A simple challenge for those who claim they like topics related to space exploration

[josephG]

@rodsky

you also did not mention the default location sa shuttle if its in the left or right side sa ISS...
where in imng diagram is opposite from your first illustration...

[rodsky]

Quote: Originally Posted by josephG @rodsky you also did not mention the default location sa shuttle if its in the left or right side sa ISS... where in imng diagram is opposite from your first illustration...

I don't understand what you mean. Klaro kaayo from the diagram that the shuttle is on the left side of the screen, and the ISS on the right side. Allow me to repost it:



Based from the F-16 diagrams, it's logical to infer that the shuttle and the ISS are moving "left to right" or in this case, orbiting the earth in a clockwise direction.

-RODION

[rodsky]

Ok, let's answer the question...how then, can Luke Skywalker reach the Death Star, or what is the shuttle supposed to do, to reach the ISS? Hopefully, the following diagrams will illustrate the solution:


Here, the shuttle and the ISS are on the same orbit (same altitude, thus same radius from the center of the earth). In this state, they will both revolve around the earth, and there will be NO CHANCE for the shuttle to reach the ISS if it doesn't do anything. So how can it reach the ISS?


First, the shuttle needs to turn around 180 degrees, pointing it's nose AWAY from the direction of travel, or away from the ISS. This is the counterintuitive part--to get to where you are going, you have to point towards the opposite direction!


Shuttle then fires its main engines, called the OMS engines, to change the shape of its orbit to an ellipse with a smaller radius than the ISS' orbit.


The shuttle is now coasting along its new, green orbit line...it's much faster than the ISS now, so it can overtake it soon.


Fast forward...Let's assume that both the ISS and the shuttle have orbited the earth about 30 times...because it takes a long time for the shuttle to catch up to the ISS...


Once the ISS nears...the shuttle has to turn around 180 degrees again, and POINT TO THE ISS...and then do another burn...this time it's the PROGRADE burn, so that its orbit ellipse will become bigger again...and thus slowing it down, allowing it to approach the ISS carefully.


It will then try to match orbits with the ISS, by continuously increasing apogee in little bits (via small prograde burns) until they're only a few hundred meters from each other, and by then, the shuttle can then slowly "drift" towards the shuttle using not its OMS engines, but the RCS thrusters.

And that, is how you get the shuttle to reach the ISS

-RODION

[bluedes]

here's more trivia for space shuttles and their operations.. in layman's terms..

How is the space shuttle configured and operated?
The space shuttle system consists of a main liquid fuel tank, two solid rocket boosters (SRBs), and the shuttle orbiter. When the shuttle is launched, the orbiter and SRBs are attached to the main fuel tank, and the tank fuels the orbiter’s three main engines. A few minutes after launch, the SRBs exhaust their fuel, detach from the main tank, and fall into the ocean; a parachute system slows their fall, and they are recovered for use in future launches. The main tank and orbiter stay together until low Earth orbit is achieved. When the main tank is empty, it is detached as well. It cannot be recovered and generally burns up in the atmosphere. The orbiter, with astronauts aboard, then goes on to complete the mission. This 184-foot (56-meter) long vessel contains engines, rocket boosters, living and work quarters for up to eight crew members, and a cargo bay large enough to hold a large school bus. It also has wings and is aerodynamically designed to be able to glide back to Earth from orbit, landing like an airplane on any runway long enough to accommodate a commercial jumbo jet.

Source: The Handy Astronomer Answer Book, by Charles Liu

[handsoff241]

Quote: Originally Posted by rodsky That's a very confusing statement. If the ISS is "not moving" with respect to the shuttle, then how can it "reach in time appropriate to his speed"? That's almost like saying "I will go to the store, but I will not move towards the store", diba? -RODION

You got me wrong.

The ISS is not moving with regards to the shuttle cause it only moves to keep a certain location with regards to the earth, therefore it moves very slow. The shuttle has a speed cause it is moving, and for the fact that you ask that if it needs to exert "more" thrust is a proof that it is moving.
So the shuttle can reach the ISS without adding additional trust.

Allow me to avoid the formulas'.

[josephG]

diagram A




diagram B


cgi ako klarohon from diagram A if luke increase speed yes mo shift cya to higher orbits which in return make lukes ship slower in respect to DS speed.

but for diagram B the shuttle approach ISS from left to right opposite sa earth rotation(counterclockwise) which again opposite sd sa diagram A. my question is mo shift to higher orbit ba ghapon ang shuttle if it increasis throttle?..

[rodsky]

Quote: Originally Posted by bluedes here's more trivia for space shuttles and their operations.. in layman's terms.. How is the space shuttle configured and operated? The space shuttle system consists of a main liquid fuel tank, two solid rocket boosters (SRBs), and the shuttle orbiter. When the shuttle is launched, the orbiter and SRBs are attached to the main fuel tank, and the tank fuels the orbiter’s three main engines. A few minutes after launch, the SRBs exhaust their fuel, detach from the main tank, and fall into the ocean; a parachute system slows their fall, and they are recovered for use in future launches. The main tank and orbiter stay together until low Earth orbit is achieved. When the main tank is empty, it is detached as well. It cannot be recovered and generally burns up in the atmosphere. The orbiter, with astronauts aboard, then goes on to complete the mission. This 184-foot (56-meter) long vessel contains engines, rocket boosters, living and work quarters for up to eight crew members, and a cargo bay large enough to hold a large school bus. It also has wings and is aerodynamically designed to be able to glide back to Earth from orbit, landing like an airplane on any runway long enough to accommodate a commercial jumbo jet. Source: The Handy Astronomer Answer Book, by Charles Liu

What you have posted has no bearing with (and thus cannot assist in solving) the problem I posed. If you're trying to provide information for those who lack information about the Space Shuttle, then thank you.

To those who want to see a retrograde burn in action, and how retrograde burns allow the shuttle to raise/lower its orbit, or allow it to return to earth, using a high fidelity space shuttle simulator (Orbiter), allow me to demonstrate it myself:

YouTube - Simulated Shuttle Deorbit-to-Landing - 1 of 3

YouTube - Simulated Shuttle Deorbit-to-Landing - 2 of 3

YouTube - Simulated Shuttle Deorbit-to-Landing - 3 of 3

-RODION

[rodsky]

Quote: Originally Posted by josephG diagram A diagram B cgi ako klarohon from diagram A if luke increase speed yes mo shift cya to higher orbits which in return make lukes ship slower in respect to DS speed. but for diagram B the shuttle approach ISS from left to right opposite sa earth rotation(counterclockwise) which again opposite sd sa diagram A. my question is mo shift to higher orbit ba ghapon ang shuttle if it increasis throttle?..

The direction (clockwise or counterclockwise) does not matter if BOTH Shuttle and ISS are headed in the SAME direction, as can be logically inferred to in the diagram.

Yes, the shuttle's orbit will "inflate" into an ellipse larger than the ISS' orbit, mao nga it will slow down, and thus it will DRIFT AWAY from the ISS, instead of getting closer to it.

-RODION

[rodsky]

Quote: Originally Posted by handsoff241 You got me wrong. So the shuttle can reach the ISS without adding additional trust.

Totally incorrect statement. Refer to the first image in my solution above...


As you can see from this diagram, two bodies (in this case, the ISS and the shuttle) sharing the same orbital altitude HAVE NO MEANS to reach each other unless one of them changes orbital radius, and this can only be achieved if you either do a retrograde or prograde burn.

-RODION

[ethzneuron]

and i quote:

Quote: Originally Posted by ethzneuron mo-catch up ang shuttle towards IIS using reverse thrust meaning iyang thrusters kay pointing towards IIS. then after the burn kay "the spacecraft is actually moving faster!". so, mapaduol nani siya sa IIS.

what's the name of that big thruster sa likod sa shuttle? mao ning OMS...??

nice... next topic sir rods. lain na sad na thread. ^__^

[rodsky]

Quote: Originally Posted by ethzneuron and i quote: what's the name of that big thruster sa likod sa shuttle? mao ning OMS...??

-RODION

[ethzneuron]

Quote: Originally Posted by rodsky Shuttle then fires its main engines, called the OMS engines, to change the shape of its orbit to an ellipse with a smaller radius than the ISS' orbit. -RODION

abi nako mao nani gud.. thanx sir rods. at LEO kaning OMS mao naman sad mahimong main engine kay hurot naman pod ang big 3 thrusters.

[Lovely Charm]

hav u guys flown a space shuttle na?

[rodsky]

Quote: Originally Posted by ethzneuron abi nako mao nani gud.. thanx sir rods. at LEO kaning OMS mao naman sad mahimong main engine kay hurot naman pod ang big 3 thrusters.

Yes, in a simulation I would consider them my "main engines" (as opposed to RCS thrusters), but I don't know what real astronauts call them once in LEO

-RODION

[rodsky]

Quote: Originally Posted by Lovely Charm hav u guys flown a space shuttle na?

Only NASA astronauts have the opportunity to "fly" (I use quotes because most of the time, you basically just "guide" the shuttle...the flying part only occurs the last few minutes before landing it at the cape or at Edwards) the space shuttle. Not even qualified ESA or RSA pilot/astronauts (who regularly ride the shuttle to the ISS) are allowed to act as commander/pilot on the shuttle.

However, those who have access to Orbiter, can experience flying the shuttle and doing operations in LEO, all within the confines of a simulated environment nga very strict when it comes to Newtonian/Galilean physics and Kepler's laws.

Orbiter (simulator) - Wikipedia, the free encyclopedia

Orbiter - A free space flight simulator

I've been an addon developer for Orbiter for over 7 years now, and yes, I've flown various types of addons meant to simulate complete STS operations.

-RODION