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First time to the Grey planet. Someone can help me?


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Hello KSP users. Alien21 Space Agency has evaluated to plan a mission to the most strange planet. Maybe isn't correct call it a planet, but Dres seems in a great position for a launch and we're evaluating to do a direct mission to that undiscovered planet after our first fly by to Eve.

Our MCC (maybe it could be better call it https://alexmoon.github.io/ksp/ ), has calculated for us these data which seems helpful for reach the target, but someone can explain us how to use it?

If our intial orbit around Kerbin will be at 100 KM with a Balistic profile:

Departure
Year 3, day 117 at 2:38:24
Arrival
Year 4, day 284 at 5:20:24
Time of flight
1 years 167 days 2:42:00
Phase angle
61.20°
Ejection angle
120° to prograde
Ejection inclination
1.01°
Ejection Δv
1,530 m/s
Transfer periapsis
13,337 Mm
Transfer apoapsis
39,726 Mm
Transfer inclination
0.15°
Transfer angle
182°
Insertion inclination
14.90°
Insertion Δv
1,544 m/s
Total Δv
3,074 m/s
 
So phase angle is basically the angle where the target will be located in front or behind our departure planet (in this case it will be in front of us)
Ejection angle will be basically the angle where we will start our transfer maneuver, and this exact angle will allow us to leave Kerbin SOI and leave the planet to its own orbital prograde or retrograde heading.
Ejection inclination: what is? is the angle which must be added from our planned transfer maneuver if we would leave the equatorial orbit and start the interplanetary flight?
Ejection Delta V: simple, the speed required for this maneuver.
Transfer Periapsis and Transfer Apoapsis: Are maybe the data about the Kerbol Orbit when we will fly around the sun?
Transfer inclination: will be the inclination in comparison to Kerbol Star during the flight?
Tranfer angle: will be the total angle from our departure position to our destination position looked from Kerbol?
Insertion Inclination: I think that will be the angle of difference with the equatorial line of our destination.
Insertion Delta V: another speed which must be planned if I would get an orbit (possible something which could be great, but not sure if required for achive this mission, also a fly by will be appreciate)
Total Delta V: the speed required for the travel, really, I don't think that someone could have question about this :):):)
 
If someone will be able to explain me this, will be appreciate his-her help. In addition, if you would share with me your agency flag if you would see also your flag on my space probe, will be a pleasure do it.
 
Of course, if someone will be able also to tell me how to calculate manually any interplanetary travel, will be a pleasure learn and try personally your precious sources. This game is really amazing if you would learn phisics.
 
 
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Guest The Doodling Astronaut

Looks nice. The delta v amounts I use on a Dres mission usually is sorted into this amount:

-3400 for Kerbin orbit

-2500 for Dres insertion and Kerbin escape

-500 for adjustments

Depending on how good you are at insertion, capture will be around 1500 to 4500 m/s.  Then a similar style to how you would land on Mun (so pack 1400 for landing and circulization)

I added some fuel to each number so that you can  have some area to spare. I'm assuming since this is your first time that you would want these numbers.

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Alien21 Space Agency here. Mission "Grey World" was launched with success with a balistic orbit with an Atlas V 551 stock replica. It was required however a second maneuver for adjust the balistic trajectory in order to allow our probe to join the Dres SOI.

In case at this point, someone will still continue to have question like I had previously, I will explain all details.

My question was:

Ejection inclination: what is? is the angle which must be added from our planned transfer maneuver if we would leave the equatorial orbit and start the interplanetary flight?

Answer: Yes, this could be positive or negative. In case the value is positive, this mean that you must deviate to the north pole of Kerbin while you will do the transfer maneuver. If it's negative, your direction must going to the south pole.

Transfer Periapsis and Transfer Apoapsis: Are maybe the data about the Kerbol Orbit when we will fly around the sun?

Answer: after the balistic maneuver, will be exactly that data if the transfer maneuver will be done exactly (this it could be harder, but not impossible)

Transfer inclination: will be the inclination in comparison to Kerbol Star during the flight?

Answer: yes, like the previous question

Insertion Inclination: I think that will be the angle of difference with the equatorial line of our destination.

Answer: yes, but to be honest, don't take this value so much as relevant. With the planets with a significant inclination around Kerbol star, is really harder get all these data exactly.

I will show you at this point the photo of the probe when I will reach Dres! Luckly it could be possible also download from gitlab the Launch Transfer Window of alexmoon!

 

 

 

 

 

Edited by Alien21
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On 10/13/2021 at 11:18 PM, Alien21 said:

Of course, if someone will be able also to tell me how to calculate manually any interplanetary travel, will be a pleasure learn and try personally your precious sources. This game is really amazing if you would learn phisics.

Calculate? No. Eyeball? yes.

 

for start, you go from Kerbin to Dres, Dres moves slower because it is farther from the sun, so you need Dres in front of Kerbin. By how much exactly? No idea, but I eyeball them by trying, from Kerbin, a prograde burn until I hit Dres orbit. For efficiency, make sure to start in the right place; move the manuever node slowly, you'll see that the apoapsis will change. Find the position where you get the highest apoapsis. Be aware that it will change if you change the deltaV, so keep adjusting. eventually you will find the cheapest prograde burn to intercept dres orbit. You also need to set up a plane change, though it's generally not the best way to reach dres. When you match planes, you will see a close approach marker. If you're passing in front of your target, you have to wait. if you'll pass behind, the transfer window has passed. this way you eyeball a transfer window

2bo5WKd.png

this method applied to a sarnus-jool transfer. my spaceship would reach jool's orbit before the passage of jool. By roughly eyeballing the angle and jool's orbital speed, i estimated waiting one to two years.

 

this is also a good way to reach your target with an efficient burn; when you do it at the right time, you'll get an intercept, or at least a close approach that's close enough that you can get there with some small corrections.

cbHMQeK.png

indeed, two years later i easily got an approach.

close approach was very close, at this point it's just a matter of fiddling with all the directions and seeing what will cause you to pass closer to the planet.

 

 

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