Elemental Factfile: Titanium

The shift to use fully compostable materials for construction may help save our planet by eliminating the masses of waste non-recyclables produced by the construction industry. Unlike the fossil fuel derived and energy intensive materials that are used for building fabrication, these new 3D printable biopolymers can be reused and eventually composted.

So, when will we have 3D printed skyscrapers? For the time being, it is unlikely 3D printing will surpass current construction methods for buildings 100s of feet tall as designing a 3D printer that big would produce more design problems than the construction itself. Though with the possibility of ex-situ part fabrication, we could see a quick change away from our traditional construction methods.

1. https://bit.ly/3dD9fSr 2. https://bit.ly/3dv9pvi

AI Space Factory’s Vision of “Tera” 3D Printed House.2

Elemental Factfile: Arsenic As 33

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Infamous as a spy’s best friend in a compromising situation, this element definitely has quite the gruesome reputation.

Arsenic reportedly got it’s name from the Greek word “arsenikon” meaning yellow pigment, in conjunction with a futher Greek word “arsenikos” meaning potent. Both of these are very literal descriptions of the element itself. Occuring naturally in a crystaline form, arsenic has three common allotropes, grey, yellow, and black. The brittle grey shiney arsenic is the most common form, with the yellow waxy arsenic converting into its more brittle counterpart with exposure to light at room temperature.

It is thought that the element was first isolated back in the Middle Ages, specifically 1250 by a scholar named Albertus Magnus. However is wasn’t until Paracelsus, a physician-alchamist got his hands on arsenic that it was reported to be prepared in its metallic form, taking on its title as “The King of Poisons”.

Its high toxicity is what makes this element the “King of Poisons.” However it is relatively easy to trace when used in this way, leaving behind traces in hair, urine and blood. Exposure to even the smallest amounts of arsenic can

Clead to multiple-organ failure, and

genetic damage.

Despite bad reputation, arsenic can also contribute to society in a more positive fashion through its use as a blue pigment in pyrotechnic displays or as a semi-conductor doping agent. Its toxicity can also be used for good, as it takes on the role of an insecticide, helping with wood presevation. This element is the perfect example of “don’t judge a book by its cover’” what seems like a dangerous element can actually be used for good.

Arsenic in its yellow form

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Arsenic in its grey form

Perseverance Rover – Mars 2020 Mission Perseverance Rover – Mars 2020 Mission

By Emily Goddard

At 20:55 GMT on 18th February 2021, Perseverance landed successfully on Mars after a 6 - month journey to the Red Planet.

Named by school-child Alexander Mather, Perserverance is the latest rover in NASA’s Mars program that has been exploring our solar system’s most accessible planet since the Viking missions in the 1970s. Being a terrestrial planet with a complex geology and a climate that has changed throughout history, the similarities to Earth make Mars an attractive destination to look for extra-terrestrial life.

The main scientific goals of the Mars 2020 mission continue previous missions’ work as well as introducing exciting new opportunities for discovery.

Perseverance is following in the footsteps of the Curiosity rover by examining Mars for habitability. It is looking for evidence of ancient microbial life or the environments that could have supported it by mapping the elemental distribution on the planet’s surface. A completely new venture for Mars 2020 is Perseverance’s capability to gather samples for analysis on Earth, rather than being limited by instruments that can make it to Mars. Preparations for future manned missions are also underway, investigating whether O2 can be made from the predominantly CO2 atmosphere, as well as monitoring weather changes to develop forecasting tools for potential human explorations.

The first image sent back to Earth by Perseverance after landing in the Jezero Crater. Landing site is key in search for ancient life1

Perseverance landed in Jezero Crater, a 45 km wide basin just north of the Martian equator. Inlets and outlets in the rock show that rivers supplied and drained a lake similar in size to The Isle of Wight. The water is long gone, but sediment left behind in the large fan-shaped delta is scientists’ greatest hope for finding the biosignatures this mission is searching for. Hot rocks exposed at the rim during the impact that formed the crater are a potential location of hot springs, another conceivable place to find signs of ancient organisms.

The mission is looking for what microbial life left behind, as the climate is too cold for current life to be a possibility. Stromatolites are sedimentary layers formed by microorganisms on top of the lakebed that distort layers in the rock, giving signs that life could have existed in the ancient lake, alongside organic carbon and differences in elemental distribution. Carbonate around the edge of the crater is also of interest. On Earth, carbonates are often deposited by living organisms e.g. coral reefs, but it is rare on Mars. The concentration detected on what would have been the shore of the Jezero Lake could be another site of biosignatures.

Instruments on board Perseverance2

All of NASAs missions to Mars build on knowledge and discoveries of previous missions, improving the technology and adding new ideas. Perseverance is no different, built mainly using the Curiosity rover design, but with improved entry, descent and landing technologies, analytical instruments, and technology demonstrations.

Two instruments specially designed for the mission are PIXL and SHERLOC. PIXL (named after the pixel, the smallest unit of a digital image) - Planetary Instrument for X-Ray Lithochemistry - is a micro-focus x-ray fluorescence spectrometer for examining the elemental composition of Mars’ surface. It can detect over 26 elements down to 10ppm concentrations to identify signs of biofilms formed by microbes, and has a camera to relate the elemental composition detected

The SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) measures the native fluorescence and Raman scattering of species. It will be used to detect aliphatic and aromatic organic molecules (potential biosignatures) and to detect and characterise minerals (indicators of aqueous chemistry as further proof of an ancient lake). This UV spectrometer aims to help solve the mystery of life on Mars just as Sherlock solves his mysterious cases. SHERLOC wouldn’t be complete without his trusty sidekick WATSON (Wide Angle Topographic Sensor for Operations and eNgineering), the instrument’s imaging component. Perseverance also carries two technology demonstrations: promising technologies trialled on a small scale to test concepts for later missions. Ingenuity, a helicopter the size of a chihuahua weighing only 1.8kg, is aiming to perform the first powered flight on another planet. Despite gravity on Mars being only 1/3 of that on Earth, the atmosphere is 99% thinner, so Ingenuity must be light yet powerful to produce enough lift to take off. Carbon fibre blades spinning at 2400 rpm (6x faster than passenger helicopters), have succeeded in simulated conditions on Earth, so the hope is that can be replicated out there.3

The second technology demonstration is MOXIE (Mars Oxygen In Situ Resource Utilization Experiment), an instrument designed to make oxygen on the Red Planet. This side of the Mars 2020 mission focuses solely on the possibility of human exploration. Mars’ atmosphere is 95% CO2, so O2 production in situ would be required for human survival. Less obvious perhaps, is the use of O2 to fly our explorers home again. For a four-man crew, 25 metric tons of O2 would be needed to produce enough thrust to launch the rocket from Mars. In situ production instead of shipping it from Earth would be therefore a major advantage. MOXIE pressurises the atmospheric CO2 to 1 atm, then uses a solid oxide electrolyser to split it electrochemically, producing O2 at the anode. Running at over 800°C, it needs to be coated in a gold layer to prevent the rest of the Perseverance rover from overheating. The instrument currently on Mars is the size of a car battery and produces enough O2 to keep a small dog alive. Michael Hecht, MOXIE’s Principal Investigator at MIT, estimates a fullsize system making enough O2 to launch a rocket would be slightly bigger than a household stove.3

Perseverance got us there - now we need patience

The Perseverence Rover lands on Mars (top) & Ingenuity helicopter (bottom).

The successful landing of another Mars rover and all the discoveries awaiting us are very exciting but, as with all space exploration and investigations into extra-terrestrial life, patience is required. All the samples Perseverance gathers and stores on Mars won’t be collected until at least 2028 when the combined efforts of NASA and ESA can reach them with a mission capable of returning to Earth intact. Once on Earth, analysis is a long process; lunar samples from the Apollo Missions (1969-1972) are still being studied today. As Ken Farley (NASA project scientist) explained to the BBC, there is a very high burden of proof for extra-terrestrial life. On Earth, despite controversy over the details of its origins, at least we know life exists. On Mars we don’t know if life even existed, let alone when, where or how.

So, the search for life on Mars continues, but with Perseverance’s help, maybe one day humans will reach the Red Planet, although hopefully without Matt Damon’s drama in The Martian.