A quick overview of what’s due to go up/come down in January and February:
Dragon on Falcon 9 (SpaceX): Dragon, made and launched by the private company SpaceX, will demonstrate approach to and docking with the International Space Station per their COTS contract. Currently the target launch date is 7 February, but this may be pushed back by a few days (the launch window each day is pretty small). Upon launch, the unmanned capsule will synchronize orbit with Station, practice maneuvers at a safe distance, and finally approach for docking. Astronauts aboard the station will grab Dragon with the Canadarm2 (eh!), and guide it to the PMA-2 dock on Node 2, between the European and Japanese lab modules (at least, that’s what the SpaceX pictures show). This will be the first time a privately-owned spacecraft has docked with Station.
The Falcon 9 rocket is also made by SpaceX; it is a two-stage rocket with nine LOX/kerosene engines in the first stage, and one LOX/kerosene engine in the second. Both Dragon and Falcon 9 are currently at Cape Canaveral in preparation for the launch. Continue reading
Monomethyl hydrazine is based on hydrazine, which has the chemical formula N2H4. Hydrazine is also used as a propellant and is both unstable and toxic. It may be used as monopropellant (usually after being run through an appropriate catalyst bed), or more commonly as a bipropellant, being hypergolic with nitrogen tetroxide (NTO). Applications of hydrazine have included propelling the Me163B (the first rocket-powered fighter, WWII), on the Viking and Phoenix lander descent engines, and powering F-16 emergency power units. Notably, the thrusters on the spy satellite USA 193 were fueled with hydrazine; an interesting article on the role of hydrazine in the satellite shootdown is here: http://spectrum.ieee.org/aerospace/satellites/us-satellite-shootdown-the-inside-story
Monomethyl hydrazine (MMH) is the result of replacing one of the hydrogens in hydrazine with a methyl group, CH3. It is more stable than hydrazine (can be used in regeneratively cooled engines), and is thus favored as a storable propellant. Because it is still toxic, as well as a suspected carcinogen, great care is taken in handling it. It is most commonly used in hypergolic combination with NTO, such as in the Space Shuttle’s Reaction Control System (thrusters). MMH decomposes into mainly H2, with some CH4, N2, and trace amounts of NH3 and C (soot).
“First of all,” my sister writes, “you should post on what your project is/is trying to accomplish.” … All right, my objective: Characterize the behavior of dual flame fronts in gelled MMH/gaseous NTO as NTO diluent partial pressure and type vary.
This is the simplest way to summarize my project while still preserving the technical aspect. It does, however, lead to a slew of questions: What is involved in “characterizing”? What is a dual flame front? What do MMH and NTO stand for and what are they? Why would you gel them? Why is diluent involved and what am I using? And how does this help babies in Africa?
Below are some photos from a typical testing day. This is mainly for my family or other people who wonder what I’m doing when I say, “I have to go to work”, or, “I got to make fire yesterday.”
The dry box: actually stocks invented for chemists. It allows us to maintain a nitrogen environment for things that don't like oxygen.
the fifth of November … Odd how an extremist reviled for treason has morphed into something of a popular hero. Thanks, V for Vendetta. Not that it isn’t an interesting movie, but it does highlight some of the reversals in Western values over the past five hundred years or so.
I’m killing time until my currently unpopular office hours are over, since I’m extremely unmotivated to study for my STAT exam or work on my MECH problem set.
I’ve realized, over the past month or so, how often I and other people say “I feel that…” when we actually mean “I think that …” Feeling is not the same as thinking, and I think that when we don’t make a distinction between the phrases, we contribute to blurring the lines between the two. “I feel that…” might be deemed a less assertive or offensive phrase, but I think that sacrificing passivity in favor of clarity is not a bad thing. Consequently, I’ve been using the word “think” a lot more in the past few weeks. Words and word choice are important.
Two minutes, so some notes in random order:
- There is a Pandora gadget!
- I’m getting more motion in my right knee after ACL surgery. Thank you so much for all y’all’s prayers and notes/cards/messages! I will reply individually, but I can’t promise a timeframe yet. Eyyy grad school.
- I have a roommate for next semester! The way in which it all happened was definitely Providential and I shall detail this at some point.
- Model rocket launch for a class I’m TAing. I put some pictures on Flickr.
Alright, now I have to go be productive.
or, What I’m Doing for Summer Vacation. Contrary to popular opinion, my summer employment is not Classified, Top Secret, Need to Know (right now, I have mental pictures of these words stamped in red ink) or anything else that prohibitive and therefore enthralling. There are parts that involve export-restricted and proprietary stuff, though, so for those I’m not going to write anything that isn’t published or publicly available.
Here’s the scoop. There are several companies that are taking on the challenge of commercial spaceflight; among them are Virgin Galactic/Scaled Composites of Ansari X-Prize fame, SpaceX, and Armadillo Aerospace. Also included is Blue Origin, owned and funded by the founder of Amazon.com. In addition to having headquarters near Seattle and a launch site in West Texas, I’ve heard that they also have in their lobby a model of Jules Verne’s projectile-vehicle from his novel From the Earth to the Moon, as well as a door from the set of Battlestar Galactica. Cool. Continue reading