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If you don't love your country as it is, then maybe you should leave.
There are plenty of bullyboy juntas out there who'll "believe in War" with you. As long as you can land a position where you can dribble out dolce et decorum est shit all day long and never actually have to murder someone, you'll have a grand ol' time.
( By the way, capitalizing "war" as if it were a god is a seriously psychotic thing to do. You should see a doctor. The life you save may be your own. )
Wikipedia has an excellent article detailing lots of possibilities ...
http://en.wikipedia.org/wiki/Fermi_Paradox
I also think that Landis' article applying insights from Percolation Theory is worth a read by itself ...
"We've never seen anything like it on any other planet," says atmospheric scientist Kevin Baines of the Jet Propulsion Laboratory. It is a hexagon twice as wide as Earth encircling Saturn's north pole.
I wondered if anything like it had been seen in fluid dynamics before, and the answer appears to be: not until recently ...
Polygons on a Rotating Fluid Surface
http://arxiv.org/PS_cache/physics/pdf/0511/0511251.pdf
Includes pretty pictures and a fun graph showing how the number of sides of the polygon depends on the rotational speed of the generator and its depth beneath the fluid surface.
More from Musk saying pretty much the same thing as the nasaspaceflight article (reduce shutdown transient for 1st stage, add baffles to LOX tanks of 2nd stage). Apparently they recovered telemetry through t+10:00.
...
This confirms the end of the test phase for Falcon 1 and the beginning of the operational phase. The next Falcon 1 flight will carry the TacSat 1 satellite for the US Navy, with a launch window that begins in September, followed by Razaksat for the Malaysian Space Agency in November.
...
I will be posting another DemoFlight 2 post launch update within a week, which will include a list of all subsystems color coded for status: green = good, yellow = cause for concern, red = flight failure if unchanged, black = untested. Of the hundreds of subsystems on the rocket, only the 2nd stage LOX tank slosh baffles are clearly red right now, but that could change with further analysis. As much as is reasonably possible (subject to ITAR and proprietary info), SpaceX will provide full disclosure with respect to the findings of the mission review team.
...
http://www.nasaspaceflight.com/content/?cid=5056
(I double checked the date this time)
Elon Musk says ...
'In a nutshell, the data appears to show that the increasing oscillation of the second stage was due to the slosh frequency in the LOX tank coupling with the thrust vector control system,' added Musk.
'Our simulations prior to flight had led us to believe that the control system would be able to damp out slosh, however we had not accounted for the perturbations of an impact on the stage during separation, followed by a hard slew to get back on track.'
While the impact observed during separation failed to damage the second stage engine's nozzle, the cause is currently being blamed on the vehicle's rotation being fives times higher than the expected maximum.
...
we believe that the slosh issue can be dealt with easily by adding more baffles, particularly in the LOX tank. The Merlin shutdown transient can be addressed by initiating shutdown at a much lower G level, albeit at some risk to engine reusability.
Oops, sorry. I'm an idiot.
Who is David Palmer
I only know him as a poster of non-bullshit to usenet. Such people are incredibly rare, so they are easy to keep track of. He has a PhD from Caltech and spent a number of years at Goddard, so it is plausible for him to be in contact with one of the teams doing the actual analysis. Still just rumor though, obviously.
David M. Palmer @ sci.space.policy says ...
It was a fuel leak around the top of the main engine, which burned
through some helium pneumatic lines. The rocket was running straight
and true until t+29 when the helium tank pressure dropped enough that
the safety system terminated the flight.
http://www.junkscience.com/draft_AR4/Ch … _FINAL.pdf
IPCC says ...
Using the "we're doomed" HadCM3 model and under a "we burn all the oil" (4xCO2) scenario, it takes 1000 years for Greenland to lose 50% of its ice volume and 3000 years to be reduced to 4%, with a peak contribution of ~ 5 mm/yr to sea level.
See also Figure 10.7.7 ...
http://www.junkscience.com/draft_AR4/Ch … NAL_P5.pdf
As a reality check, recent measurements dated one (admittedly deep) layer of Greenland ice to 110,000 years old. Antarctic ice is much older. Any real specialist in this field will tell you that both Antarctic and Greenland ice sheets are currently responding to the +8C temperature increase from the last glacial maximum 20,000 years ago. The alarmist scenarios are funding devices, pure and simple.
http://www.spaceflightnow.com/falcon/f2/status.html
Elon Musk says ...
Question: What was the debris seen floating away from the second stage engine?
"What you might have seen was basically titanium half-hoops that are used to stabilize the nozzle on ascent. However, once you get to a certain temperature the bonding agent for those titanium rings comes off and the titanium rings float away, which occurred as expected."
Let's have a look at the "consensus" on melting ice sheets ...
http://www.junkscience.com/draft_AR4/Ch … _FINAL.pdf
there will not be substantial ablation [melting] in Antarctica, all studies for the 21st century find that Antarctic SMB changes contribute negatively to sea level, owing to increasing accumulation [of snow]
I'll just reemphasize that: all studies find that Antarctica will grow, not melt, through at least 2100.
The only other important contributer to sea level is Greenland. Table 10.6.1 shows the results of 7 studies. 5 of the studies show a tiny contribution (~ 0.02 mm yr-1 K-1). One, with a non-standard climate model that de-emphasizes precipitation increase due to rising temperatures, finds a larger contribution (~ 0.10 mm yr-1 K-1). One, with a very high resolution grid (100 times the others) finds a negative contribution (~ -0.10 mm yr-1 K-1).
So, small, totally swamped by Antarctica, and possibly negative.
But what's the uncertainty in these estimates? How much do we really know?
Computing ice-sheet surface mass balance using four high-resolution AGCM simulations with the scaling technique of Huybrechts et al. (2004), see Section 10.6.4.1, indicates systematic uncertainties of ±60% for Greenland and ±40% for Antarctica
...
We include a further uncertainty of 20% of the Greenland ablation [melting] to allow for uncertainty in the parametrisation (Church et al., 2001).
I suggest that at these levels of uncertainty, the only fair use for these estimates is to rule out alarmist claims that the ocean will rise by 70 meters.
Why does commercial media trumpet alarmist claims and ignore the little that we actually know? At least there is no uncertainty in the answer to that question.
http://spacex.com/video_gallery.php
You can see the "roll excitation" in the last 30 seconds of the "Falcon 1 DemoFlight 2 Launch" video.
Elon Musk says ...
...
We retired almost all of the significant development risk items, in particular:
- 1st stage ascent past max dynamic pressure
- avionics operation in vacuum and under radiation
- stage separation
- 2nd stage ignition
- fairing separation
- 2nd stage nozzle/chamber at steady state temp in vacuum
Falcon flew far beyond the "edge" of space, typically thought of as around 60 miles. Our altitude was approximately 200 miles, which is just 50 miles below the International Space Station. The second stage didn't achieve full orbital velocity, due to a roll excitation late in the burn, but that should be a comparatively easy fix once we examine the flight data. Since it is impossible to ground test the second stage under the same conditions it would see in spaceflight, this anomaly was also something that would have been very hard to determine without a test launch.
All in all, this test has flight proven 95+ percent of the Falcon 1 systems, which bodes really well for our upcoming flights of Falcon 1 and Falcon 9, which uses similar hardware. We do not expect any significant delay in the upcoming flights at this point. The Dept of Defense satellite launch is currently scheduled for late Summer and the Malaysian satellite for the Fall.
...
Your ISP doesn't provide a reverse DNS entry for your IP address. That's fairly rare nowadays. The Imaginova webservers might be configured to require it for some reason. If you don't have the same problem when using a different ISP (say dialup instead of broadband) then that might be it.
If you use Internet Explorer, you could try clearing the various "temporary files" and cookie caches. That seems to fix a lot of odd IE problems. If you don't have the same problem with, say Firefox, then that might be it.
Otherwise try
tracert 207.73.219.100
from the command line (on Windows - probably traceroute if you have a Mac) to see if you have a path to www.space.com. If you don't, then more than likely your ISP has been blocked for being the source of a hacker/spam/denial attack at some time in the past. Ask them to get it cleared.
http://www.reuters.com/article/scienceN … 5220070321
Reuters says ...
About five minutes into the flight, a problem cropped up with the booster's second-stage engine, which shut down early due to an unexpected roll, said Space Exploration Technologies chief Elon Musk.
"We feel that is something straightforward to fix," Musk told reporters in a conference call after the flight. "It's definitely a good day."
The rocket's second stage likely re-entered the atmosphere after less than one orbit of Earth, Musk added.
The underlying report on which the IPCC summary claims to be based has been published here ...
http://www.junkscience.com/draft_AR4/
Also note in table SPM-1 that the errors in the rise in sea level from the contribution of the Antarctic ice sheet and for the Greenland ice sheet (1961 – 2003) are greater than the estimated values. This is an an indication of the state of scientific knowledge of the subject.
Bingo.
No kidding. God only knows what "victory" is supposed to look like in Iraq right now. As far as I can tell, the US is actively assisting the installation of an Islamic Theocracy with religious ties to Iran. Why are they doing that?
But the Iraq mess is nothing compared to the planned attack on Iran. Iraq has merely bankrupted the nation. An attack on Iran has a serious chance of triggering World War III. This is beyond folly. You have to question the sanity of someone who wants that.
And it is all so silly. You don't defeat religious fundamentalists by attacking them with guns and bombs. That just makes them stronger. You defeat them with MTV, Desperate Housewives and 137 flavors of liquor. Want better treatment of women? Set up a University with a Women's Studies Department. The patriarchy will wither like flowers in winter.
That's the really sad thing. The US had already won. Just a few spastic death throes from extremists and Mickie Ds would have started sprouting like mushrooms. Now Bush's mishandling of the situation has brought us to the brink of world war. It is unbelievable how much damage he has done in such a short amount of time.
Maybe, just maybe, Congress can stop us from going over the edge. Let's hope it isn't too late.
Located this reference while searching for other stuff.
Assessment of NASA's Mars Architecture 2007-2016
Of course the document link is dead...
Executive Summary ...
From http://www.nap.edu/execsumm_pdf/11717.pdf
This assessment by the ad hoc Committee to Review the Next Decade Mars Architecture was conducted at the
request of Dr. Mary Cleave, NASA’s Associate Administrator for the Science Mission Directorate, who asked
the National Research Council (NRC) to address the following three questions:
1. Is the Mars architecture reflective of the strategies, priorities, and guidelines put forward by the National
Research Council’s solar system exploration decadal survey and related science strategies and NASA
plans?
2. Does the revised Mars architecture address the goals of NASA’s Mars Exploration Program and optimize
the science return, given the current fiscal posture of the program?
3. Does the Mars architecture represent a reasonably balanced mission portfolio?
It is important to note that the original order of the questions posed by Dr. Cleave was 2, 3, and 1. That is, the
one that now appears first was originally listed as last. The committee has taken the liberty of reordering
the questions because it is strongly of the opinion that logic dictates that it start its assessment of the Mars
architecture by first addressing the architecture’s scientific foundations.
Following presentations, discussions, and deliberations, the committee developed the following findings and
offers specific recommendations relating to each:
1. Is the Mars architecture reflective of the strategies, priorities, and guidelines put forward by the NRC’s
solar system exploration decadal survey and related science strategies and NASA plans?
The committee finds that the proposed Mars architecture addresses some of the strategies, priorities, and guidelines promoted
by the solar system exploration (SSE) decadal survey and the Mars Exploration Program Analysis Group
(MEPAG) and is basically consistent with NASA’s plans as exemplified by the agency’s 2006 strategic plan1
and the Vision for Space Exploration.2 However, the absence of a sample return mission and a geophysical/
meteorological network mission runs counter to the recommendations of the SSE decadal survey and
significantly reduces the architecture’s scientific impact. Other topics of concern include the lack of welldefined
mission parameters and scientific objectives for the Mars Science and Telecommunications Orbiter,
Astrobiology Field Laboratory, and Mid Rover missions; issues relating to the phasing and responsiveness
of these missions to the results obtained from past missions; and the incompletely articulated links between
these missions and the priorities enunciated by the SSE decadal survey and MEPAG.
The committee offers the following recommendations to NASA:
• Recommendation: Include the Mars Long-Lived Lander Network in the mix of options for the 2016
launch opportunity.
• Recommendation: Consider delaying the launch of the Astrobiology Field Laboratory until 2018 to
permit an informed decision of its merits and the selection of an appropriate instrument complement
in the context of a mature consideration of the results from the Mars Science Laboratory and other
prior missions.
• Recommendation: Establish science and technology definition teams for the Astrobiology Field
Laboratory, the Mars Science and Telecommunications Orbiter, the Mid Rovers, and the Mars
Long-Lived Lander Network as soon as possible to optimize science and mission design in concert
with each other. (This model has been employed successfully by the heliospheric community.)
• Recommendation: Devise a strategy to implement the Mars Sample Return mission, and ensure that
a program is started at the earliest possible opportunity to develop the technology necessary to
enable this mission.
2. Does the revised Mars architecture address the goals of NASA’s Mars Exploration Program and optimize
the science return, given the current fiscal posture of the program?
The committee finds that it cannot definitively say whether or not the revised Mars architecture addresses the goals of NASA’s Mars Exploration
Program because the architecture lacks sufficient detail with respect to the science and the cost to allow a
complete evaluation. The various mission options are, as stated above, incompletely defined, and the strategic
approach to, and the selection criteria to distinguish among, various mission options are lacking. The
presence of Mars Scout missions in the architecture is welcomed because they help to optimize the science
return and provide balance. Nevertheless, the Mars architecture as a whole is not optimized, because the
importance of foundational strategic elements—for example, research and analysis programs and technology
development—is not articulated.
In response to this finding, the committee offers the following recommendations to NASA:
• Recommendation: Develop and articulate criteria for distinguishing between the three options for
missions to launch in 2016. Similarly, define a strategy that addresses the short lead time between
science results obtained from the Mars Science Laboratory and selection of the mission to fly in 2016.
• Recommendation: Clarify how trade-offs involving mission costs versus science were made for the
various launch opportunities to justify the rationale behind the proposed sequence of specific missions
and the exclusion of others.
• Recommendation: Maintain the Mars Scouts as entities distinct from the core missions of the Mars
Exploration Program. Scout missions should not be restricted by the planning for core missions, and
the core missions should not depend on selecting particular types of Scout missions.
• Recommendation: Immediately initiate appropriate technology development activities to support all
of the missions considered for the period 2013-2016 and to support the Mars Sample Return mission
as soon as possible thereafter.
• Recommendation: Ensure a vigorous research and analysis (R&A) program to maintain the scientific
and technical infrastructure and expertise necessary to implement the Mars architecture, and
encourage collaboration on international missions.
3. Does the Mars architecture represent a reasonably balanced mission portfolio?
The committee finds that in the context of the basic types of missions, the Mars architecture is a reasonably well balanced one: both
landed and orbital missions are included in an appropriate mix, given the current state of Mars exploration.
To the extent that the specific science objectives of the proposed missions are defined, one of the three
crosscutting themes for the exploration of Mars identified in the SSE decadal survey is largely neglected, as
are very high priority topics related to understanding near-surface and boundary-layer atmospheric
sciences, and so, in this respect, balance is sorely lacking.
To optimize efforts to implement a balanced portfolio of missions, the committee offers the following recommendations
to NASA:
• Recommendation: Include the Mars Long-Lived Lander Network in the mix of options for the 2016
launch opportunity.
• Recommendation: If the Mars Long-Lived Lander Network cannot be implemented in the period
under consideration, provide for an effort to make some of the highest-priority measurements on the
landed missions that are included in the proposed Mars architecture.
• Recommendation: Ensure that the primary role of the Mars Science and Telecommunications Orbiter
is to address science questions, and not simply to serve as a telecommunications relay. This distinction
is particularly important with respect to the required orbital parameters that are adopted.
a window of vulnerability until it is rotated out.
what do you mean by this? i would just assume that it would go dead and stop producing soo much heat.. or does it mean that the fuel is used up and massive amounts of radioactivity occur inside the pebble?
The pebbles are layered like an onion, with each layer serving a purpose, and the outer layers actually forming part of the containment system of the reactor. One of the inner layers is graphite and some of the outer layers are ceramic. If the ceramic cracks and exposes the graphite then there is a scenario where the graphite could burn and leak radioactive particles into the environment. The scenario is unlikely - the inert cooling gas would have to be contaminated with air, and the operating temperature would have to double somehow - but safety standards for nuclear reactors are so high, that everything becomes a concern.
what is the down side to the pebbles
The only serious criticism I've seen is that the pebbles are a possible point of failure. There are a zillion of them in each reactor, so eventually one of them will fail, creating a window of vulnerability until it is rotated out.
It's still hypersafe compared to everything else out there, and eliminates the real threat of dual-use technology proliferation.
I guess from the poll above, the majority of people by a margin of 2 to 1 don't think the United States needs a President to run the Armed forces.
The Whitehouse has spent US blood and treasure to no good end. The situation would be better if Bush had spent his entire presidency holidaying at his ranch, and the nation would be hundreds of billions of dollars, not to mention thousands of lives, richer. Congress should do whatever they can to limit what further damage Bush & Company can do to the nation. Godspeed to them.
Perhaps consider potassium superoxide (KO2) which produces oxygen as it scrubs carbon dioxide. Of course, it will only save you mass if you were going to carry something else to make oxygen.
Instead of using the login button at the top,
try using the login panel at the bottom of
You seemed to have logged in to post the above post.
What is it about the login system that isn't working?
The difference with traditional agnosticism here is that it allows for the possibility of truth, whether known, unknown, or intrinsically unknowable.
The problem is that truth is traditionally conceived of as true for everyone. Perhaps your followers could be post-modern agnostics giving up universal truth and always qualifying with "true for me" and "true for you" while maintaining that gnawing sense of uncertainty that prompts them to plan for cryogenic suspension instead of burial.