Flying Inverted At Escape Velocity To Change Course and other Questions - Deep Space Questions 19

regarding the JWST thrusters: JWST has 2 sets of "big thrusters" (called SCAT), one for the mid-course correction burns with a thrust vector through the stowed center of mass, and one set for the final insertion and station keeping burns with a thrust vector through the deployed COM. the SCATs are bi-propellant and the "small thrusters" (called MRE) are mono-prop. the MREs are used for attitude control during SK burns and for momentum unloads. the specific impulses for these are what you'd expect for these types of engines and the propellant lifespan that NASA is giving is highly reliable and on the conservative side, assuming everything goes to plan. source: I worked on JWST

Scott Manley always help me learn. Tomorrow I will fly to Laythe in a safe.

13:04 Thanks for talking about skyhooks! Much more practical than space elevators

My personal preference for orbital access is the orbital ring, where you have a ring in LEO with elevators going up to it from multiple points on the equator. It's held up with mass travelling around it faster than LEO orbital speed. Make that fast mass be an inner section, and it can even be lower than any stable orbit, as the outside skin would be stationary. The fast mass could also be used as a catapult to send ships/cargo into higher orbits.

The "momentum exchange tether" described @13:03 is in the novel Seveneves by Neal Stephenson

for more detailed looks into space elevators and sky hooks i highly recommend Isaac Arthur's "Upward Bound" series

Probably worth noting that reaction wheels basically work by storing angular momentum, and eventually they get saturated; at this point a conventional thruster is used to cancel this stored angular momentum and return the reaction wheel to normal operation. There's an article on wikipedia about it.

8:40 First "realistic" attempt at space war I read was in Harry Harrison's To The Stars Trilogy (1981). The story as I recall it: Nobody had ever fought an actual battle in space, but the Earth government had ships carrying nuclear missiles. Beam weapons existed, but beam divergence meant they were useless at the engagement distances in space. The rebels came in with a bunch of kinetic-kill weaponry (rapid fire cannonballs and clouds of flechette) and overwhelmed them. I also remember the Traveller roleplaying game (late 1970s) introduced "sand casters" which interfere with other types of weapons (ablative to beams and damaging to missiles), similar to real world "shotgun" anti-satellite weaponry.

When I see those pictures of James Webb's sunshield unfolding, I'm always reminded of some 19th century sailing ship. And when you come down to it, the JWST is a tall ship, with stars to steer it.

17:20 - Blaise cary's Q1: Some historical examples of rocket stages with tanks side by side are first stages of the Proton, Saturn 1, and Saturn 1B all were designed with a central propellant tank and six (Proton) or eight (Saturn) smaller tanks equally spaced around that central tank.

The spiraling elevator reminds me of the Bolo’s from the book seveneves

Spitting these out. Man I love it

Hello Scott, I really enjoy your content on this channel. My son steered me to this. I have learned so many interesting things, example: why a person cannot throw a baseball to land on earth from orbit. Hope you continue this for a very long time.

7:31 I like how your hand movement synced with the screensaver!

I really like the idea of the skyhook too

Ah, you mentioned the space yeeter, my favorite space elevator alternative. Work even better with the Loftstrom loop!

Scot, thanks again for the public update to questions.

13:42 I really like your pinwheel idea

Flying Inverted At Escape Velocity pretty much sums up my cats day. Her relentless efforts to gnaw of my computer cable finally payed off this afternoon. Let me tell u, there are a surprising amount of Delta V in an electrocuted cat.

That was an interesting twenty minutes. Thanks!