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#3052 Re: Science, Technology, and Astronomy » Reverse propagation of light? » 2006-05-12 01:51:33
A very curious experimental result .. anyone understand this?
Boyd, along with Rochester graduate students George M. Gehring and Aaron Schweinsberg, and undergraduates Christopher Barsi of Manhattan College and Natalie Kostinski of the University of Michigan, sent a burst of laser light through an optical fiber that had been laced with the element erbium. As the pulse exited the laser, it was split into two. One pulse went into the erbium fiber and the second traveled along undisturbed as a reference. The peak of the pulse emerged from the other end of the fiber before the peak entered the front of the fiber, and well ahead of the peak of the reference pulse.
#3053 Re: Unmanned probes » Gaia - ESA billion star survey satellite » 2006-05-11 13:45:16
Contract given to EADS for construction
Paris, 11 May 2006 – EADS Astrium has signed a contract with the European Space Agency (ESA) to develop and build the satellite for the Global Astrometric Interferometer for Astrophysics (Gaia) mission. Gaia will create an extraordinarily precise 3-D map of the Galaxy, mapping and recording more than one billion stars over a five year period. The satellite, worth €317 million, is due to be launched in 2011.
#3054 Re: Unmanned probes » Venus Express - ESA orbiter » 2006-05-09 14:44:02
ESA says that VEX is now in its final operational orbit .
No mention of a problem with the instrument mirror.
As of the 9-day capture orbit, Venus Express had to perform a series of further manoeuvres to gradually reduce the apocentre and the pericentre altitudes over the planet. This was achieved by means of the spacecraft main engine – which had to be fired twice during this period (on 20 and 23 April 2006) - and through the banks of Venus Express’ thrusters – ignited five times
#3055 Re: Human missions » Do you (exactly) know how to "man-rate" a rocket? » 2006-05-09 10:31:13
Lets try to keep the acronyms straight in that the CLV/CEV is DaStick or what may be named Ares I with its CSM, while the CaLV cargo launch vehicle is possibly Ares V. The CaLV is an unmanned ship until joined to the CEV in orbit. The Calv will have the LSAM (Artemis)and EDS.
Good idea. According to the ESAS the CLV, also known as The Stick, will launch the combined CEV/SM to LEO. The CaLV, aka HLV and SDLV, will also lift the EDS and LSAM to LEO. The CEV/SM then docks with the EDS/LSAM and the EDS then moves the whole kaboodle to lunar orbit. Piece of cake.
AFAIK NASA has not used the names Ares I or Ares V. I propose calling the CaLV 'The Griffin' as he's doing all the heavy lifting right now :>
#3056 Re: Interplanetary transportation » Ares I (CLV) - status » 2006-05-09 06:00:00
The initial target weight value was put within the capability to fly on modified versions of delta and atlas but Griffin wanted to get away from the man rated issue and bumped the weight out of there capabilities. I think about late 2004.
(aka the "60 Day Study")
There was no initial target weight. These are all working estimates that were derived during the ESAS started by Griffin when he took over in 2005 and finished during that summer. There is no detailed breakdown of the 25 mt yet, no doubt even that number will change as the design evolves. NASA's unique experience with manned lunar space vehicles makes their numbers better than anyones. RTTM is hard. To do it with four crew and to do it well, safely and in a sustainable way, needs a capable vehicle and that means heavy.
#3057 Re: Interplanetary transportation » Orion (CEV / SM) - status » 2006-05-09 02:29:20
To boldly go where no thread has gone before ...
Some good news for those of us who like the idea of a Mars ready LOX / CH4 engine for the CEV SM
Minneapolis, May 8, 2006
Alliant Techsystems (NYSE: ATK) has received a $10.4M technology development contract to reduce the risk to develop a non-toxic Liquid Oxygen (LOx)-Liquid Methane rocket engine that could be used on future Crew Exploration Vehicles (CEV).
#3058 Re: Human missions » Alt.space debacle (GCNRevenger 's gonna love this) » 2006-05-04 14:37:56
Have never heard of the Denarius IV spacecraft or of its unmanned monetary-ejection program to study the effect of a hard-vacuum, zero-gravity environment on $50 and $100 bills.
It was a follow on program to the successful use of $10 bills as propellant additives for the STS propulsion system.
#3059 Re: Interplanetary transportation » Ares V (CaLV) - status » 2006-05-04 14:29:29
Here is a nice link:
http://www.ilr.tu-berlin.de/koelle/ILR- … ILR351.pdf
Yep a very detailed history of the Saturn V, thanks.
The www.avia.ru english newsbrief had the following news on the RD-171M
For those of us who only know that the RD series are rockets engines, what is the significance of that newsbrief?
This story has come and thankfully gone, in fact it was removed from the database a few days ago, yet another example of crappy journalism (New Scientist also had the scare story) more interested in making a splash (haha) than getting the facts right.
#3060 Re: Interplanetary transportation » Ares I (CLV) - status » 2006-05-04 10:55:41
It would appear with some other searches that there is a little confusion on the number of segments for the calv was intended to have dual 5 segments but when the cev weight was increased it lead to the CLV also requiring it as well..
The CaLV was specified with 2x5 segment SRBs in the ESAS. The CLV initially had a 1x4-segment first stage that was later changed to a 1x5-segment with PBAN propellant (slightly higher ISP).
When was the CEV weight increased? AFAIK no weight as been formally specified. In fact as the diameter has now been changed from 5.5 to 5.0 metres this would surely reduce the weight. A round number of 25 mt has been given for payload capacity of the CLV, this hopefully will be less than the weight of fully fueled SM and CEV.
#3062 Re: Unmanned probes » SMART-1 - ESA lunar orbiter » 2006-05-03 13:13:59
Smart-1 studying Hopmann crater
Smart-1 is studying the far side crater Hopmann but is also using calculated thrists to ensure its collision with the Moon in september.
SMART-1 doesn't have to do anything to ensure that, gravity will take care of it 
ESA are trying to lower the orbit as near to the surface as possible to maximise data collection. They are trying for an orbit just 100 metres above the peaks, should be quite a ride,
#3063 Re: Interplanetary transportation » Ares I (CLV) - status » 2006-05-03 13:04:50
I started looking at some of the old stage info from
this chart and they are missing the details of the CEV engine.
They also seem to be off with regards to the burn times...
Yes and of course those charts do not include the current CLV configuration - the 5-segment PBAN SRB first stage and the J-2X LOX/LH2 upperstage
#3064 Re: Human missions » Hang-gliding to orbit? » 2006-05-03 12:58:50
#3065 Re: Human missions » Spacesuits - personal spaceship » 2006-05-02 13:09:04
Very cool ... that must be Earth blue
#3066 Re: Unmanned probes » New Horizons - mission to Pluto and the Kupier belt » 2006-05-02 12:53:16
New update from Alan Stern (May 2006)
it's worth noting that we have just realized that New Horizons itself will be traversing through one of the Trojan regions of Neptune in 2014.
and
Our APL-based telecommunication team, led by Chris DeBoy, has worked out a way to use our redundant (opposite polarization) transmitters simultaneously to double our data rates.
#3067 Re: Human missions » Spacesuits - personal spaceship » 2006-05-02 09:10:16
Now back to or regularly schedueled space suits for the next big steps on a planet other than Earth.
Prototype Mars space suit to be tested in Badlands this weekend.
Dang no picture 
BTW Pablo de Leon, the project manager, gave an interview with the Space Show recently
#3068 Re: Human missions » NASA Exploration Roadmaps » 2006-05-02 06:20:41
Three BILLION for biology? Thats insane! NASA is a space agency, not a biology one. Let them petition the NSF for money like everybody else except where pertaining to humans in space or finding bacteria on Mars/Europa/etc. Cut the rest.
It's Human biology work, micro gravity adaptation etc etc. There's even more funding inside the R&A accounts of the science budget. This should be all about how to keep astronauts well in space, that six month plus trip to Mars and the return to Earth is a real problem. Right now astronauts wouldn't be able to do anything when they land on Mars except type on keyboards. Hey I'm fully trained, can I go please
#3069 Re: Human missions » Is the 'VSE' getting dimmer ? » 2006-05-01 10:37:26
Many have felt that the contractors for years and possibly decades have been bilking Nasa. Now Griffin seems to be saying it too, he has seen the light
It's good to hear Griffin remind his suppliers that he is the one spending over $100 billion with them and he wants value. Griffin surely saw the light a long time ago :>
#3070 Re: Human missions » NASA Exploration Roadmaps » 2006-05-01 10:30:26
The FY2006 budget request includes $753 million for continuing development of the CEV. As of 2005 the total development costs of the CEV are estimated at $ 15 billion
Is there a source for this estimate?
$15B seems rather high for just the CEV unless it's a projection over the lifespan of the vehicle. Adding across the Exploration row gives about $30B which includes the CLV and the LRO as well as initial work on the HLV/EDS/LSAM and almost $3B for human biology (adding the $881 million spent in FY2005), yes that's right $3 Billion for human biology .. it would have been double that if Griffin hadn't controlled the program.
#3071 Re: Human missions » NASA Exploration Roadmaps » 2006-05-01 04:41:06
The flyoff I think from the dates on the article searches seem to be around late 2004 to early 2005. Which means ya but only a single year but still makes it closer to 3. I see your point on the military process being of higher cost to Nasa initially but in the long run I thought that it would have cost less than the spiralling efforts....
And who ends up paying for the development of two prototype vehicles? Yes the customer of course. If there's plenty of money available this is a good competitive solution and may result in a better system. Pressure from the suppliers for the customer to pay for a prototype is also a factor, building real systems is good for everybody. It would be interesting to see a study done comparing fly offs with paper proposals.
Another factor is that military systems have production rates that exceed human spaceflight by orders of magnitude and the efficiency of manufacturing is important. This can be better evaluated when real hardware is produced.
The two CEV bidders, LM and Boeing/NG are in a competitive process right now. One will get the CEV and the other will probably get the Service module. This traditional way works, it's quicker and cheaper. Better always comes with a price tag.
#3073 Re: Human missions » Is the 'VSE' getting dimmer ? » 2006-04-30 05:44:49
As a critical component of any move to mars is a big ship (200m long) that is nuclear propulsion capable, unmanned because of its 10G capacity although it would have onboard manable habitat for technicians during repair and maintenance cycles, with a cargo capacity of 50,000 ton limit in a single standard module size.
The problem then becomes the ability to orbit a container of 50 metres length, 16 meter radius with an upper mass of 50,000 ton.
Unfortunately a vehicle with a two hundred year lifespan will carry that 1 million-billion dollar price tag.
Could you repost this in about 100 years please
#3074 Re: Human missions » NASA Exploration Roadmaps » 2006-04-29 14:35:35
As for the moon base, for three decades NASA has sent nothing to the moon, not even a robot probe.
Lunar prospector 1998
Clementine 1994
Amnesia indeed
#3075 Re: Interplanetary transportation » Ares V (CaLV) - status » 2006-04-29 06:49:19
I might drop the Ares Magnum name and call it Saturn VI to get more support.
Either name would be better than CaLV which is really confusing ... nah let's stick (haha) with HLV, that has a nice ring to it.