Sun-Synchronous Orbit Around Mars

[krashkart]

(For the Non-Mathematician) :hide:

How would I go about putting a vessel into sun-synchronous orbit around Mars? :idk:

 

[Hmuda]

EDIT: nvm

 

[Star Voyager]

(For the Non-Mathematician) :hide:

How would I go about putting a vessel into sun-synchronous orbit around Mars? :idk:

I just flew a less-than-5-minute-mission with a Legacy DG Mk. III for you and the answer is a highly elliptical polar orbit (my Ecc. was ~ 0.42).

 

[Ajaja]

How would I go about putting a vessel into sun-synchronous orbit around Mars? :idk:

Look at "Example: calculate the inclination for a sun-synchronous polar orbit" in Doc\Technotes\gravity.pdf.
Mars sun-synchronous polar orbits with ecc=0:
Alt=100km; Incl=95.75deg.
Alt=200km; Incl=96.09deg.
Alt=300km; Incl=96.44deg.
Alt=400km; Incl=96.79deg.

 

[N_Molson]

There's an easy way to do that without having to dig into Maths.

What's a geosynchronous orbit ? It's a near-circular orbit, with an equatorial inclination near 0°, and with T = sidereal day ( 86164 seconds).

Geos means "Earth", in ancient Greek.

So, a "marsynchronous" orbit would use the same principles. For that, we need to know the duration of a sideral day on Mars. Thanks Wikipedia :

"The average length of a Martian [ame="http://en.wikipedia.org/wiki/Sidereal_day"]sidereal day[/ame] is 24h 37m 22.663s"

23 seconds will be ok, we don't need that much precision !

24*3600+37*60+23 = 88643 seconds

Now search for a circular (Ecc ~= 0), equatorial (Inc(ref EQU) ~= 0) orbit around Mars with T = 88643 sec.

That should work, unless I missed something obvious, which is possible :lol:

Edit : obviously, I didn't read carefully enough the topic, which was about Sun-synchronous orbit :beathead:

Edit2 : replace "marsynchronous" by "areosynchronous". It makes sense : Ares was the Greek god of War (Mars was the Roman one).

 

[krashkart]

Look at "Example: calculate the inclination for a sun-synchronous polar orbit" in Doc\Technotes\gravity.pdf.
Mars sun-synchronous polar orbits with ecc=0:
Alt=100km; Incl=95.75deg.
Alt=200km; Incl=96.09deg.
Alt=300km; Incl=96.44deg.
Alt=400km; Incl=96.79deg.

Thank you, Ajaja. I'll kludge together a scenario and give it a whirl. :tiphat:

Edit : obviously, I didn't read carefully enough the topic, which was about Sun-synchronous orbit :beathead:

It's all good. You earned an A+ for effort. :thumbup: [EDIT] Actually, now that I think of it you may have just helped with another thing I'd been thinking about. :lol:

 

[tblaxland]

So, a "marsynchronous" orbit would use the same principles.

FWIW, the prefix "areo-" is normally used for the Mars equivalent of "geo-", eg, "areosynchronous". Mars is the Roman god of war, Ares is the Greek god of war and "geo-" comes from the Greek for Earth. Likewise "selen-" is used for the Moon, eg, "selenography".

 

[krashkart]

Okee-doke, launched a DG from Olympus base on a heading of 345 and it will be hitting ~400km in twenty minutes or so. It wasn't a perfect launch but I managed equatorial inclination of 98.71 on this first try.

Took off to the great white north...

With enough practice I'll nail the inclination the first time every time.

 

[tblaxland]

With enough practice I'll nail the inclination the first time every time.

I recommend [ame="http://www.orbithangar.com/searchid.php?ID=2802"]Launch MFD - v 1.3.3 BETA for Orbiter 2010[/ame] for that.

 

[krashkart]

Thanks. I'll give it a whirl. :tiphat:

 

[czechspace]

How I can access the file *\Doc\Technotes\gravity.pdf ?

 

[francisdrake]

If you have Orbiter installed, it is in the Doc folder.

Assuming your installation folder is called "Orbiter", it is in
Orbiter\Doc\Technotes\gravity.pdf

 

[czechspace]

If you have Orbiter installed, it is in the Doc folder.

Assuming your installation folder is called "Orbiter", it is in
Orbiter\Doc\Technotes\gravity.pdf

Thank you, it is helpfull. I will follow your instruction.

 

[Boxx]

Don't forget to check the box Parameters > Perturbations > Nonspherical gravity sources
(because Sun-synchronous orbits are permitted by the fact that Mars, like Earth, is not spherical)