I'd like to see a mission that includes an orbiter and several small penetrators... Well, something like the Magellan design. It seems that most people don't like the penetrator idea, especially after the Deep Space 2 failure, but I'm a big fan of it. And why not? It's easier to build and test, and setting several penetrator increases the chance of success.

Think about the following designs:

1. Mars Orbiter + Deep Space 2 - like penetrators. No parachute system, the penetrators hit the ground. Analysis of the soil, possible biological experiments..

2. Mars Orbiter + Mars Descent Probe and a penetrator. The descent probe enters the atmosphere, a parachute deploys. Mars Descent Imager possible. Imaging, analyzing the atmosphere+direct telemetry to the orbiter. After that the parachute system is ejected, and the penetrator makes a crash landing. Analysis of the soil, possible biological experiments.

3. Mars Orbiter + Mars Descent Probe + baloon probe. The descent probe enters the atmosphere, the parachute deploys. The baloon is inflated and the probe makes a lot of atmospheric measurments. Baloons have been discussed here before.

Hope this thread is not going to be treated as the most stupid idea of the year...

Well in a Jaxa publication they mentioned they want a Mars (Nozomi Refly) mission for 2015. But they are not quite sure yet how it will look like. But since they are finally making huge progress with their penetrator technology they are thinking to include penetrators with or without a lander on a Nozomi 2.
So at least one agency is thinking about it.

Penetrators are a one-shot deal with a high risk of failure. They also need to be relatively high mass to penetrate deeply enough to find something of interest. Given how extraordinarily valuable each gram of cargo delivered to the surface of Mars is, I would say the mass of a penetrator (3.5 kg each for the DS2 version) would be far more useful in the form of an additional instrument or battery for a rover or orbiter. (or drill)

In fact, I would say that the MER success has greatly reduced the likelihood of a penetrator mission to Mars. Balloons are a very cool idea though, except for the problem of getting them inflated and bouyant in a wimpy atmosphere.

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