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45

The Huygens was not capable of transmitting data directly to the Earth, instead Cassini relayed all communication. Therefore mission lifetime was limited by possible communication window from Titan surface to Cassini (which was orbiting Saturn, making only fly-by around Titan and departing the moon soon after the landing). Keeping Huygens alive until Cassini ...


33

The icy moons are of interest for exploration as part of the overall "follow the water" strategy of exploration that NASA (and others) have been exploring for some time. The "where else can water be found" is a major question in e.g. the US Planetary Science Decadal Survey (which is a community-driven consensus document which outlines the questions of ...


20

This book has a table with the energy budget for Huygens: Data relay system: 214 Wh Computer: 246 Wh Electric power system: 5 Wh Payload: 325 Wh Losses: 132 Wh Pre-separation checks: 50 Wh Total: 972 Wh for the designed mission: The batteries and all other resources were sized for a Huygens mission duration of 153 minutes, corresponding to a maximum ...


15

The motivation is the growing understanding, from the Voyager, Galileo and Cassini probes, that these icy moons (I'd throw in Enceladus) are geologically active with sub-surface oceans of liquid water, along with the realization (from studying the Earth's ocean vents and deep biosphere) that life can be sustained from the energy of geologic processes, not ...


11

Can Dragonfly make it to one of Titan's Lakes? tl;dr: Yes! It could be doable in 2-3 years. According to your linked document Dragonfly will use a Multi-mission radioisotope thermoelectric generator or MMRTG: The MMRTG design incorporates PbTe/TAGS thermoelectric couples (from Teledyne Energy Systems), where the TAGS material is a material incorporating ...


8

They plan to use some form of "site evaluation" to prevent tipping over: However, technology developments in the last two decades, notably the revolution in availability of multi- rotor drones a made possible by modern compact sensors and autopilots as well as the development of sensing and control capabilities for autonomous landing and site ...


7

Cassini's Imaging Science Subsystem produced images like this: which has a resolution of about 200 m/pixel. This is a near-IR image. In visible light, color enhancement can bring out some detail: In UV, the atmosphere is opaque again: The ISS spans IR, visible and UV light: Each camera is outfitted with a large number of spectral filters which, ...


7

From Cassini observations the methane-ethane mixture (with methane by far the largest component, maybe with some dissolved nitrogen) appears so pure that its absorptivity at the RADAR instrument's Ka-band frequency is quite low. That's how it could see so deep — not just 100 m, but 160-170 m. The paper The Bathymetry of a Titan Sea by Marco Mastrogiuseppe ...


7

The paper itself (I have access) says and shows that they are detecting the bottom of some lakes with their radar with a maximum depth of 105+/-6 meters. The radar reflection off the bottom is much fainter than off the surface, but still distinct and clear. The attenuation (17 dB/us) fits a mostly-methane composition (best fit 69% methane, the rest mostly ...


7

There are bacteria on Earth which get energy from hydrocarbons and oxygen. See for example this article. Many of them need oxygen which is not freely available on Titan. Some (thank's to @Calcutta for pointing this out) can use sulphate as an oxidising agent instead. However, as far as I can find out, essentially all the oxygen on Titan is in the form of ...


6

From Ulysse Carion's "subway map", the delta-V required is approximately: 9400 m/s to get from Earth's surface to low Earth orbit; 3210 m/s + 4500 m/s to intercept Saturn; 3060 m/s to intercept Titan; 660 m/s to get into orbit around Titan (at 1000km altitude to stay out of Titan's extremely deep atmospheric envelope). Thus, from Earth, you need a total of ...


6

Ruling out nuclear propulsion in the comments pretty much rules out electric thrusters of all flavours as well since the Juno mission is notable for pushing the limits of solar power, and only needs enough to operate sensors and radio link and is still 1/5 solar panels by dry weight (340 kg making 486 W, where electric demands for thrusters are in kW). For ...


5

Tl, dr: With some care, high surface winds can be avoided. They seem to occur only once per fifteen years or so as Titan is in equinox. If we avoid the storms, which would likely be done anyway to simplify landing the craft and taking off again, surface winds will not be a problem at all. From Wikipedia: Surface winds are normally low (<1 meter per ...


5

The International Astronomical Union is the most official source on this matter. Among other surface features on Titan the IAU recognizes 81 lakes (lacūs, "small dark plains with discrete, sharp boundaries") of 5km to 240km diameter (median 36km), and three larger seas (maria, "large expanses of dark materials thought to be hydrocarbons"): Kraken Mare, ...


5

This is to add to user30007's answer. I will write more later, but there are important points to add to this discussion, more than can be put into a comment. First, I've run across several articles that came up high on the list from a Google search that are full of errors. At the bottom of this post I'll give a couple of examples. Titan's surface ...


4

To my knowledge no mission has attempted to generate electricity from Titan/Saturn's magnetic fields (or Jupiter's for that matter), a list of missions to-date includes: https://en.wikipedia.org/wiki/Pioneer_11 https://en.wikipedia.org/wiki/Voyager_1 https://en.wikipedia.org/wiki/Voyager_2 https://en.wikipedia.org/wiki/Cassini%E2%80%93Huygens Planned ...


3

Newbie Titan researcher here! I was wondering about this same question, but there are a few papers that have since answered your questions. I'll summarize their findings below: TLDR: For an astronaut, the sunset would be quite underwhelming, much like being in a sand storm or thick smog. The sky will have no real change in its orange color. The Sun ...


2

As an alternative, there is the possibility of an oxygen-free metabolism. Let us look at some standard enthalpies of formation from the various Wikipedia articles for a few simple species $\text{H}_2 = 0$ kJ/mol (definition for elements in their standard state) $\text{CH}_4 = -74.87$ kJ/mol (Wikipedia) $\text{C}_2\text{H}_6 = -84$ kJ/mol (Wikipedia) $\...


2

Honestly, from what I can tell, not much consideration has been given to this issue. I checked the papers for these three Titan Probes; Dragonfly Titan MARE Titan Rover Concept (with inflatable wheels) Concerns with dust and dirt covering the probes came up 0 times. A report on the engineering challenges on Titan didn't even mention it. In fact the only ...


2

The key to navigation when in Saturn's moon system is Titan. Cassini flew by a vast numbers of targets while barely spending any fuel. This was accomplished by a gravity assist scheme where the key component is successive flybys of Titan for every orbit. Titan is relatively massive, so it can alter your probe's trajectory dramatically. Exactly how it's ...


2

Delta-v map is good enough for direct transition trajectories. If you are interested how the real space missions to Titan (or at least the real designs) work, the picture will be some different. First difference - when we leave the Earth's orbit, we don't need to burn rockets so much. We can borrow most of remaining delta-v by gravity assists. Earth and ...


2

Cassini's Visual and Infrared Imaging System produced these global views of surface chemical compositions (determind via spectrometry), with infrared light. The colors are not colors that would becseen by the eye but markers for different chemical composition. Orange represents hydrocarbon dunes, blue and purple colirs suggest more water ice. Image via ...


1

The Cassini-Huygens mission was a fantastically successful flagship-class mission to the Saturn system, with the Cassini spacecraft spending 13 years in orbit there and delivering the Huygens probe that made the first successful hard-surface landing in the outer solar system. The results are so voluminous, and cover so many different aspects of the Saturn ...


1

For a start read the Wikipedia article. The next step would be the more than 100 references at the bottom. Many links to NASA, JPL and ESA documents.


1

There seem to be two different kinds of liquid system operating simultaneously on Titan: one of these is the system of hydrocarbon lakes you are thinking of, the other though is much larger and underneath the visible surface crust those lakes rest on which, itself, is actually water ice that is so hard due to the extremely low temperatures (94 K) that it is ...


1

Underground liquid methane has been proposed as a source of the liquid in the methane-rich lakes on Titan, but it is not an ocean. Rather, as is summarized here it penetrates pores in the icy solid, similar to water in the pores of Earth's rock below the surface. The hydrocarbon liquid is not proposed to interact with the water (or water-ammonia) ocean ...


1

Following is a block quote from How to Get an Atmosphere by Peter Tyson Saturn's moon Titan belongs to a very select club within the solar system. It is one of only four "terrestrial" planets or moons—those with solid bodies, as opposed to those made largely of gas, like Jupiter and Saturn—that has a substantial atmosphere. The other three that ...


1

It would have to be vastly different to earth physiology but there are exothermic chemical reactions possible with compounds found on Titan. This may well not be the only hurdle though. For example without having a solvent for the redux reaction and a functional group for what ever the analog of enzymes would b in this system: using this energy would be ...


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