Planetary Science at The University of Manchester

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We seek to understand how our Solar System's diverse environments formed and evolved through time, and how they operate today. We study samples that arrived at the Earth's surface from space (meteorites) or were brought back by space missions (such as Apollo samples from the Moon, Hayabusa samples from asteroid Itokawa). We determine the chemistry of these rock samples, and the minerals they contain, to interpret the conditions in which they formed and the physical processes that acted upon them through 4.6 billion years of Solar System history. The compositions of the planets, including the Earth, were set as they formed in a disk of dust and gas that circled the growing Sun 4.56 billion years ago. Particles called chondrules in the most ancient meteorites (chondrites) preserve a record of the chemistry of the dusty disk that we can use to understand the first stages of planet growth. By making analogues of chondrules in the lab and comparing them to meteorite samples, we can test the way that elements essential for life were mixed into the ingredients that made the Earth and other rocky planets. The first asteroids - planetesimals - were formed from chondrules, as well as a mixture of tiny mineral grains. Fast-decaying radioactivity heated these planetesimals soon after they formed, causing them to melt inside. We will conduct experiments to study how the compositions of melts change during the first stages of heating, when only a small part of the planetesimal melts. We will also analyse the minerals as well as the chemical composition and isotopes in meteorites from these melted planetesimals. This will enable us to track the history of heating and cooling, and so learn more about when melting took place. It will also show us how small asteroids evolved and how elements behaved during the formation of the planets. We will then better understand the starting compositions of planets within our own Solar System and around other stars. The solar system is continuously irradiated by high-energy particles that originate elsewhere in our galaxy. By studying the effects of these particles on meteorite samples, we will investigate how our solar system's galactic environment has changed over its lifetime.The Moon has had a long and varied geological history. Lavas flowed from volcanoes on the Moon's surface after rocks in the interior of the Moon melted. We will study some of the more unusual types of rocks from the Moon that tell us about how the molten material changed in composition as it rose towards the surface. Through careful studies of the minerals that make up lunar rocks, and by measuring their ages, we will be able to piece together the Moon's volcanic past, and understand the role of internal or externally driven partial melting. The only samples from Mars that we can study in the laboratory are martian meteorites. Martian meteorites include some that represent lavas which originated deep inside Mars, and others that are pieces of the broken-up surface of the planet. We will measure the chemistry of the halogen elements and noble gases in the interior of Mars through analysing martian meteorite samples. This will help us understand how volatile elements (elements that are easily turned into gas) and water were added to the rocky planets, which is important for understanding their sources and the timing of when they were added to the Earth.