I'm not sure if my understanding is correct, but these thruster pods are used to de-orbit the spacecraft too, right? I wonder if only one module has enough juice to de-orbit the spacecraft and retrieve it intact, if they end up needing to do that.
Yes. He said they would stay up there at least a month trying to get it to work. If they return to earth they lose one of the cargo trunks that is designed to burn up in re-entry.
They do need to wait for the Dragon (and ISS) to travel a bit in their respective orbit until another opportunity comes up for rendevouz. Theres some concern that the Dragon might get too low and reenter, so they will probably have to expend fuel to stop that from happening.
My understanding is that NASA gets final say, and that needs to happen about 24 hours ahead of time. I believe tomorrow afternoon NASA will make that decision, and then Dragon will go into an orbit that will intersect with ISS's.
I'm very happy. Not as happy as if there were no hiccough (SpaceX has some big enemies and they will be harping on this with the FUD), but things are playing out nicely.
Yeah, I thought the Dragon looked a bit driftier than usual, after separation. Glad to know it's alive and talking, if not necessarily in good health. Let's hope they can nurse it back.
It sounds like they're going to have to manually put it in orbit. Probably something happened to the software that auto initiates the thrusters to put it in the right trajectory. I'm just guessing as I'm no Rocket Scientist.
It's in orbit already. The question is whether they'll be able to get Dragon to the station. Most likely it's either a software bug or a faulty sensor -- the vast majority of aerospace problems are generally attributable to one or the other.
Eighteen Draco thrusters are used on the Dragon spacecraft for attitude control and maneuvering. Dual-redundant in all axes: any two can fail and still have complete vehicle control in pitch, yaw, roll and translation.
Four Draco thrusters are used on the Falcon 9 second-stage as a reaction control system.
I've looked at some pictures, and I think a thruster "pod" is a collection of 4 thrusters, all pointing in different directions. It looks like there are 4 such pods arranged around the edge of the Dragon capsule. That would account for 16 or the 18 thrusters.
Two of the pods have 5 thrusters. Those pods have two thrusters point "up". That give a total of six pointing "up". These are the thrusters used for the deorbit burn and having two extra is for redundancy
FRIDAY, MARCH 1, 2013
1527 GMT (10:27 a.m. EST)
"It appears that although it achieved Earth orbit, Dragon is experiencing some kind problem right now," said John Insprucker, SpaceX's Falcon 9 product manager. We'lll have to learn about the nature of what happened. According to procedure, we expect a press conference to be held a few hours from now. At that time, further info may be available."
FRIDAY, MARCH 1, 2013
1524 GMT (10:24 a.m. EST)
ANOMALY. SpaceX is reporting some type of anomaly on the Dragon spacecraft. Deployment of the solar arrays was supposed to occur at T+plus 11 minutes, 45 seconds, but on-board cameras did not show the panels unfurl as planned.
SpaceX's webcast cut away from the solar array view and went to a slate.
It's normal for any NASA mission. Your average comsat launch isn't going to get any press coverage, and the military sure isn't holding press conferences after their classified missions. But pretty much every NASA science and space station mission is going to get a lot of interest.
FRIDAY, MARCH 1, 2013
1736 GMT (12:36 p.m. EST)
"A NASA official says three Dragon thruster pods are required to approach the International Space Station."
Is there any chance of them getting all three thruster pods active? If not, will they have to abort the mission?
There are four pods. One is working already, so they need to reactivate two of the three that are squelched. They have telemetry, and solar power, so that gives them time to work on the problem; battery lifetime is not a constraint.
But if they can't get this solved, the delivery can't happen, and the cargo is likely lost. They could try to recover some of it by bringing the Dragon down, and hoping the chutes work --- if they've got enough fuel and control to do that in a controlled way. But that would still result in the loss of the unpressurized cargo in the "trunk", which is separated and burns up on reentry, and also probably some time-sensitive experimental material inside the Dragon itself.
Is there any chance NASA will let them go ahead with two pods? I see that only two are required for full control of the craft, but I assume NASA wants three for redundancy in case of a failure.
The latest is that Saturday's docking has been scratched. It takes about a day to get into position.
Dragon is still up there and orbiting and will probably continue to do so for several days without effort, so SpaceX still has an opportunity to fix what's wrong.
I'm really, really interested in space and astrophysics, but I'm working full-time.
(studied a bachelor in IT, with minimal maths and physics)
A degree in astrophysics is at least 5 years, which is impossible for me.
What books / material can I study on my own to perhaps try the degree in 2 or 3 years full-time?
You don't mention if your interest is about working in the aerospace industry which would imply getting a degree in mechanical, electrical or aerospace engineering or if you would like to work in some other areas such as research in astrophysics. I'm going to assume the former since that is where I can give you some hints ;-)
You can pretty much work through the first two years of any technical degree by yourself by using online learning materials. Math is essential, so calculus, differential equations and linear algebra need to become something natural for you. You don't need to get fancy, standard undergraduate materials will get you through your bachelors, but if you are good at it keep on trying new things and learning as much math as you can, you won't regret it.
Physics is essential, and it can be harder to grok than math sometimes. You need to understand what the concepts and ideas mean, and be able to manipulate them with ease. Classical mechanics, besides being one of the most beautiful subjects in physics, is probably the most important one you will ever learn for your undergraduate degree. Also, physics requires math, lots of it, applied in creative ways. I learnt more math in a mechanics 1 class than in any other course I had ever taken. I recommend getting some minor or even better a dual degree in physics, but I realize this might be too much for some people.
You also need to know how to program, Matlab, LabVIEW and also C, C++ or Python are really popular, depending who you ask. knowing many languages well will put you a notch or two above everyone else when it comes to employment.
Finally, I would like to say that the space field is very very broad and there are multiple ways to make a career in it. Try to leverage your experience with computers, try moving towards the hardware side, learn about Arduino and embedded programming, complete a couple of fun projects and see if you like it. Maybe you will be better served by getting a degree in electrical than in mechanical engineering, there is no right answer. Try your best and if you decide to go through keep going at it no matter what, the payoff is definitely worth it. Good luck!
First off the job market in astrophysics is tight.
If you are close to an undergrad get that first, and then go for a masters as a masters only takes 2 years and it's much harder to get into astrophysics with an undergrad degree. Look into what courses they require for a masters in a school you want to go to and then study what you need to be to get ready for that. You can generally pick up the required books with little effort. If you don't understand them then that's what you study.
Depends on what you want to learn about, a degree in astrophysics or aeronautial engineering prepares you for many different possible jobs. I'm in a somewhat similar situation, maybe this will help:
(DISCLAIMER: I am not an aerospace engineer by training)
Calculus:
You'll definitely need to be very comfortable with single variable calculus and vector calculus up to partial derivatives, vector calculus integrals (Green, Stokes, Gauss) will definitely help. I wouldn't learn that from a book, try MIT's OCW, there is a calculus course covering all that. Learn the basic about ODEs, and be comfortable around PDE notation.
Linear Algebra:
In some sub-disciplines such as control and signal processing you'll also need to be very comfortable with linear algebra, so that all those matrices and stuff don't get in the way when learning modern control/DSP. I definitely recommend Prof. Strang's course in OCW for this. Try to at least be comfortable with simple ODEs before starting it. Linear algebra also helps a lot with Physics.
To get more into lineal algebra maybe you can read Linear Algebra Done Right if you want to learn more about Hilbert Spaces, and then maybe Shilov for tensors... those two books should be optional...
Software:
You don't need to be fast or maybe even know how to solve complex integrals in pen and paper. Try to complement learning calculus, differential equations and linear algebra with learning Matlab/Simulink and Mathematica. I can't even find a word to emphasize how much Matlab/Simulink is used in aerospace engineering...
Dynamics:
Learn classical mechanics, lots of it. Be confortable with rigid body dynamics in 3D. This is the best reading guide I know about, oriented to game development, but also useful for simulation and control: http://chrishecker.com/Physics_references Code simulators, visualizations, etc... Know what rotation, nutation and precession are, when and how they happen, etc...
From that list I have read a little of Goldstein and some Symon. If you find this books too hard, don't follow the guide but instead jump directly to the Feynman lectures (if you want to read) or Physics I from OCW (Prof. Lewin course, really really good).
Physics II from OCW can also help, maybe.
Space:
Once you are not scared with simple problems from all the previous subjects and can solve them, and can understand complex ones you should have no trouble following the first chapters (about dynamics, orbital and attitude maneuvering, etc) of some classical but real space books, for example:
You can also browse here: http://astrobooks.com/ and see if you find something particularly interesting. I really would like to recommend a more engaging approach and less boring books, but this is the best that I can come up with now.
After you can comfortably read the first chapters of those space books you should really choose what to focus into. Dynamics, Simulation, Finite Element Analysis, Mechanics/Thermal engineering, Signal Processing, Control... then learn the basics of that discipline and then try to apply it to space exploration or spacecraft design. Each of this disciplines would need their own reply and reading list I guess... some require more physics than rigid body dynamics, like fluid dynamics or thermodynamics, electromagnetism, etc...
Also, as usual, try to have fun but still be disciplined about reading/learning.
If you just want to extend your pop science knowledge, going for a degree and even most OCW courses would be overkill. I went through a bachelor's and master's in aerospace engineering, and they are not to be taken lightly; 24% of engineering students dropped out after freshman year at my university. The only book I recommend for you is Fundamentals of Astrodynamics (BMW); it's an approachable introduction orbit design/analysis that you should be able to take on knowing calculus through differential equations.
As noted elsewhere the issue is with the software inhibiting the activation of the thrusters. They delayed solar panel deployment because the capsule doesn't have attitude control yet.
SpaceX says one thruster pod is working, and two are "preferred" to deploy solar arrays. Four thruster pods are on the Dragon spacecraft.
"We are working to bring up the other two in order to plan the next series of burns to get to station," a SpaceX spokesperson says.
And at 11:40 EST:
"Thruster pod 3 tank pressure trending positive. Preparing to deploy solar arrays," Musk just tweeted.
At least two thruster pods are needed to deploy the power-generating solar arrays, which stretch 54 feet tip-to-tip.
So it's looking positive that they'll recover from this.
The date today is 1 Mars, 2013 (in Quebec, anyway). I tweeted this to Elon, but I guess he's pretty busy launching spacecraft. I'm so excited for this launch! The more routine these get, the better.
Edit: https://twitter.com/elonmusk/status/307515784610058241
Edit 2: Follow-up tweet from him: "Holding on solar array deployment until at least two thruster pods are active"
Edit 3: Looking better! Latest tweet: "Thruster pod 3 tank pressure trending positive. Preparing to deploy solar arrays."
Edit 4: YES! "Solar array deployment successful"