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Here's the latest on space, and my opinions on it...
This is the legacy site, with blog entries from November, 2004 through June, 2011.
Updates after June 9, 2011 can be found at

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Saturday, March 31, 2007

Second Life on Mars?
Alan Boyle discusses space activities in the Second Life virtual world. Sounds like something really cool, if only I had the time and another need to upgrade my computer...

Right now, the action sounds pretty basic, as no real 'travel' takes place:
For now, virtual rockets that are blasted with enough force to go into orbit simply disappear once they reach a certain height, then end up being returned to the "lost and found" in Second Life. But Laughlin said there's no ironclad reason why space couldn't be simulated.
So you 'teleport' to different planets.
8:35 pm est

Subscale Injector Firings?
In the much-evolving design of the Ares V heavy-lift booster, what started as a shuttle-derived vehicle has evolved into something...else. Here are the changes that I'm aware of so far:
  • Switching away from the Space Shuttle Main Engine (SSME) for the core stage 5 engines and the upper stage. The replacement engines (the RS-68 and the J-2X) use the same propellants as the SSME, but have a lower performance overall. This drove the need to:
    • Make the solid rocket boosters longer
    • Increase the diameter of the external tank
    • "Man rate" the RS-68 engine (the J-2X will be man rated for the Ares I vehicle)

The last bullet is where things get a little sticky. There is no clear definition of "man rated," and it has typically boiled down to "whatever requirements we come up with that we can meet in the time and budget allowed." Previous arguments have said that there needs to be the addition of a killswitch option, so the crew can shut down the engines manually. Actually, all rockets have that capability, because any range destruction actions (taken if the booster goes off course) shut down the engines first and then destroy the vehicle. So the addition of a killswitch is a computer interface problem, not an engine issue.

Following the principle that work expands to fill the time allowed, there may be a drawback in the long development timeline for the Ares V. According to this article, some folks at Marshall Spaceflight Center are testing RS-68 subscale parts. Maybe they're looking to boost the performance of the engine a bit, but when you get to subscale testing, that's starting to sound more like a complete redesign of the engine. Of course, the contractor won't care if they have to stand up another production line for the RS-68-N (for NASA) while the normal line for the RS-68 continues on, but I'm not convinced that would be a wise way to proceed.
7:19 am est

Wednesday, March 28, 2007

Trying Something New
Just got an offer from Amazon to beta test context links. The idea is that when I type a phrase that happens to be related to something on sale at Amazon, there'll be a dashed line placed underneath and a click will take you there. I hope it isn't too tacky. Feedback is welcome.
3:50 am est

Tuesday, March 27, 2007

Rampant Speculation Partially Confirmed
Here is a NASASpaceflight article I just got pointed to, published the same day as this post, where SpaceX discusses their preliminary findings on their flight problems. They're basically saying that the 1st/2nd stage impact created a much higher than expected rotation rate on the 2nd stage (2.5 degrees/second) which excited a propellant slosh problem. Sounds interesting. To me it seems that the ~2 minutes of flight that looked stable through the camera would make it look like the staging impact wasn't a factor, but again they have much better data.
3:54 am est

Monday, March 26, 2007

New Essay Published in The Space Review and Locally
I've been thinking a lot lately about asteroid missions, and wanted to check recent claims about how easy their exploration will be. Based on a small survey I've done, the missions are possible, but pretty rare. I wrote it up here, and summarized it for The Space Review.

It seems to have caught some interest. More details later, maybe.

Perhaps another project will come to visibility soon.
4:15 pm est

Saturday, March 24, 2007

Am I Being Spammed, or are People Actually Reading?
I've had the "sign up for updates" email form below and to the right for quite some time. I also had a comments form at one time. I didn't hear much from them for a while, and then they exploded with spam, so I deleted the comment form. I still get a couple sign-ups for email updates per day, but I have no idea whether or not there are people at the other end of the email. I've inserted a low-grade encryption to the process, and I'd be curious how many people actually are signing up. If you agree that I'm not overwhelming you with email (I think I've sent out one email), and you don't mind, please either sign up or re-sign up entering the text from the graphic. We'll see what's going on.
4:32 pm est

Even More on Asteroids
New Scientist has an article on asteroid missions here. In it, they mentioned an asteroid as a possible destination which wasn't one that came up on my search for an upcoming article. As usual, the probelm is more complex than once thought...
1:20 pm est

Speculation runs Rampant... why not contribute?

This article talks about the fact that stage 1 of Falcon contacted the 2nd stage bell as stage 1 fell away. SpaceX confirms that here. SpaceX says that the bump didn't play a role in the later problems, and based on what I saw, I agree. If the nozzle had been deformed, it seems to me that problems would have come up earlier. One potential scenario is a very small deformation in the nozzle which leads to increased thrust vector control being needed, eventually depleting the propellants. The second article also has an interesting discussion about how their support ship has to stay outside the box where stage 1 fell. This fact contributed to their being unable to recover stage 1. The ships that recover the shuttle's solid rocket boosters are allowed within the box. It seems to me that, since the stage recovery craft is part of SpaceX's operation, they should be able to get inside, though another possibility is that, since they are essentially hired help, there are insurance issues.

I've been in email contact with a friend/reader who's worked with satellite propellant slosh issues, and they believe that the second stage footage is consistent with that kind of problem. In this scenario, the coning of the engine seen in the video builds up, and makes the propellant within the stage 'circle the drain', creating a roll force. (A similar effect takes place if you put water in a bowl and, while holding it on a flat surface, move it in a circle. Eventually, you'll get the water spinning. A more visible example is one of those 'tornado' toys where two 2 liter bottles of cola are attached nose-to-nose with water inside. When you get the spinning motion going, a vortex forms) Once that force got bigger than the roll control system could handle, things went from bad to worse.

SpaceX has been really good about sharing in their ups and downs. I'm sure that the speculation will end soon when they announce their investigation results.
5:39 am est

Thursday, March 22, 2007

A Little More Help...
The Youtube version of the SpaceX launch can be found here.  No word on the source.  The additional seconds of footage certainly show things getting worse.
6:22 am est

Wednesday, March 21, 2007

More Falcon Discussion
SpaceX has video of the launch in their gallery.  Low and high bandwidth versions available.
NASASpaceflight has a forum with lots of people discussing the flight.
Spaceflightnow has a summary of the days events including what SpaceX has said.
To me, something just doesn't add up.  It may be a lack of information on my part, due to some sort of delay between telemetry that SpaceX saw and the downlinked video, but the video only shows about 90 degrees of roll (Elon Musk says that roll was the problem in the Spaceflightnow article above) before cutting out.  If not planned for, that kind of roll isn't good, but the rate doesn't seem high enough to cause a propellant starvation problem.  The visible rate doesn't seem to have a great acceleration, either.  This is all speculation based on the video and assuming that there was no lag between the video and real life, but my thoughts are that an engine shutdown wouldn't have stopped the video.  Something more catostrophic and abrupt could have stopped the video from the source (I don't like seeing what looks like a hotspot on the 2nd stage engine bell...burnthrough?).  Another possibility is that SpaceX stopped the video once they saw things going down hill.
I remain very supportive of the effort and hope that whatever the problem is, it's easy to rectify and move on with.
Update:  The NASASpaceflight forum has a link to a Youtube video that supposedly shows more video including the roll.  I haven't been able to watch it yet.
11:47 am est

Tuesday, March 20, 2007

Congress Strikes Again
I just noticed that the blog posting times do not reflect daylight savings time. Thank you, our elected officials.
8:25 pm est

Yay!!!...Uh oh
Launched on second attempt. First stage appeared to go really well. Second stage looked good early on, but now SpaceX is reporting a loss of telemetry and the weblink went dead. Not good signs.

Based on the view I saw, there was some overcorrection going on (the 2nd stage engine nozzle started coning) and there seemed to be some spots on the second stage engine that were much hotter than other spots. That is purely based on the view from the 2nd stage camera.

The 1st/2nd stage separation seemed a little rough, with the first stage banging into the nozzle of the second stage engine. The second stage started to turn a bit, but then the engine ignited and brought it back on course.
8:23 pm est

Guess They Need an Orange Limit
According to SpaceFlightNow, the abort was caused by a low-thrust indication on the engine. Thrust was .1 percent under the red limit, and they think the low thrust was called by the kerosene being too cold.

My first thought was, "Wow, cool!" but now I'm getting more into the camp of "Why is the reading below your red limit? Did you set the limit too high? Is something different than in a previous launch attempt or engine firing?" Obviously, they have more answers than I do.

I still want to see them fly.
7:31 pm est

Well, Closer...
This time, the Falcon I engine actually ignited. They're safing things now. No word yet on the cause.

Note to SpaceX: Watch your "hot mikes." Some pretty foul language got out over the web broadcast. I'm glad my son had stopped watching.

I do look forward to the day when there's enough automation in this process that the 'countdown' goes away. The whole count from 10 seconds was actually a plot device for Frau im Mond, an early German sci-fi movie depicting a trip to the moon.

Once we're flying enough rockets, there won't be a need to create drama in buildup.

Now, they're talking about the possibility of recycling to try launching Falcon again today...interesting. Still no word on the cause of the shutdown. Maybe something has changed in the world of spaceflight already. Of course, if there's a problem, there's a whole new area to investigate.
7:19 pm est

Some High-Profile Dislike of the Report
According to Leonard David, Rusty Schweickart, of the B612 Foundation, wants to see the rest of the report so he can look into what went into the comparison of deflection methods within the report. B612 has a horse in the race because they've spent a lot of talking about the gravity tractor (on of the papers on the web page), and that option fared pretty poorly in the analysis of alternatives in the report. The way I read it, the report stated that kinetic and nuclear options had much better technological readiness levels than landing on the asteroid and pushing it or using a gravity tractor. Considering that an asteroid impact was demonstrated a couple years ago by the Deep Impact Mission, I think that statement is sound. I would like to see the rest of the report, though.
7:09 pm est

Active Mars Cratering
I'd heard that the Mars Global Surveyor spacecraft showed craters in some newer images, allowing a rough calculation of the cratering rate on Mars. Cratering rate is a big deal for measuring the age of a feature (count the number of craters on it, multiply by the rate, and you get an estimate of how old it is). I hadn't read the background of the research. Here is the page talking about it.
6:51 pm est

Trying Again...
I've got SpaceX's second launch attempt up on webcast. Good luck, SpaceX!
6:46 pm est

Monday, March 19, 2007

So Close...
I just got my web broadcast up in time to see the abort. Hope it's nothing serious.
6:47 pm est

Sunday, March 18, 2007

Fly, Falcon!?
SpaceX just sent out an update saying that they're shooting to launch this week. One glitch with their backup GPS guidance system after the static firing may push things later in the week. Elon took a moment to address concerns over whether there'll be another one-year delay if there's a problem with this flight:
I know it has been a year since our last launch and some people are wondering if launch 3 will also be a year away if something goes wrong this time. The answer is definitely no. The reason it took us a year is that the vehicle on the pad and the ground support equipment have hundreds of robustness upgrades -- this is really Falcon 1 version 2.

There is nothing significant that we can think of to improve the vehicles under construction for the Dept of Defense and Malaysian satellite launches later this year. Therefore, no matter what happens, I do not expect there to be a significant delay in their approximate end of summer and mid fall launch dates.
Video of the static firing can be found in two forms, medium, and closeup. I want to see this rocket fly, well. The recent web page upgrades they made don't matter much until a rocket they build flies.
5:48 am est

STEREO Ramping Up
Reported earlier on an awesome transit viewed by one of the STEREO craft. A few days ago, The Washington Post talked about the mission. 3-D images expected in May or June!
5:37 am est

Saturday, March 17, 2007

Big News on Mars
Announced at the Lunar and Planetary Science Conference, two big items:
  • Caves on Mars.  Surface features that heat through the day and cool at night just like caves would.  Can't wait to see some high resolution images of them!
  • LOTS of ice on Mars.  Europe's Mars Express has been radar mapping the poles of Mars for a while.  Results were released about the South Pole.

Both good news, though kind of expected by most of us who follow the stuff.

8:39 pm est

Friday, March 16, 2007

One Vision of the Future of Space
Mike Griffin, NASA Administrator, has an article where he tries to imagine what we can do in the next 50 years in space, assuming relatively stable funding.  I enjoyed the read.  Especially this fact:
From a decadal viewpoint, the “Apollo peak” in NASA funding, regarded by so many as the agency’s halcyon period, is a myth.  In truth, NASA received funding well above its historical average level for only five years, 1964-68, followed by a lengthy and debilitating reduction.  But when averaged over decadal or fifteen-year time scales, the nation’s civil space program has experienced no particularly noteworthy funding peaks.  The highest historical funding period was actually in the decade (or 15-year interval) centered on the early 1990s, not during Apollo.
I may have more to say later.
6:37 pm est

Commercial Orbital Propellant Depot?
Here is an very exciting article about a company that wants to put a propellant depot in Earth orbit.  While excited, I will stay in the 'skeptical' column until I see some action on the part of the company in question.  One part of the plan which is probably drawing a lot of interest is the idea of filling the depot using hydrogen and oxygen from the moon.  That makes the plan quite ambitious.  I have no doubt that, given sufficient demand (and proven supplies of hydrogen and oxygen on the moon), that source may be best.  In the short term, however, a better proof of concept may be the use of supplies launched from Earth.
My logic goes like this:  The proposed budget is $15B with an estimated "open for business" date of 2015.  That is on the order of 15% of NASA's released cost for returning people to the moon on a shorter schedule.  In order to make such a low number possible, there will have to be significant use of low-cost launch on the order of SpaceX (who've updated their web page with some new info, and are scheduled for another launch attempt as well).  Given the lower cost of launch, a much lower risk and lower cost initial demo could be accomplished simply with Earth-based launchers.
More discussion here and here.
The paper the idea is based on can be found, along with an...extensive resume on the author here.  (Acrobat required)
3:16 pm est

Tuesday, March 13, 2007

Space Technology...Mandatory for Climbers?
Apparently, the Oregon Legislature is thinking of making rescue beacons mandatory for climbing Mt. Hood. The article doesn't mention that the beacons use satellites to determine the stranded person's location.
4:29 pm est

Monday, March 12, 2007

***Earlier Announcement Retracted***
Turns out, the information previously posted here was not for public release yet. I will post when it is clear.
5:46 pm est

Sunday, March 11, 2007

The statement in the asteroid threat report that I commented on earlier, which caught my eye as being hard to believe that current or envisioned launch vehicles couldn't reach 30-80% of the potentially hazardous NEOs was just oversimplified in the executive summary. The report describes several options for deflection, and says that for most of the options examined, deflection isn't possible in a single launch using launchers in existence today or planned for the near future. The launchers they considered were the Delta IV Heavy and the Ares V.

Update at 9 PM: Charts in question can be found here. I included the explanatory text, because they take a little digesting.

Update at 5 AM: The more I think about it, given the energies involved, I'm surprised that any launch vehicle in our "quiver" can achieve any of these missions. Of course, the "easiest" one chosen is moving Apophis 5km by the time it reaches its 2029 close approach. The next one up in energy requires moving it by the radius of the Earth in a similar timeframe...
2:45 pm est

Asteroid Threat Report Summary Hits the Streets
NASA was required to submit a report to Congress on Near Earth Object (NEO) threats to Earth and mitigation strategies.  The summary is now out.  I'm going to read it today (hopefully) but for now, I'm focused on the following finding:
30-80 percent of potentially hazardous NEOs are in orbits that are beyond the capability of current or planned launch systems. Therefore, planetary gravity assist swingby trajectories or on-orbit assembly of modular propulsion systems may be needed to augment launch vehicle performance, if these objects need to be deflected.
My hope is that the statement is just simplified too much.  For one thing, a 30-80 percent range?  That's pretty wild.
7:47 am est

New Martian Dust Study
Most reports on Martian dust relate to what "may be there" chemicals that, though they were not tested for on the Viking missions, may be present and therefore "need to be investigated" before sending people there. For this article, researchers actually created a Mars soil simulant and ground it into very fine grains estimated to be the size found on Mars. They took the new dust grains and exposed them to water to see what the effects were. The effects were not good. They describe the dust as being more reactive than quartz dust, which causes silicosis in mine workers.

I agree that the Mars dust is probably worse than dust quartz miners are exposed to. I believe that the comparison of people who work in mines in a cloud of dust all the time (likely, the miners wear breathing apparatus now that the dangers of silicosis have been fact the Wikipedia article cited above for silicosis backs that up) and those who work on Mars' surface in a pressurized suit is overdrawn. People exposed to a small amount of dust due to bringing some in on their suit seems different to me. There is the issue of the dust getting into the ventilation system and blowing around the habitat, but there still seems to be some link missing in the comparison. I may have more coherent thoughts on this issue later.
6:54 am est

Asteroid Threat Wrapup
I gotta hand it to the asteroid threat guys that met in Washington this past week. They appear to understand the concept of 'media blitz,' though their implementation is a bit off. Three new articles are out, though only one is in a mainstream newspaper. Here's the list:
  • The Washington Post covers the idea that planet killer asteroids aren't the ones to worry about, it's the smaller ones.
  • Louis Friedman gives members of The Planetary Society an overview of what happened.
  • New Scientist discusses a new (to me) idea of placing a dedicated asteroid-searching telescope at the Sun/Venus L4 or L5 point.

In other news, doubts are rising about a 'meteorite' that struck an illinois home. Looks like it may have been woodchipper debris.  Hats off to some commenters on The Bad Astronomer entry on the event who called out some of the same issues with the pictured meteorite now being called into question by the experts.
6:33 am est

Saturday, March 10, 2007

Spinning Space Rocks
A great article here about the recently-proven fact that asteroids change their rotation rate over time. The effect makes sense, given that the Yarkovsky effect has been documented, and Yarkovsky is actually one of the names included in the quadranym acronym YORP. What stood out for me is that there's an asteroid (2000 PH5) out there that spins once every 12.17 minutes! Apparently, that asteroid is pretty solid, because according to my calculations and assuming that the rock spins around its center, I calculate an acceleration of .05 m/sec2. That's about 170x less than Earth gravity, but it's likely enough to pull apart an asteroid that's a 'rubble pile'. It's likely that 2000 PH5 is a solid piece of rock or iron, which is an interesting point of its own. Of course, the fact that it's spinning so fast isn't news. The discovery is that the rotation rate is accelerating, with the "day" of the rock shortening by 1 milisecond every year. The other asteroid reported on in the story, 1862 Apollo, is accelerating even faster.

One interesting point: Asteroids that are spinning too fast will be difficult to land on, because the rapid spin would throw a spacecraft off the surface.
3:11 pm est

(Some) Details Coming to Light on Discovery Channel Mars Event this Fall
Here is an article detailing some of the plans The Discovery Channel has for their Mars mini-series this fall. They show some promise. A couple highlights:
The two programs will fuel a fall programming strategy that aims to draw viewers in with drama, interaction and speculation about a manned trip to the red planet in 2030. Discovery president/GM Paul Lewis promises the Mars initiative "will be one of the biggest factually-based programming events ever."
"It's going to be very highly integrated with the production, with lots of features such as games and information," she adds. "It's also going to be devised so that it's appropriate for different age groups. There will be more than one target demographic, because what we're trying to do with the Mars initiative is really capture the imaginations of people throughout Canada, regardless of age."
I expect that this amount of work will be distributed to the US, not only shown in Canada!
6:39 am est

Friday, March 9, 2007

Useful Time in the New Mexico Legislature
There once was a time when this sort of thing would make me angry as a waste of time.  The New Mexico Legislature has declared that Pluto is a planet.  Nowadays, while I understand that it didn't take a lot of time, I'm just glad that they weren't spending time passing laws that make things more complicated in real life.
6:30 pm est

Wednesday, March 7, 2007

Earth as Art
If you haven't seen this collection of Landsat images, you're missing out. They can be downloaded in large format for free.
6:44 pm est

Latest Status on Lisa Nowak
A short statement from NASA reguarding her status can be found here.
6:28 pm est

I had High Hopes
I was poking around the Ares page today, when I came across this feature. A few months old, to be sure, it talks about how building a new rocket really is ROCKET SCIENCE. Within the feature is Rocket Science 101, an interactive game to let you assemble your own rocket. I guess I exected too much, looking for mass tradeoffs of 4- vs 5-segment solid boosters, the varying sizes of 2nd stages, and any accompanying trades in the escape system and crew g-forces. Instead, the activity has you drag pieces of a rocket together to complete a cutaway drawing. Pretty cool, and I guess it's 101-level stuff. I guess my idea would be more of a Rocket Science 415 or a graduate level course.
6:24 pm est

Monday, March 5, 2007

Nice Piece, Just Wish he Hadn't Poo-Pooed Mars
I've read Charles Krauthammer before.  He's proposed crazy ideas like supply and demand being the cause of recent spikes in gas prices.  Now, he's put together some reasons why going to the moon makes sense.  I like his reasoning...that we do lots of things without immediate return, and many things we do using public funds bring returns we don't forsee.  I disagree with him on the last two sentences of his Mars slant, however:
Sure, Mars would be better. It holds open the possibility of life and might even have water on its surface today. But the best should not be the enemy of the good. Mars is simply too far, too dangerous, too difficult, too expensive. We won't go there for a hundred years.
We could absolutely choose not to go to Mars for 100 years.  Or we could choose to go to the moon for practice, then move beyond.  In the past, that decision was purely politicial, and given current political climes, such a decision to accelerate our journey to Mars is unlikely.  I'm hoping that, with the changing space economy, there will be other drivers, keeping the best from being the enemy of the good.
7:38 am est

Global Warming, on Mars
Another crazy, petrolium-funded, agenda pushing organization is saying that Earth's global warming may not be solely human caused.  The source?  National Geographic.  The piece points out that the opinion of the Russian scientist is at odds with the majority opinion, but most changes in scientific thought are at one time or another.
I have seen presentations showing that the Earth's icecaps are smaller now than they were just a few years ago.  I believe it's possible that the Earth is warming and humans are partially to blame.  I drive a hybrid car, think SUVs are stupid status symbols, think we should wean ourselves off of fossil fuels for a myriad of reasons, and I fear for the legacy we're leaving our (my) children...but I fear knee-jerk, politico-popular fearmongering and its likely resultant legislation even more.
7:22 am est

Missed it!
Clouds blocked my view of the lunar eclipse on Saturday.  Apparently, it was quite a show.
7:10 am est

Friday, March 2, 2007

Your Planet, in Lights
I just saw a presentation on the Mars Phoenix mission to Mars' North Pole. Scheduled to launch in August, it should touch down in May of 2008. This image has me particularly excited. In it, there's a camera mounted on the robotic arm surrounded by a bunch of light emitting diodes (LEDs). The LEDs will bathe the area in question in various wavelengths of light to highlight different compounds.

One of my early, notional (read: never left my laptop), Pathfinder-class Mars missions involved ejecting capsules containing different types of acids onto nearby rocks, then taking pictures of the gases released in different strobe-lit wavelengths. Crude, and I don't know how well it would have worked, but it would have been relatively cheap.
9:53 pm est

Not the Earth-based mass- type, but the celestial music-of-the-spheres variety. We puny Earthlings have two spacecraft out there called STEREO. Their mission is to take 3-D images of the sun. One of them just took a series pictures of the moon as it crossed the solar disk. The Bad Astronomer has more, with necessary awe included.
9:33 pm est

What happens when a powerful volcano erupts on a moon with very low gravity? This.

I can't wait to see the rest of the images from New Horizons' Jupiter encounter as they're shipped back.
9:17 pm est

Thursday, March 1, 2007

The Delays Begin
Mike Griffin broke the news to Congress recently that the first flight of the Orion spacecraft will be delayed by a few months due to Congressionally-mandated cuts to budget.
I found it funny that the CNN anchor reporting the news this moring pronounced Orion as ORE-ee-yon.  Ugh.
9:13 pm est

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