British space physicist Monica Grady is best known for her work on meteorites. She was born in Leeds, West Yorkshire, the United Kingdom, on July 15, 1958. As a Professor of Planetary and Space Science, Grady is presently employed by the Milton Keyes Open University in the United Kingdom. She also is the director of the Physical Sciences Department. Grady enrolled in Durham University in 1976 to study geology and chemistry, and he received his degree in 1979. Later, after conducting research on carbon in meteorites at Darwin College in Cambridge, she enrolled in a Ph.D. program, which she eventually finished in 1983. From that time, she has attained a global recognition in meteoritics for her various publications regarding nitrogen and carbon isotope geochemistry of ancient meteorites, interstellar components of meteorites as well as Martian meteorites.
In 2000, she was appointed a Fellow of the Meteoritical Society. In 2003, she delivered Lectures on; "A Voyage in Space and Time" at the Royal Institution Christmas. Subsequently, Monicagrady, Asteroid (4731) got named in her honor. Also, as a Higher Scientific Officer, she worked as a curator in London at the Natural History Museum handling meteorites. She later on became the Head of the Meteorites and Cosmic Mineralogy Division. Monica also served in the Earth Sciences Department at London University College as an Honorary Professor from 2004 to 2007. In 2005, she joined the Open University for a position holds up to date. In 2012, Grady became "the Commander of the Order of the British Empire" (CBE), an honor she got for her great contribution to space sciences. In the same year she became a Fellow of the Institute of Physics, then a Fellow of the Geochemical Society later in 2015. Besides, Monica has been a Fellow of the Mineralogical Society of Ireland and Great Britain since 1992, and a member of the Royal Astronomical Society since 1990. From 2012 to 2013, she became the first British president of the International Meteoritical Society.
In 2014, Monica spoke spoke with BBC News regarding the significance of Rosetta-the spacecraft. In 2016, she received the Coke Medal of the Geological Society of London award for her work on science communication. Monica is a member of Euros-Cares, an EU-funded Horizon 2020 project that aims at developing a plan for a European Sample Curation Facility. A project intended to curate valuable samples brought from Solar System explorations of comets, the moon, Mars, and asteroids. Grady has worked with other several astronomers to put together the connections between the dusts around stars and those analyzed in the laboratory. At the moment, she is working with some Norwegian scientists to create a miniature combined infrared microscope and spectrometer, to be deployed on the surface of an asteroid or Mars. Besides, she has led other major research programs in the study of meteorites (Grady, 3). For instance, one of her major work has been to comprehend and understand water and carbon history on Mars as well as the interactions between hydro (cryo)sphere, atmosphere, and surface. This has been done through the examination of the materials formed by altering processes on the surface of Mars as well as studying the minor components of Martian meteorites.
"Visitors from Outer Space"
In her 1999 article "Visitors from outer space", Grady gives an overview of meteorites and how they affect the surface they are found on. In particular, she states that about four particles of extraterrestrial materials land on earth in an hour per square kilometer. Meteors can come from the asteroid belt and also from the Moon. Regarding the latter, Lunar meteorites are often compared with other samples brought to Earth by the Luna and Apollo Missions that took place between 1969 and 1976. In particular, the Moon's surface is covered by craters that form as a result of impacting of bodies. If the impactor travels at an essential speed and on favorable trajectory, the force of the impact can eject material from the surface at a speed fast enough to overcome the gravity on the moon and launch into space (Grady, et al, 5). Subsequently, the launched material may go into an interplanetary space orbit, while some of the material may land on earth as a meteorite. In a similar manner, rocks are launched from Mars onto the Earth. According to this report, about twelve meteorites have been ejected from Mars because of the impact of materials on the surface of Mars. The meteorites ejected from Mars to earth are known as Martian Meteorites.
Martians meteorites can be distinguished from other types of meteorites by age. Regarding this, most Martian meteorites do not appear as old as the other types of meteorites. While other meteorites date back to about four-thousand-six-hundred million years, the Martian meteorites appear much younger, dating to about one-hundred and eighty million years. This means that Martian meteorites crystallize from other molten planetary-sized bodies, long after asteroids have been formed and therefore cannot emerge from the asteroid belt. NASA has helped to unravel the origin of Martian meteorites by comparing them to the components of Mars. From the data collected during the 1979 NASA expedition of Antarctica, the researchers discovered an eight-kilogram meteorite around the Victoria Land region. The meteorite (named EETA79001) contained many dark patches made of glass seen all around the meteorite's pockets. The glass patches formed as a result of localized melting when the rock was launched from its parent's surface by a heavy impact (Grady, 6). During the analysis of the glass components in a laboratory, trapped gases were released. These gases had same composition as the atmosphere on Mars. Another Martian meteorites discovered in 1996 in Antarctica (named ALH 84001) weighed almost two kilograms and contained patches of carbonate. In particular, the carbonates appeared orange and lined with dark and light layers showing a change in composition of the stone's mineral grains as a result of changes in acidity, temperature and fluid composition (Grady, et al, 3). The oxygen and carbon found in the carbonates show that the mineral grains of the meteorite were produced in low temperatures from the atmosphere on Mars. These and many others numerous researches show that life may have existed on other planets such as Mars even though this is yet to be proven.
Grady defines Meteorites as a various sets of extraterrestrial materials that represent the solar system and planetary materials in several forms. Therefore, studying meteorites enables humans to understand the evolution of the Solar System. Besides, studying meteorites aids in the study of the starts and any other physical things that have contributed towards the formation for the solar system. Studying Martian meteorites in particular allows humans to understand the beginnings of life on other planets. Besides being associated with the seeds of life, meteorites also influence evolutionary pathways as a result of the catastrophic impact and environmental changes.
Meteorite Origins
In between Jupiter and Mars at the gap between gas and rock in the Solar system lied the asteroid belt-a place where most meteorites come from. There are numerous asteroids the largest (Ceres) measuring about nine-hundred and fourteen kilometers. Asteroids in particular are metallic, rocky or carbonaceous bodies formed from materials that remain after other planets formed. Jupiter has a super strong gravitational pull that stopped these bodies from forming a single planet. Occasionally, Jupiter alters the orbit of an asteroid making the asteroid to collide with another one, thus causing break up. On a closer analysis, the asteroids contain cratered surfaces formed as result of constant collisions within the asteroid belt (Grady, 4). Subsequently, fragments of the disrupted asteroids fall on the Earth as meteorites. These meteorites have composition just like their parent asteroids. For this reason, meteorites can be divided into several groups with each group representing diverse staged in the formation of planets. The main types of meteorite include iron,stone and stony-iron. Most meteorites fall into the stony category (about ninety-six percent). They are made of up similar minerals such as plagioclase, pyroxene and olivine as many terrestrial rocks that contain minerals such as oxygen, iron, silicon, calcium, magnesium and aluminium (Grady, et al, 5). The stony meteorites have been further divided into chondrites (unmelted meteorites that retain their chemical components that resemble those of the parent material) and achondrites. Achondrites refer to ingenious rocks such as basalts that form after melting from the parent bodies. In particular, the chemical composition of achondrites appears different from those of the parent bodies because they do not contain chondrules.
Iron meteorites form when parent bodies go through extensive melting process. The iron meteorite parent bodies are sufficiently larger and therefore retain heat during formation. Iron-nickel metal that forms during the reduction of silicate materials often migrate as a result of gravity to the center of the parent asteroids forming a core while the less thick silicates rise to the surface to form a crust. Stony-irons on the other hand are meteorites that contain both metal and stone. Pallasites are the most common type of stony-iron meteorites formed as a result of melting from the parent bodies. Even though the stony and iron meteorites provide a lot of information regarding planetary differentiation, the chondrite category of the stony meteorites provide the most important information regarding the origin and evolution of the Solar System (Grady, 6). This is because chondrites (carbonaceous chondrites in particular) contain chemical compositions that appear similar to those of the sun. In addition to containing chondrules, chondrites also contain other organic compounds such as hydrocarbons, carboxylic and amino acids that created volatile materials. These volatile materials in turn helped to form the earth's oceans and atmosphere.
In conclusion, Grady has proven herself as an outstanding meteorological researcher. Her publications show an in-depth passion and intellectual capability to handle meteorological studies and thus she has greatly contributed to the academic world. While scientists and enthusiasts continue to study meteorites, Grady has provided a base for future further studies into understanding the planetary and the Solar System at large.
Works Cited
Reliable Sources
Grady, M. M. The history of research on meteorites from Mars. In The history of meteorites and key meteorite collections: fireballs, falls and finds. Geological Society, Special Publication 256, 2006
Grady, M. M., Verchovsky, A. B. & Wright, I. P. Magmatic carbon in Martian meteorites: attempts to constrain the carbon cycle on Mars. International Journal. Astrobiol.3, 117-124, 2004.
Grady, M.M & Wright, I. The Carbon Cycle on Early Earth and on Mars. Philosophical Transactions of The Royal Society, 2006.
Unfamiliar Sources
"Professor Monica Grady."Durham University, 2013, https://www.dur.ac.uk/ias/fellows/0910fellows/grady/.
"RAS Awards 2007."Wiley Online Librabry, 2008, http://onlinelibrary.wiley.com/doi/10.1111/j.1468-4004.2008.49135_11.x/pdf.
Bias Sources
"Monica Grady."En.Wikipedia.Org, 2017, https://en.wikipedia.org/wiki/Monica_Grady.
