Unlike nuclear reactors, radioisotope thermal generators are extremely simple, have no minimum critical mass, produce little gamma and almost no neutron emissions, which could blind scientific instruments, and therefore require little or no shielding.� Modern RTG’s can provide hundreds of watts of reliable electrical power for years on end in a small, durable package.

The choice of isotope for space missions has always been, and continues to be plutonium-238. Plutonium-238 is a powerful alpha emitter which produces enormous amounts of heat energy.� Plutonium-238 produces only a small amount of low energy gamma emissions, making it easy to shield.� It’s easily prepared into ceramic oxide pellets that are chemically stable and have good thermal transfer.�� With an 88 year half-life, plutonium-238 is short lived enough to be a good energy producer yet long lived enough to allow for missions of many decades.

All radioisotope thermal generators used for deep space missions have used plutonium-238.�� RTG’s were also used to power the Apollo Lunar Surface Experiments Packages left by astronauts on the moon.��� The RTG used for the Mars Science Laboratory provides 110 watts of electricity and uses about 4.5 kilograms of plutonium-238.� Larger RTG’s have been built for deep space probes, which provide up to 300 watts of power and use 7.8 kilograms of plutonium-238.� Some spacecraft have used multiple RTG’s, for example, Cassini was equipped with three RTG’s which provided a total of 900 watts of power to the spacecraft.

There are other isotopes that can also be used to provide power for RTG’s, but none are as desirable as Pu-238.�� Strontium-90, a high energy beta emitter, which can be extracted from spent fuel, also produced significant amounts of heat, but would require substantially more shielding and produces less power per gram of material.� Isotopes of Curium have been studied as well, but also provide much less power and require greater shielding.� Americium-241 has also been considered, but at least four times as much material would be needed to produce the same amount of power, and greater shielding would also be required. Still, Am-241 is regarded as being the second most well suited fuel for RTG use.

Worldwide production of Am-241 is only a few kilograms per year, with US production capacity standing at only 500 to 750 milligrams annually.�� Most of this material is already used to fill demand for smoke detectors and moisture gauges.� In order for the US to have a viable chance of using Am-241 as an RTG fuel, production would have to be ramped up significantly.

At one time, plutonium-238 was relatively cheap and easily available.� The United States had large stocks of the material and used it for numerous space missions.� Yet since the early 1990′s, that has not been the case.� Since then, only Russia has had the capacity to produce plutonium-238 and the price has skyrocketed.�� US missions have been entirely dependent on plutonium-238 purchased from Russia at the cost of hundreds of millions of dollars.� Yet now even this limited supply is threatened, as Russia has begun to signal that it will no longer be able to provide the quantities of Pu-238 that the US (or potentially other nations) would require for continued space exploration.

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