SpaceX rockets & launches

(Andrew D) #61

Yes. I had originally started writing a response describing the relationship of graphs of energy and power with respect to time, but it then inspired the speed-distance analogy.

(Daniel Sikar) #62

Ah, you are talking about a maximum value it both cases. Ok, I think I got
the comparison now, no time unit required.

(Barnaby Coote) #63

more like 1 joule is 1 watt applied for 1 second or a watt-second. Watts are not related to time

(Frank Scott) #64

Not really! Dermot had it right.

The SI system is built on the units of mass, length and time

So the unit of mass is the prototype Kilogram;
The unit of length the metre;
And the unit of time the second.

The units for force, energy, power and pressure/stress are derived from the base units.
From which the unit of force, the Newton which is the force required to give a mass of one kilogram an acceleration of one meter per second per second MLT^-2.
The unit of energy, the Joule which is the work done (ie energy) by a force of one Newton acting through a distance of one metre (ML^2T^-2).

So as Dermot said the the watt is derived from the unit of energy, the Joule.

And the Watt is a measure of energy usage per seccond (ML^2T^-3).

(Dermot Jones) #65

Just found some time to watch a bit of the presentation…“quite tectonic when it takes off” is an interesting line in reference to lift-off thrust of 13,000 tonnes!

(Dermot Jones) #66

A peer review of EM drive is published:

Real world (well space) teats in the next few months

(Dermot Jones) #67

There’s a launch on Sunday?

(Tom Newsom) #68


(Dermot Jones) #69

Hey! I think the members should have been consulted before you used our surplus to book this…unless the second ticket is for me…

(Rich Maynard) #70

Good news, the ticket is for you! Bad news, it’s only a single…

(Dermot Jones) #71

Not sure NASA a that impressed…

(Andrea Campanella) #72

I was bored , I put some space in the Makerspace…

(Toby Harris) #73

Cassini end of mission media went up yesterday. I’m going to be drinking on September 16th, and probably watching all the footage, ever.

(Andrea Campanella) #74

Losing Cassini will be like lose and old friend for me, I started to get in to rocket science and space when I saw the launch at the TV…

(Toby Harris) #75

…that’s why I’m drinking.

(Tom Newsom) #76

That’s a spectacular video :slight_smile:

It’s worth watching Wanderers by the same guy, which moves me to tears every time:

(fun fact: he also animated Crazy Frog)

(Toby Harris) #77

I’m telling you. Come that day, it’s me, some booze, and all that footage.

(Toby Harris) #78

This footage is amazing. They got the whole of the first stage in camera, at dawn, with little fluffy clouds; this is an edit but the whole thing is in the webcast.

(Tom Newsom) #79

Tonight’s launch is to the ISS, with the booster returning to Cape Canaveral for the landing. What makes this launch exciting for us here in the UK is that [URL=‘’]we should be able to actually see the spacecraft in the sky[/URL], before it’s even made its first orbit.

Launch is scheduled for 22:55 tonight, and it should fly above Southern England/Northern France 18 minutes later. Look West at around 23:13 (but I’d give yourself a few minutes beforehand - this isn’t an accurate prediction), just to the right of the setting moon. Dragon should arc across the Southern sky for about 2m30s before disappearing into the Earth’s shadow. The discarded 2nd stage should be flying more or less in formation, having only separated 5 minutes prior.

And then because it’s headed to the ISS’s orbit, it means that you’ll see the ISS follow the same trajectory a little later at 23:33.

If you head outside earlier in the evening, you’ll be able to see the ISS make a very close overhead pass at 09:57, from West to East almost directly overhead for about 5 minutes. This is about as good a view as you can get from here.

Now, sod off clouds.

(Dermot Jones) #80

Postponed due to lightning, trying again Saturday I believe. Will that launch be visible too? Or is that too much to ask?

It’s scheduled for 22:07 BST