Delta-V required to get a reentry periapsis from stable orbit around Eve?

[MarkusF]

I'm just planning a trip to Eve consisting of an orbital station, an unmanned Eve lander, as well as an unmanned Gilly lander.

For the Eve lander, I'm trying to figure out, how much delta-V will be required to get from a circular 350km orbit to a safe periapsis for a reentry. However I'm not able to figure this one out by myself.

Would someone be able to tell me the number?

Oh, and is there a way for me to figure this out by myself, without flying there first?

Thanks in advance,

Markus

Edited May 6, 2015 by MarkusF

[Red Iron Crown]

The Vis-Viva equation is what you're looking for.

It gives orbital speed in 350km circular orbit as 2790m/s. If we aim for a 50km periapsis (not sure if this is good for Eve in the new aero), the speed at apoapsis is 2546m/s. So the delta-V required is about 244m/s.

[MarkusF]

Thanks a lot, that really helps me :-)

Took me a minute to figure out what the semi-major axis is, but now I got it.

[cephalo]

What the heck are you guys talkin about? Ugh, I'm going to have to know about all that stuff pretty soon I bet.