# Tag Info

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Could NASA put an artificial radar telescope satellite in geosyncronous orbit around Mars to help locate dangerous asteroids on a trajectory that would place them on a path to strike Earth? The "Could X happen?" or "Could X be done?" questions almost always collect comments like "it depends on how much (list of resources) you have." But in this case, ...

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You can find most of the information you need on the picture below which comes from Reddit. Crucially, if you add up the relevant lines, delta-V from Mars to Earth-Mars transfer is about 5.92 km/s. Assuming they produce the vacuum raptor (not planned for the very first starship missions) Starship will have an $I_{sp}$ around 380s, so by the rocket equation,...

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Putting the spacecraft id (-143205) into the JPL HORIZONS ephemeris system produces: TRAJECTORY: This trajectory is based on JPL solution #10, a fit to 364 ground-based optical astrometric measurements spanning 2018 Feb 8.2 to March 19.1 Trajectory name Start (TDB) Stop (TDB) -------------------------------- ----------------- ----------------- tesla_s10 ...

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The Mars 2020 rover uses a Radioisotope Thermoelectric Generator for power, so it doesn’t have any solar panels. It looks like the helicopter has its solar panel on top of the rotor. Flight vibrations will likely remove dust sufficiently. The helicopter may be able to remove dust from the rover for other reasons, but the main concern there is avoiding ...

3

There's several reasons why the JPL Mars Helicopter Scout would not be well-suited for this sort of mission: Its designed flight time is 90 seconds, once per day, which doesn't leave a lot of time for non-primary tasks. Even if dusting off solar panels was its only task, 90 seconds isn't a lot of time to do it. It is designed to fly a total of five times, ...

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Moving Phobos around takes an enormous amount of energy and as it does not have a magnetic field moving it to L1 wouldn't help anyway. Also, Phobos appears to be a rubble pile, so moving it is extremely difficult, it barely sticks together as it is and contains a significant amount of empty space. From Wikipedia: "The porosity of Phobos was calculated to be ...

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The sky crane engines were tested individually. This is common practice for small thrusters like the ones used in almost every launch vehicle and satellite, where test firings of the whole assembly are impractical. Other subsystem tests looked at the interaction between the engine exhaust and Mars' soil, for instance. Full-up tests are difficult. You need ...

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Somewhat counterintuitive, but Deimos would be a better choice than Phobos. Neither would be easy. Phobos has an orbital velocity of nearly 7,700 kph. Deimos, a bit better at about 4,860. To shoot dust off either moon, that's roughly how fast it would need to leave the moon. It's not just escaping the moon's gravity but escaping the orbit, and there's ...

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No one used XKCD? the interplanetary Cessna should give a good indication: https://what-if.xkcd.com/30/ The problem is how airships and especially blimps float. They are on average less dense than the air around them, and then float up to a region where the air is equally dense in average as the blimp. Unfortunately Mars has about 1% of the earths ...

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What is the closest distance SpaceX's Tesla Roadster (Starman) will ever be to Mars? I predict 0 meters. Musk will capture the Falcon-9 2nd stage adorned with his red Tesla Roadster, bring it to Mars and display it in front of SpaceX Mars headquarters in a similar fashion to the Falcon-9 in front of SpaceX Earth headquarters in Hawthorne. I think this is ...

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The New Horizons probe, if I read the Wikipedia article correctly, did not stay in its parking orbit for a full orbit. Less than 45 minutes after launch, it was already on its solar escape trajectory. But it did spend time on an orbital path that allowed it to get to the right position for the burn to escape velocity, consistently with the other answers ...

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To create a field like Earth’s, you need to invest about $10^{20} J$ into creating the field (see this SE Physics item). You might be able to save a couple factors of two, but that still leaves you needing something comparable to a year’s entire energy output of the United States. Interestingly, The mass of Phobos is about $10^{16} kg$, so the energy to ...

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Phobos is very small, 27km on its longest axis, so it wouldn’t do much of anything to affect Mars no matter where it is.

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You're going to love the Red Mars, Green Mars, and Blue Mars books by Kim Stanley Robinson. It's like history books on the colonisation of mars that fell through a portal back in time to today. Although fiction, and only one way to do it, they are nonetheless chock full of hard science.

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