Discussion Your Venus/Mars mission concepts/proposals

[ISProgram]

So a while back I decided that the storyline for my fiction space agency (IPSA) was lacking some unmanned planetary science missions, so I started thinking up proposals.

One of those resulted in VESPA (currently the Venus Environmental Surveyor Preliminary Assessment), an ambitious mission which is set to perform in situ measurements of the Venusian environment both from an orbiting mothership and a long-lived balloon platform.

The spacecraft is currently listed in internal launch manifests for a launch on December 10, 2032, aboard an Aquarius 104 launch vehicle (which, as you might know, is still WIP) At the moment, there are no plans to make a addon from this proposal, so it shouldn’t matter anyway. Illustration below is of the baselined spacecraft.

This thread is here so that anyone can discuss their fictional mission proposals to Venus/Mars, so I'll explain more detail for VESPA in later posts (and better pictures, too!).

 

[K_Jameson]

The FOI proposal for Venus, that was actually launched towards the planet during one of the Orbiter Live Missions broadcasts of 2013, is the "Efesto" spacecraft.

This can be the chance for a brief explanation of the story of this mission.
Efesto, previously named only "Venus Atmospheric Probe" was born as part of the ambitious Galileo II spacecraft. At some point in the development of that mission, was decided to split the Galileo II and the Salviati Europa minilander in two distinct missions, and to launch both in a VEEGA trajectory towards Jupiter. The slot on the Jupiter orbiter left empty by the Europa lander was filled with an atmospheric probe, that would be released during the Venus swing-by.
Later in the development, Galileo II and Salviati was reunited for a direct, single Hohmann launch to Jupiter with a Jarvis M superheavy rocket, losing in the process the Venus encounter.

The atmospheric probe, already completed, remained without a carrier spacecraft. Thus was rapidly created a small and very essential cruise stage just for deliver the probe at his destination. Quickly became evident that the designed launcher (Neptune-1) can deliver a far larger payload to the planet, and thus was decided to make the mission - christened "Efesto" after Hephaestus, the Greek god of the fire - a little more ambitious, drawing a true, medium-sized Venus orbiter, that also would be the base for future spacecrafts.

The launch was performed on Orbiter Live Missions; when the broadcasts discontinued, the opportunity to show the Venus arrival, some months later, was lost. The addon was never released but is in my plans for the next months.

As stated, the Efesto orbiter platform is the base for subsequent spacecrafts. The Shakespeare Uranus Orbiter (check the Uranus/Neptune thread) is substantially an improved and RTG-powered Efesto, and I have at least one more concept based on the Efesto bus: the MARTE space probe, that I'll explain later.

---------- Post added at 12:54 PM ---------- Previous post was at 11:14 AM ----------

Regarding your proposal, I think that is interesting (somewhat analogous and complementary to Efesto). I'm curious about the scientific payload. The solar panels can be drastically reduced.

 

[ISProgram]

Thanks!

Regarding the solar arrays, this was the baselined spacecraft, but the design has actually changed by alot (I'll get to that later).

The larger-than-need solar arrays were present because I considered that extra power generation would be needed for the balloon platform while en route to Venus, and also because when the orbiter was to be aerobraking to a circular orbit, the solar arrays would produce more drag and help stabilize the probe (many Mars orbiters are actually designed with aerodynamic properties/configurations so they can dip into the atmosphere, e.g. MAVEN, MGS).

Magellan and VEX found out first hand that aerobraking at Venus needs to be done very cautiously.


And since this is a Mars mission proposal thread too:

An old project I was doing, which recently got rebooted. I'll explain this one after VESPA, but it is was called TSL (Terrestrial Science Laboratory).

 

[TMac3000]

I had a Mars concept in mind once-upon-a-time. See this thread.

It got kind of poo-poooed, and maybe rightfully so, but it was really ambitious and used only present-day tech

 

[Nicholander]

Interesting concept, ISProgram!

I've been having this idea floating around in my head for quite a while, but I haven't really done anything about it, It's called PADSL (Phobos And Deimos Science Laboratory), by the way. It would launch on a direct Hohmann trajectory to Mars, and would use its engines to get into an elliptical orbit around Mars, (Into the same plane as Phobos and Deimos) and use aerobraking to reduce it's apoapsis to that of Deimos, and the from there intercept Deimos.

Then, it would land on Deimos, and stay there for a few months doing science experiments and such. After that it would leave Deimos and do the small 745 M/s burn to intercept the larger Martian moon Phobos. And, like what it did on Deimos, do science and such. And after that, it's mission would end.

And I haven't quite decided on the launch vehicle yet, but I've narrowed it down to the Jarvis and M-II. I'd prefer the Jarvis, but it can't launch directly to the ecliptic, though I'm not sure how much that would decrease the payload capacity.

 

[K_Jameson]

Regarding Mars, this is an early version of my MARTE space probe, based on the Efesto bus.



MARTE stands for: MArs Reconnaissance TElescope and is a concept for a FOI analogous for the NASA Mars Reconnaissance Orbiter. It's a somewhat simpler spacecraft with only one main instrument, a 48 cm reflector that is the same instrument used on Galileo II as Narrow Angle Camera. Main purpose of MARTE is high-resolution mapping from low mars orbit, in preparation for future missions (mars sample return and, possibly, manned missions).

In a more recent iteration of the project, the acronym was modified in MArs Relay and TElescope and the probe has gained another main mission, that is communication relay for the other spacecrafts orbiting mars and on the martian surface. For this purpose, the 2.9 fixed HGA (Efesto heritage) would be replaced with a larger umbrella-like 4 or 4.5 meters antenna, for a far larger bandwith, and the solar arrays would be increased in support of the enhanced communication system.

---------- Post added at 03:36 PM ---------- Previous post was at 03:34 PM ----------

I'd prefer the Jarvis, but it can't launch directly to the ecliptic

why not?

 

[Nicholander]

I like the idea of MARTE, though I'd prefer something more like the first Hi-res imaging of Mars that you described in your first paragraph. But anyway, what do you think of my PADSL concept? (I really have to think of a better acronym for that)

EDIT: It can't launch to the ecliptic because it can only launch from Cape Canaveral or Capo Passero, both are above 23.5 degrees in latitude.

 

[K_Jameson]

PADSL is a really interesting concept, similar to Phobos-Grunt. I'm dubious that such a flight plan can work, because during the interception of Deimos you has an high relative velocity and thus an high delta-V is required for slowing down and land on the moon. Remember that these moons are VERY small and their gravity is ludicrously small. Further calculations are needed to ensure the feasibility of your concept.

---

You can absolutely launch to the ecliptic from KSC. You just have to choose the right time to launch. In Orbiter Live Missions, Galileo II was launched from KSC in a direct Earth-Jupiter hohmann across the ecliptic, and Efesto was launched in an Earth-Venus hohmann from Capo Passero that has an even higher latitude :thumbup:

In fact, is really difficult to launch outside the ecliptic, because of the component of the high orbital velocity of the Earth around the Sun, that is far higher than the launch velocity of every spacecraft. For diving significatively above or under the ecliptic, you need the gravity assist of a giant planet, as Ulysses did with Jupiter.

 

[Nicholander]

I do know that Phobos and Deimos have practically no gravity, but perhaps it'd be better to go to Phobos first, and then Deimos. Also, according to this website, you need 745 m/s of delta-v to go from the surface of one Martian moon to the surface of the other.

And where Galileo II and Efesto launched during an equinox or something? Because I thought latitudes above 23.5 degrees never aligned with the ecliptic.

EDIT: By "Launching to the ecliptic" I mean that when you reach LEO that Orbit MFD says your inclination to the ecliptic is zero, or at least very close to zero. And I think you have to have that because when I use IMFD (I don't know how to use TransX), the burn vector for Trans-[Insert Planet Here]-Injections are always not aligned with my orbit's prograde, sometimes up to 90 degrees away. So, either I'm terrible at using IMFD, or you really do have to be lined up with the ecliptic.

 

[ISProgram]

I like the idea of MARTE, though I'd prefer something more like the first Hi-res imaging of Mars that you described in your first paragraph. But anyway, what do you think of my PADSL concept? (I really have to think of a better acronym for that)

EDIT: It can't launch to the ecliptic because it can only launch from Cape Canaveral or Capo Passero, both are above 23.5 degrees in latitude.

Well, can't do any detailed response at the moment, but I've read somewhere that the delta-V cost for getting to one of those Martian moons (think it was Deimos) is actually quite high; higher than escaping Mars entirely. Not sure though. :/

There's a Discovery mission proposal called PADME (Phobos And Deimos & Mars Environment), if it helps. But I feel that the spacecraft will need a lot of delta-V (and time). Though I suspect you already accounted for this.

I'll definitely like to see the more detailed mission profile, I'm intrigued.

:ninja:

 

[Nicholander]

Well, can't do any detailed response at the moment, but I've read somewhere that the delta-V cost for getting to one of those Martian moons (think it was Deimos) is actually quite high; higher than escaping Mars entirely. Not sure though. :/

Like I linked to in my page (This link), you'd need 745 m/s of delta-v to go from the surface of one Martian moon to the surface of the other.

 

[K_Jameson]

Like I linked to in my page (This link), you'd need 745 m/s of delta-v to go from the surface of one Martian moon to the surface of the other.

The problem is reach the surface of the first moon from the elliptic initial orbit. When an elliptic orbit intersects a circular one, the difference of velocity at the intersection can be quite high. For the Jupiter moons at least, it is prohibitively high. In case of Earth, the difference in velocity from a GTO and a GEO orbit is of several km/sec. I'm not sure for Mars; I never studied a similar mission.

 

[Nicholander]

Well, I'll try to figure out how much delta-v you'd need from that orbit in Orbiter and tell you what happens.

 

[K_Jameson]

Try with the Delta Glider! :yes:

 

[Nicholander]

I've just finished, and though I didn't do it with the Delta Glider (I did it with the UCGO Shuttle-A), it's about 550 m/s of delta-v. So, say about 1 km/s of delta-v to get into the very elliptical orbit (use aerobraking to get it's apoapsis down), 300 m/s for course corrections getting to Mars, the 550 m/s for intercepting Phobos, and the 745 m/s for getting to Deimos from Phobos, and you get 2595 m/s of delta-v. That's quite a lot if you ask me.

 

[K_Jameson]

You need a quite large probe.
Galileo II has over 3 km/sec of delta V, but it is a 12 tons spacecraft!

A large probe or a multi-stage probe: you can imagine a cruise stage, only for the MOI, the aerobraking and the others orbital corrections, and a separate lander for the Deimos descent, the Deimos-Phobos trip and the Phobos final landing. This approach can greatly increase the combined delta-V of your spacecraft.

 

[Nicholander]

Well, correct that to Phobos-Deimos trip, because I did that for intercepting Phobos, not Deimos. Sorry for not making that more clear.

Also, Galileo II was made for exploring Jupiter, so PADSL will not RTGs and will have a smaller antenna.

 

[K_Jameson]

My citation was only for reference.
Also, RTG are lighter than solars in outer solar system...

 

[Nicholander]

Oh, sorry. I didn't mean to be rude or anything. And yes, I know why Galileo II had RTGs, as solar panels receive 4% of the energy they'd get at Earth, but I'm talking about at Mars range, so solar panels would be used in PADSL. But, for the sake of comparison, how much mass does Galileo II's RTGs have, and how much would solar panels that generate the same amount of power at Mars' distance weigh?

Also, does that 12 tonnes include or exclude the fuel of Galileo II? If it does include the fuel, then how much did it's fuel weigh?

EDIT: Using NASA's Trajectory Browser, I figured out a 2024 launch window that PADSL could launch on, and it says that orbital insertion would only be 571 m/s, and since that sounds too low to be a circular orbit, I'll assume it mean a highly elliptical orbit just below escape velocity. So that reduces the required delta-v budget by about 400-500 m/s. This is it: Link

 

[K_Jameson]

I haven't a precise figure of the weight of the Galileo II's RTG, only of its power output, estimated on 1.32 kW. The total mass of Galileo II is 12,731 Kg, of which:

Spacecraft: 4,238 Kg
Spacecraft fuel: 7,900 Kg (N2O4/MMH)
Europa mini lander: 205 Kg (including fuel)
Europa lander booster: 388 Kg (including fuel)

These are some of the "press release" images realized for the Orbiter Live Mission broadcast. I hope that can be useful:







Sorry for the OT!!!