Matching longitude of ascending node for satellite contract

[Turbo Dad]

I have a contract to position a satellite into a synchronous network around Minimus. The inclination is 180 deg and height of 350km which I have matched, but I can't figure out how to match the longitude of ascending node of 279.1 degrees. Any hints chaps? Stock or mechjeb 

[bewing]

In map mode, do you see the orbit displayed that you are supposed to match?

At one of the points where your orbit crosses the target orbit, you will need to do some combination of Radial in, Radial Out, and maybe some Prograde and Retrograde burns.

Other than that, a 180 degree retrograde orbit does not technically have a LAN, because the orbit is exactly over the equator, so there is no ascending node.

Edited June 27, 2018 by bewing

[Reactordrone]

7 hours ago, Turbo Dad said:

I have a contract to position a satellite into a synchronous network around Minimus. The inclination is 180 deg and height of 350km which I have matched, but I can't figure out how to match the longitude of ascending node of 279.1 degrees. Any hints chaps? Stock or mechjeb 

A 180 deg inclination means it's a retrograde orbit. When you mouse over the AN or DN do they read 0° or 180° ? They should read 0° since they're relative to the target orbit.

[Turbo Dad]

Morning, yeah the an/dn read 0.

Have tried burning in every direction in various parts of my orbit to no avail. Also tried changing to an polar orbit then burning at the poles to change LAN to correct figure but when I drop my inclination back to 180 the LAN changes dramatically 

LAN readout on mechjeb 

[bewing]

On 6/27/2018 at 2:45 AM, Turbo Dad said:

Have tried burning in every direction in various parts of my orbit to no avail.

We need you to post a picture in map mode. To post a pic, you need to use an image server such as imgur.

 

 

[Kryxal]

The "match this orbit" type of contract tends to be easier to do by looking at the map instead of going by the numbers given.  Still, seeing the map view (with focus on Minmus) should help.

[Turbo Dad]

forum doesnt like my google link for inserting pics

[mystifeid]

Shouldn't the first part of the contract - "Build a new probe that has an antenna and can generate power" - have a green tick beside it?

[bewing]

Yeah, it's a little confusing since minmus has the focus -- but I think mystifeid is right. The ship with the blue orbit is the active vessel, so the first subclause of the contract is toast.

 

Edited June 27, 2018 by bewing

[Turbo Dad]

Ran out of fuel trying to match LAN so loaded previous save to try again. . The ship matched contract clauses. Screen shot was after reload ,not had chance to launch again. 

[mystifeid]

I've never had to worry about the longitude of the ascending node in an equatorial orbit. I do worry about overlaying the Pe and Ap markers more or less perfectly (yours are a little out of position) over the required ones at the right altitudes and also that my orbit is pretty much perfectly inclined. (Your screenshot is fairly low-res and I can't read the numbers). Around Minmus it might help to limit thrust/throttle to achieve these things.

But without a green tick next to that first requirement you are wasting your time. Make sure that:

- the ship was built after the contract was accepted.

- it is unmanned.

- it has an antenna.

- it can generate power (eg solar panels)

Edited June 28, 2018 by mystifeid

[Superfluous J]

1 hour ago, mystifeid said:

Make sure that:

- the ship was built after the contract was accepted.

- it is unmanned.

- it has an antenna.

- it can generate power (eg solar panels)

- it never docked to a ship already in space. IMO it shouldn't matter, but frequently (if not always) the time stamp of the older craft leaks through onto the newer one after you've docked them. And once you're at that point, the ship is considered too old to complete the contract.

EDIT:

This is why I wish instead of:

• Build a new, unmanned probe that has an antenna and can generate power.
• Have a Mystery Goo
• Reach The Correct Orbit

It said:

The probe must:

• Be built after the contract was accepted
• Be unmanned
• Have a transmitting antenna
• Be able to generate power
• Have a Mystery Goo
• Reach the correct orbit.

That way you can see instantly what (the game thinks) you're missing out on.

Edited June 28, 2018 by 5thHorseman

[Turbo Dad]

 

Relaunched ship , all boxes ticked apart from stable orbit .

hopefully better screenshot for you guys

 

https://imgur.com/sDjw1aR

 

 

Edited June 28, 2018 by Turbo Dad
problems inserting image

[bewing]

Well, whichever mod it is that created that contract has a bug then.

[Turbo Dad]

no contract changing mods, only mechjeb , chatterer, for science, docking port alignment .

[bewing]

Unless the wording's been changed on one of the stock contracts, that's not a stock contract. Therefore, it came from somewhere.

Additionally, you have two sentinel contracts listed, and those are supposed to be limited to one at a time -- so something is off about your contract system.

Edited June 28, 2018 by bewing

[Turbo Dad]

Sorry dude , but definitely stock, first time playing new dlc. Never even looked/downloaded at any other mods that change contracts. Only using the mods listed above.

mods list screenshot

any help if i post logs or something?

 

Edited June 28, 2018 by Turbo Dad

[The Flying Kerbal]

Actually Turbo Dad you have my full sympathy with this one because I too have had trouble getting contracts to complete even though all the conditions were met.  And while you do have a few mods, although they shouldn't be having any affect on this contract, my KSP 1.4 was totally stock, not KER, Chatterer or anything, but I never did get one to complete.

At least I didn't fly all the way to Minmus to have this problem, it was a simple engine test in flight over Kerbin; I tried it on numerous occasions, everything was green ticked, but that contract just wouldn't complete.

Finally I just got totally frustrated, deleted the saved career and went back to KSP 1.2.

Not a pile of help this answer I know, but at least it might help stop you from thinking this problem is definitely your fault.

Oh forgot, just a quick point, I tend not to get too excited about the An and Dn, as long as the Ap and Pe are right, I find the satellite contracts always seems to complete - at least in KSP 1.2.

Edited June 28, 2018 by The Flying Kerbal

[Turbo Dad]

First off all I fulfilled a contract to place a relay in minimus orbit at 172deg inclination,  after completion, I circularised and moved the orbit to 180 Inc.( as 172 looked messy,  I'm a bit ocd! ).

Then subsequent contracts were offered to utilise the existing satellites to form a network at this new  circular 180 inclination.

I think moving the first satellite to 180 circular caused a problem with the new contracts showing a Longitude of ascending node on a equatorial orbit. 

[Turbo Dad]

1 hour ago, bewing said:

Unless the wording's been changed on one of the stock contracts, that's not a stock contract. Therefore, it came from somewhere.

Additionally, you have two sentinel contracts listed, and those are supposed to be limited to one at a time -- so something is off about your contract system.

Unless someone has broken into home and installed hidden mods or hacked my pc, there is not, and never have been any mods that change contracts!!!

Can you check to see if wording has been changed?

 

Can't remember if I accepted the first sentinel contract for Kerbin, then launched, then accepted Duna Sentinel,  or accepted both at same time

[bewing]

4 hours ago, Turbo Dad said:

Can you check to see if wording has been changed?

OK, I'm wrong. That contract type is indeed a newish stock one that I haven't seen before.

So yeah, did you accept this contract before you upgraded KSP versions?

Can you post a copy of your savegame before you launch the sat toward minmus?

 

[Turbo Dad]

Brand new game started after I installed new version and dlc.

Game save

[OHara]

On 6/26/2018 at 4:20 PM, Turbo Dad said:

but I can't figure out how to match the longitude of ascending node of 279.1 degrees

The ascending node is where the orbit crosses the celestial equator (which happens to be the galaxy line in the KSP sky map) measured in degrees from the direction straight outward from galaxy center.  I had no idea what the reference direction was, but there happened to be a recent thread where someone knew.

Usually, as everyone said already, you can ignore the numerical celestial longitudes of orbits, because you can see the orientation of the target orbit in map-view.  But with a 180° orbit you can't tell where the game thinks the orbit crosses the equator, because the orbit stays on the equator; the LAN is undefined, but the game seems to require you to get it correct anyway.  This seems to be a bug; the game should not require a particular LAN for orbits near 180° inclination.

I downloaded your save and launched a satellite into retrograde orbit around Minmus,.  Just for spite, I waited until I was at about 280° from the reference direction revealed by OhioBob, and burned North so I would be ascending through the equator at that point. That made my inclination 179°  but that is close enough for the contract.  The contract completed.

[Kryxal]

Very nice catch, there ... I had a thought about this sort of thing, though.  I wonder if somebody could make a mod that would allow you to take a more "focused" look at contracts than that little drop-down.  Something like the Final Frontier or Scansat large windows would be nice, bonus points if you can select a specific contract and have the points broken down in evaluation.  Might turn it into a checklist for matching orbits, or for requirements with multiple conditions...