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On average how much deltav does it cost to get into a Moho orbit?


Nerbal The Second
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Moho is at a pretty steep inclination so your plane change can cost a lot, it all depends on where exactly Kerbin and Moho are in their orbit. In general if you have to spend more than around 4.5K deltaV for transfer burn from LKO plus orbital insertion to low Moho orbit I would wait for the next transfer window, they come by fairly frequently for Moho. You need about 2.5K to get into low Moho orbit from your transfer, and you probably want to take some extra for plane changes since you're liable to end up at a big inclination, although if you're landing you can probably just skip that step. So add 2.5-3K to whatever burn will get you there (which can be anywhere from 800 to 3K+, but you can find that out before leaving by creating the node for it) and you should be safe.

That's excluding what you need for landing which adds another 1K with a bit to spare.

Moho is pretty much the one planet I always do a complete test run for because it has betrayed me a few times with the amount of deltaV needed to get into a nice orbit. The fact that it has no atmosphere or moons means that there is no way to get any 'assistance' on slowing down, it all has to come from the engines and it also has to be delivered in a fairly short time, a high TWR is recommended. Aiming for a polar orbit can be cheaper, so if you're going to land that might make more sense.

Gravity assists from Eve can change the whole game but if you're going for that you don't need my help! :)

 

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On 2/4/2022 at 7:18 PM, Beamer said:

Moho is at a pretty steep inclination so your plane change can cost a lot, it all depends on where exactly Kerbin and Moho are in their orbit. In general if you have to spend more than around 4.5K deltaV for transfer burn from LKO plus orbital insertion to low Moho orbit I would wait for the next transfer window, they come by fairly frequently for Moho. You need about 2.5K to get into low Moho orbit from your transfer, and you probably want to take some extra for plane changes since you're liable to end up at a big inclination, although if you're landing you can probably just skip that step. So add 2.5-3K to whatever burn will get you there (which can be anywhere from 800 to 3K+, but you can find that out before leaving by creating the node for it) and you should be safe.

That's excluding what you need for landing which adds another 1K with a bit to spare.

Moho is pretty much the one planet I always do a complete test run for because it has betrayed me a few times with the amount of deltaV needed to get into a nice orbit. The fact that it has no atmosphere or moons means that there is no way to get any 'assistance' on slowing down, it all has to come from the engines and it also has to be delivered in a fairly short time, a high TWR is recommended. Aiming for a polar orbit can be cheaper, so if you're going to land that might make more sense.

Gravity assists from Eve can change the whole game but if you're going for that you don't need my help! :)

 

You should also make sure you meet Moho almost exactly at its periapsis. If you’re coming in from an orbit with a lower Pe than moho’s orbit, the orbital insertion cost will be dramatically higher. Even just a little bit of error can increase the cost by a few km/s. 
If you line everything up perfectly, you should expect an insertion burn in the realm of 2 km/s of dV, plus the 2.5k you spent leaving LKO.

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A bit late, but the best Moho transfer from Kerbin's going to be at node intersection, aiming for Moho PE.  Just meet the orbit, don't worry about meeting the planet first time around.  You'll be able to fix your inclination cheaper, further out, and combine it with the ejection burn.  Once you're at your PE, bring your AP down so the next orbit is a rendezvous, you'll then need less delta-v on the capture burn.

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