Group2 19-1 Week1

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Week 1 logbook

Mars rover edit for Europa (Jupiter's moon, not the continent)

Problems statement and objectives
- In the 2020s (the exact date is to be determined), NASA intends to send a mission to Jupiter’s moon Europa where a spacecraft will orbit around Europa with the ultimate goal of determining whether it would be able to sustain life. If this mission is found successful, the next logical step is to send a rover (much like the ones forming the majority of the current martian population) to Europa to take a closer look at Europa’s surface. However, Europa and Mars are significantly different planetoids. What changes would have to be made to the latest Mars rover - Curiosity - to make it suitable for a mission to Europa?

Who are the users?
- NASA
  - Project aids them in going to Europa
- Scientific community
  - We learn more about planetoids in our solar system
- Humanity
  - We may find a new habitable planet in our solar system to help distribute the human population load on Earth

What do they require?
- NASA requires a detailed dissertation on what changes need to be made to Curiosity to send it to Europa

Approach, milestones and deliverables
- Investigate how Curiosity is adapted to Mars -> Find out how Europa differs significantly from Mars -> Adapt Curiosity to work on Europa
- Deliverables are certainly requirements for Curiositwo, and hopefully a digital model of what it looks like

Who is doing what?
- Divide in three parts
  - Research equipment
  - Driving components (energy, wheels, etc)
  - Communication and autonomy

SotA: literature study, at least 25 relevant scientific papers and/or patents studied, summary on the wiki!

Mars:
- Surface:
  - Chemistry
    - Iron, magnesium, aluminum, calcium and potassium in crust
  - Solidity
    - Sand and dirt
    - Only frozen water
- Seismology:
  - Stationary Core
  - Tectonics
  - Volcanoes and canyons
- Atmosphere:
  - Makeup
    - CO2, N2, Ar
  - Sandstorms
  - High temperature differentials
- Dangers:
  - No magnetosphere
    - Solar wind
  - Sandstorms
Europa:
- Surface:
  - Chemistry
    - Largely frozen (salt) water
    - Reddish brown material in the cracks, likely salt and sulfur compounds
  - Solidity
    - Icy layer with large cracks (1-2 km wide to 100s of kms long) and tall ridges
    - Could be convecting slowly
    - Possibly liquid water; floating?
  - Sub-Jovian side is smoother than anti-Jovian??
  - Penitentes
- Seismology:
  - Core
    - Iron core, rocky mantle, saltwater or slushy second mantle, icy crust
  - Tectonics
    - Close proximity to Jupiter creates changing tidal forces which flex Europa as it orbits Jupiter, creating tectonics in the icy crust.
- Atmosphere:
  - Thin Oxygen atmosphere
  - Cold AF
- Magnetosphere
  - Jupiter disrupted by Europa; electrically conductive fluid (e.g. salt water) beneath the surface
  - (Investigate strength)
- Dangers:
  - Jupe-Jupe?
    - Gravity is complicated because due to Jupiter, the net gravity on Europa is not uniform; watch out with toppling the rover
- Previous explorations
- Chaos Terrain
  - Conamara common example
    - Is, however, very young -> few million years
      - Pre-conamara terrain?
    - Very small
  - Tectonic terrain that has been jumbled up like a puzzle
    - ‘Rafts’
  - Upwellings of ‘magmas’?

Find out what we would want to know about Europa; what findings we would need to do:

https://www.pnas.org/content/pnas/111/35/12628.full.pdf

A bit more general:

https://s3.amazonaws.com/academia.edu.documents/39166815/542b29350cf29bbc126a8004.pdf?response-content-disposition=inline%3B%20filename%3DThe_Geology_and_Habitability_of_Terrestr.pdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWOWYYGZ2Y53UL3A%2F20190907%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20190907T081223Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=053fed57f352135b995eab367cd850e35ec009cc20d4be763217f5b847521a91

Water occasionally resurfaces in pools due to tectonic movement; forms pools (chaos terrain). Liquid water thus available.

Jupiter is 5.2 times farther from the sun than earth, and thus on average so is Europa. By the inverse square law, Europa will then receive 5.2^2 times weaker light than the earth: 1000/27=36.9 W/m^2

Probably not too much UV as it is further away from the sun than earth and Earth does not supply UV. But… Search for possible UV (and other radioactive) sources

Atmosphere altogether?

Presence of biogenic elements is little known, important to research

http://scifunam.fisica.unam.mx/mir/europa.pdf

Icy spikes equator (penitentes)

https://www.geo.umass.edu/courses/geo892/HobleyEtAlEuropaPententes2018.pdf

(For comparison, the article is not really clear about what the penitentes look like: [1]) Penitentes form due to impurities in ice or snow layers that cause lensing effects, causing areas of the snow layer to sublimate more quickly than others. The result is loose spikes standing around. Conditions on Europa allow for the growth of penitentes, which are estimated to grow up to 15 m. Observations of reflectivity indicate rough areas that may be penitentes. Furthermore, this is likely to occur on a timescale shorter than other erosion processes. For a rover, penitentes may prove to be difficult terrain to traverse. However, due to the specific circumstances under which penitentes form, they can possibly reveal information not readily available at the top layer of Europa’s crust. Life in penitentes?

Look at Enceladus - Saturn’s moon - for water sprays

More something for Europa Clipper to look at. If Europa does spray its water out like Enceladus, that’s convenient to research because it allows us to determine some of the chemical makeup of Europa before landing on it. That information, however, is best used to determine how to get onto the surface and what to do there, rather than determine it when we’re already on the moon.

https://solarsystem.nasa.gov/moons/saturn-moons/enceladus/in-depth/

Type of icy terrain

To an extent, this is difficult to know, because we don’t have pictures of Europa at a scale that would reveal what the top layer of Europa’s crust looks like. Pictures of 10 m/pixel resolution are considered very high resolution, and only small spots of Europa have been analysed in such detail.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050175937.pdf

Europa is largely smooth, with slopes no steeper than 5 degrees, except for craters and ridges, where slopes can go up to 15 degrees.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009GL039062

Probably Europa Clipper will reveal more.

	Curiosity	Mars 2020
Length, width and height	Respectively 3, 2.7, and 2.2 meters	Respectively 3, 2.7, and 2.2 meters
Mass	899 kilograms	1050 kilogram (The combination of the larger instrument suite, new Sampling and Caching System, and modified wheels makes Mars 2020 heavier than Curiosity.
Wheels and legs	6 wheels	6 wheels, each with individual motor. The two front and two rear wheels also have individual steering motors. The wheels are more robust, bigger in diameter and made of thicker aluminium
Cameras and X-ray spectrometers	Hazard Avoidance Cameras (HazCams), Navigation Cameras (NavCams), Mastcam, ChemCam, MAHLI, MARDI	Hazard Avoidance Cameras (HazCams), Navigation Cameras (NavCams), CacheCam, Mastcam-Z, SuperCam, PiXL, WATSON
Top speed	140 meters per hour	152 meters per hour
Energy consumption	Slightly over 100 Watts	Less than 200 Watts
Tilt	The rover can withstand a tilt of at least 50 degrees in any direction without overturning	The rover is designed to withstand a tilt of 45 degrees in any direction without tipping over. For added protection and safe driving, the rover drivers avoid terrains that would cause a tilt of more than 30 degrees
Technology toolbox		The rover can sample and cache (=temporary memory) minerals. To do so, The rover has a new coring drill to collect samples. The samples are then sealed in tubes and placed on the surface of Mars
Robotic arm on the front	Curiosity studied samples collected onsite, using its onboard laboratory	Mars 2020 will collect rock cores. Mars 2020 needs to collect rock core samples and save them for possible future study by scientists. Mars 2020 has a larger hand, or 'turret', and its new functions and new sciencs tools mean it must accomodate this larger turret. It has a coring drill and two science instruments, plus a color camera for close-up surface inspection and 'selfies' for engineering health chechups
Operation software		Team still working on new software. More independence. More effective autonomous use of electrical power

Sources:

https://mars.nasa.gov/msl/mission/rover/

https://mars.nasa.gov/mars2020/mission/rover/

Autonomy of Rovers

Curiosity: 376 days after the landing of Curiosity on Mars it completed the first drive in which it used autonomous navigation on unknown ground. This addition to Curiosity’s array of capabilities uses software that engineers adapted to this larger and more complex vehicle from a similar capability used by NASA's Mars Exploration Rover Opportunity, which is also currently active on Mars. In May 2016, NASA began using an autonomous targeting system, called AEGIS, that allows the Curiosity rover’s cameras to automatically detect preferable terrain to sample. Mars 2020: Also, engineers have added a "simple planner" to the flight software. This allows more effective and autonomous use of electrical power and other rover resources. It allows the rover to shift the time of some activities to take advantage of openings in the daily operations schedule.

https://www.jpl.nasa.gov/news/news.php?release=2013-259

https://www.wired.com/story/curiosity-rover-autonomy/

https://mars.nasa.gov/mars2020/mission/rover/body/

ESA JUICE mission

The ESA plans to send a probe to Jupiter to perform flybys on Callisto, Ganymede and Europa, three of Jupiter's moons. Even though this mission focuses on Callisto and Ganymede, two Europa flybys are also expected to be made. All in all, during the entire mission, the spacecraft is planned to have a total of 25 gravity assists, mostly by Jupiter, and flybys, mostly past Callisto and Ganymede, but also the aforementioned two past Europa. The actual spacecraft that will be used for this mission is one that is engineered towards the very large distance from the sun, the utilization of solar energy, and the harsh levels of radiation around Jupiter. While the science objectives for Callisto and Ganymede differ from those for Europa, those for Europa will focus on finding the composition and structure of this planetoid. This means that JUICE will be looking for molecules that could contribute to the formation of life, but also at how the surface features of Europa could have come to be. Not only the surface features will be considered, however, as JUICE will also try to look at the composition of materials of Europa, other than the water-ice.

Sources:

https://sci.esa.int/web/juice/-/50068-science-objectives

https://sci.esa.int/web/juice/-/50069-spacecraft

NASA Europa Clipper mission

NASA's Europa Clipper mission, similar to ESA's JUICE mission, plans to investigate whether Europa has the right conditions for life to form and also thrive there. In contrary to ESA's JUICE mission, though, NASA's Europa Clipper mission will solely focus on Europa. In this mission, a spacecraft will also be brought in orbit around Jupiter. By means of flybys, the spacecraft will perform detailed observations of Europa's characteristics. As per NASA's given list of onboard instruments, these observations will include:

high-resolution images made from the surface, using cameras
determination of surface composition, using spectrometers
determination of thickness of ice layer and search for any lakes under the surface, using an ice-penetrating radar
determination of depth and salinity of eventual oceans under the surface, by using a magnetometer to measure Europa's magnetic field strength and direction
search for heat signatures in the frozen surface, using a thermal instrument
search for water particles in Europa's atmosphere

Where ESA's JUICE mission is expected to only make 2 flybys past Europa, NASA's Europa Clipper mission is expected to make 45 flybys, some even as close as only 25 kilometers above the surface.

Sources:

https://www.nasa.gov/europa/overview/index.html

NASA Europa Lander mission

Even though this mission is, at this moment, only a concept, NASA is also planning to put a lander on Europa itself. This mission does not have a launch date yet, but, with this mission, NASA plans to go beyond even the scope of the Europa Clipper mission and investigate the surface of the moon from the very surface itself. In this concept, NASA plans to dig about 10 centimeters into the surface, and collect samples from there. NASA argues that this is a depth at which the delicate chemical compounds, necessary for life, are sufficiently shielded from the harsh radiation around Jupiter. These samples are then analyzed by the lander's onboard laboratory. The lander is expected to furthermore be equipped with a microscope, a camera, and a seismometer for the detection of seismic activities on the moon.

Sources:

https://www.jpl.nasa.gov/missions/europa-lander/

Unused links

About Europa

https://solarsystem.nasa.gov/moons/jupiter-moons/europa/in-depth/

Europa, the ocean moon, search for an Alien Biosphere

https://link-springer-com.dianus.libr.tue.nl/content/pdf/10.1007%2Fb138547.pdf

Content: Mostly information about the current knowledge of Europe, it’s tides and the possible life on the moon. Unmasking Europe, the search for life on Jupiter’s ocean moon

https://link-springer-com.dianus.libr.tue.nl/content/pdf/10.1007%2F978-0-387-09676-6.pdf

Content: More general information about Europe.

About Jupe-Jupe

https://solarsystem.nasa.gov/planets/jupiter/overview/

NASA Europa Lander mission

https://en.wikipedia.org/wiki/Europa_Lander_(NASA)

Articles about Mars: