In this research programme, planetary scientists and engineers from the University of Glasgow and the Scottish Universities Environmental Research Centre have joined forces to answer important questions concerning the origin and evolution of asteroids, the Moon and Mars. The emphasis of our work is on understanding the thermal histories of these planetary bodies over a range of time and distance scales, and how water and carbon-rich molecules have been transported within and between them. One part of the consortium will explore the formation and subsequent history of asteroids. Our focus is on primitive asteroids, which have changed little since they formed 4500 million years ago within a cloud of dust and gas called the solar nebula. These bodies are far smaller than the planets, but are scientifically very important because they contain water and carbon-rich molecules, both of which are essential to life. We want to understand the full range of materials that went to form these asteroids, and where in the solar nebular they came from. Although they are very primitive, most of these asteroids have been changed by chemical reactions that were driven by liquid water, itself generated by the melting of ice. We will ask whether the heat needed to melt this ice was produced by the decay of radioactive elements, or by collisions with other asteroids. The answer to this question has important implications for understanding how asteroids of all types evolved, and what we may find when samples of primitive asteroids are collected and returned to Earth. Pieces of primitive asteroids also fall to Earth as meteorites, and bring with them some of their primordial water, along with molecules that are rich in carbon. Many scientists think that much of the water on Earth today was obtained from outer space, and consortium researchers would like to test this idea. In order to understand the nature and volume of water and carbon that would have been delivered by meteorites, we first need to develop reliable ways to distinguish extraterrestrial carbon and water from the carbon and water that has been added to the meteorite after it fell to Earth. We plan to do this by identifying 'fingerprints' of terrestrial water and carbon so that they can be subtracted from the extraterrestrial components. One of the main ways in which this carbon was delivered to Earth during its earliest times was by large meteorites colliding with the surface of our planet at high velocities. Thus we also wish to understand the extent to which the extraterrestrial carbon was preserved or transformed during these energetic impact events. The formation and early thermal history of the moon is another area of interest for the consortium. In particular, we will ask when its rocky crust was formed, and use its impact history to determine meteorite flux throughout the inner solar system. To answer these questions we will analyse meteorites and samples collected by the Apollo and Luna missions to determine the amounts of chemical elements including argon and lead that these rocks contain. Information on the temperature of surface and sub-surface regions of Mars can help us to understand processes including the interaction of the planet's crust with liquid water. In order to be able to explore these processes using information on the thermal properties of martian rocks that will soon to be obtained by the NASA InSight lander, we will undertake a laboratory study of the effects of heating and cooling on a simulated martian surface. Hot water reaching the surface of Mars from its interior may once have created environments that were suitable for life to develop, and minerals formed by this water could have preserved the traces of any microorganisms that were present. We will assess the possibility that such springs could have preserved traces of past martian life by examining a unique high-altitude hot spring system on Earth.

Over the last 25,000 years, East African climate has responded to changes in the Earth's orbit (mainly precession) that influence long-term variations in monsoonal rainfall and the migration of the intertropical convergence zone. But climate of earlier periods, back to 250,000 years, is less well understood as few continuous high resolution terrestrial records exist. This is a major gap in our understanding of equatorial climate from a region critical to the evolution of our own species. The African megadrought hypothesis states that droughts lasting many thousands of years occurred during the last interglacial (130,000 - 80,000 years ago) across tropical Africa. Evidence from the few sites investigated indicate they were of a severity greater than any droughts of succeeding time periods, and had major implications for evolutionary processes, for example continent wide migrations in Homo sapiens. Such long and intensely dry events in the history of African climate are an unexpected phenomenon, and their precise timing, origin and extent, has yet to be established. We hypothesise that megadroughts arose due to monsoon failure caused by changes in the shape of earth's orbit around the sun (the ~100,000 year eccentricity cycle), amplifying changes in the seasonal distribution of solar radiation (the ~21,000 year precession cycle). In order to fully understand these extreme climatic events, we will explore climate changes in the East African equatorial region spanning two glacial-interglacial cycles (i.e. the last ~250,000 years) giving critical context to the megadroughts and their causes. The project focuses on the sedimentary record from Lake Challa, a deep lake on the flank of Kilimanjaro. Unlike other studies from East Africa, the easterly position of Lake Challa places it beyond the direct influence of the Atlantic climate system, thus removing this aspect as a possible forcing and allowing us to isolate a record of monsoonal variation. The outstanding potential of these lake sediments to provide a long, sensitive repository of environmental change data has been established by a prior study of the last 25,000 years, that resulted in multi-disciplinary articles in 'Nature' on orbital forcing of climate, 'Science' on the laminated sediments and relation to ENSO, and 'Geology' concerning the seasonality of climate variations and the Kilimanjaro ice core. Additional data sets (published in other journals) confirm that the environmental proxies and dating methods proposed here will deliver a high quality record from this lake. The age of the deeper sediments has been estimated from seismic profiles of the sedimentary layers in the lake; new, absolute dates are required to identify the basal sediment age and rates of subsequent sedimentation. This project will lead in modelling of sediment ages from the new, deep cores through radiocarbon dates, palaeomagnetism to detect the presence of well-dated magnetic reversals and dating of volcanic ash layers through Ar/Ar dating and chemical correlation. Carbon and oxygen isotope data from diatom silica are excellent tools to reveal the megadroughts due to their sensitivity to humid/arid shifts as already demonstrated during the last 25,000 years. This project is part of an international consortium, partly funded by the International Continental scientific Drilling Program to recover cores from the lake. Our international partners have already gained support from their own national funding councils and will contribute complimentary environmental proxies (e.g. pollen, organic biomarkers) as well as additional dating (Ar/Ar) and, finally, climate modelling (ranging from local hydrology to global climate modelling) used to understand the global significance of our results in terms of forcing factors. We have Kenyan and Tanzanian collaborators, who will also act as conduits to ensure our discoveries help inform ongoing and future conservation needs and development strategies.

In this consortium scientists from three UK institutions have come together to explore the development of rocky bodies within our solar system, and particularly in relation to the presence and properties of the key ingredients for life, namely water and carbon-rich molecules. One focus of our work will be on asteroids, samples of which have come to Earth as meteorites. These objects formed very early in the history of the solar system and evolved quickly, probably driven by internal heat from the decay of radioactive chemical elements. We want to know where in the solar system some of these asteroids formed, how long it took them to grow and how quickly they cooled down. We would also like to understand how heating and cooling affected water and carbon-rich molecules that became incorporated into the asteroids as they grew. These questions will be answered by using isotope analysis to determining the ages of different types of minerals, and by studying changes to the structure of carbon-rich compounds with laser beam techniques. Results from this work will provide new understandings of the evolution of asteroids that can be used to help interpret samples of them that will soon be returned to Earth by robotic missions. We will also study meteorites from Mars. This planet is an intermediate stage in evolution between the asteroids, which 'died' as they lost their heat and liquid water thousands of millions of years ago, and the Earth that remains an active planet with internal heat, liquid water and complex carbon-rich molecules including life. The Martian meteorites that we will analyse formed about 1300 million years ago when the planet was still hot enough that parts of its outer surface could melt, and they preserve traces of liquid water that flowed through the rocks. By studying the minerals in these rocks and the chemical elements from which they are made, we will explore how crystals grew as the molten rock cooled, and will also determine when the water was present. Today the surface of Mars is very hostile to life, with extremes of temperature, little or no liquid water and intense irradiation by ultraviolet light. However, brief occurrences of water on the surface of Mars today, and past hot-spring sinter deposits, may contain evidence of life, yet their propensity to do so is poorly understood. As sending robotic geologists to Mars is very costly, we will discover whether these environments can harbor molecular signs of life by studying martian analogue sites in the mountains of Chile. Soils in these areas are very dry, their temperatures fluctuate over a wide range and they are bathed in ultraviolet light. We will try to find traces of past life in these soils, and we will explore molecular preservation further by simulating martian conditions in the laboratory. This new information will tell us where on Mars we should focus the search for traces of life during future robotic and manned missions. The results of this research will be made freely available to other scientists worldwide so that improved models of planetary evolution can be developed. These new data and models will then help to guide the future exploration of asteroids and Mars, including the exciting missions in the next few tens of years that will return samples to Earth. Our research will also be of interest to scientists who study the history of the Earth, its climate and its life, and to industry through the new analytical procedures and technologies that we will develop. As our work will explore new and exciting science topics, it will be of great interest to the public and will be communicated via science festivals, newspapers and social media.

In this research programme, planetary scientists and engineers from the University of Glasgow and the Scottish Universities Environmental Research Centre have joined forces to answer important questions concerning the origin and evolution of asteroids, the Moon and Mars. The emphasis of our work is on understanding the thermal histories of these planetary bodies over a range of time and distance scales, and how water and carbon-rich molecules have been transported within and between them. One part of the consortium will explore the formation and subsequent history of asteroids. Our focus is on primitive asteroids, which have changed little since they formed 4500 million years ago within a cloud of dust and gas called the solar nebula. These bodies are far smaller than the planets, but are scientifically very important because they contain water and carbon-rich molecules, both of which are essential to life. We want to understand the full range of materials that went to form these asteroids, and where in the solar nebular they came from. Although they are very primitive, most of these asteroids have been changed by chemical reactions that were driven by liquid water, itself generated by the melting of ice. We will ask whether the heat needed to melt this ice was produced by the decay of radioactive elements, or by collisions with other asteroids. The answer to this question has important implications for understanding how asteroids of all types evolved, and what we may find when samples of primitive asteroids are collected and returned to Earth. Pieces of primitive asteroids also fall to Earth as meteorites, and bring with them some of their primordial water, along with molecules that are rich in carbon. Many scientists think that much of the water on Earth today was obtained from outer space, and consortium researchers would like to test this idea. In order to understand the nature and volume of water and carbon that would have been delivered by meteorites, we first need to develop reliable ways to distinguish extraterrestrial carbon and water from the carbon and water that has been added to the meteorite after it fell to Earth. We plan to do this by identifying 'fingerprints' of terrestrial water and carbon so that they can be subtracted from the extraterrestrial components. One of the main ways in which this carbon was delivered to Earth during its earliest times was by large meteorites colliding with the surface of our planet at high velocities. Thus we also wish to understand the extent to which the extraterrestrial carbon was preserved or transformed during these energetic impact events. The formation and early thermal history of the moon is another area of interest for the consortium. In particular, we will ask when its rocky crust was formed, and use its impact history to determine meteorite flux throughout the inner solar system. To answer these questions we will analyse meteorites and samples collected by the Apollo and Luna missions to determine the amounts of chemical elements including argon and lead that these rocks contain. Information on the temperature of surface and sub-surface regions of Mars can help us to understand processes including the interaction of the planet's crust with liquid water. In order to be able to explore these processes using information on the thermal properties of martian rocks that will soon to be obtained by the NASA InSight lander, we will undertake a laboratory study of the effects of heating and cooling on a simulated martian surface. Hot water reaching the surface of Mars from its interior may once have created environments that were suitable for life to develop, and minerals formed by this water could have preserved the traces of any microorganisms that were present. We will assess the possibility that such springs could have preserved traces of past martian life by examining a unique high-altitude hot spring system on Earth.