Thank you to all of you who attended this Monday! I hope that all of you enjoyed it. First the question was posed: Do you think there is life outside Earth, somewhere in the universe? All the answers were yes! - there is life in the universe. The second question was: Do you think that we will find life in the universe? The answer to this question was a little shaky to say the least; no one was prepared to commit to us finding life in the universe. So what is needed for life? Here is what you said:
The Drake equation is a way of showing how likely it is that there is life in the universe which is actively trying to communicate with us. N - the number of communicating civilizations in our galaxy R* - The rate of star formation in our galaxy fp - the fraction of these stars which have planets ne- the number of these planets which have the potential to support life; which are earth like fl - the fraction of these earth-like planets which actually develop life fi - the fraction of this life which develops intelligence fc - the fraction of this intelligent life which develops communicative technology L - lifetime of such a civilization The first two terms of the equation are perhaps the ones most based on factual knowledge. We know that the rate of star formation in the galaxy is around 7 stars per year. There has been a lot of research about exoplanets recently, are we believe that almost all stars will have a planetary system of some sort. After that is when the things start moving into the realm of guesswork. We can move to each term guessing a number for each one, simply because we don't know enough about the universe. We only have one example of a solar system that we can scrutinize, and only one form of life: perhaps the greatest example of inaccurate extrapolation. There are however some terms which can create intrigue in a discussion: the fraction of life which develops intelligence. Would it be wrong to say that this is 100%? If life develops, surely it would evolve to intelligent beings? The terms after that is an interesting one too. We are currently searching for extraterrestrial life by sending radio waves into space. Our form of communicative technology is electromagnetic radiation. Based upon our knowledge of the universe, EM waves are a widespread phenomena; definitely not something we have created. Would it be a stretch to say that intelligent living being somewhere in the far reaches of the galaxy also uses radio waves? Probably not. But then again, who's to say that these aliens haven't developed something like telepathy? As for the lifetime of such as civilizations, how long will they actively broadcast for? A better question would be how longs are we going to broadcast for? 100 years? 1,000? 10,000? In short, we simply do not have enough knowledge to make a prediction which is anywhere near accurate. However, it is a great way to speculate about life in the universe. Put in you own number and see what result you get! (We got about 2500 communicating civilizations in our galaxy on Monday) Shubhangi
0 Comments
Thank you very much to everyone who attended our student presentation on the world of Genetic Engineering and its future, co-presented by myself Evelyn Day and Jenny Marsh. Initially we covered a brief background into what genes are, where they are and what exactly they do in the body, and why in some cases this can be a problem, such as mutated genes that can cause disease and disability in people. We then explored many areas of the wide field of genetic engineering from some of the basic techniques of genome editing that are commonly used today; gene insertion into an organism via a virus or agrobacterium vector, all the way to DNA ‘cutting and pasting’ with specific DNA enzymes called DNA endonucleases and ligases. We also explored their roles in the research of genetics, for example with Knockout Mice as a valuable research resource into the more specific functions of different genes, and other more medicinal applications in different forms of corrective Gene Therapy, drawing on more specific examples such as a potential genetic treatment for Cystic Fibrosis.
We then moved on to one of the more topical aspects of Genetic engineering today, CRISPR-Cas9, an only relatively recently discovered ancient immune mechanism present in almost all bacteria that allows them to fight and acquire immunity to viral infections. We spoke a little about CRISPR’s history and its recent discovery in 2012 by Jennifer Doudna and Emmanuelle Charpentier, and then on to what it means for genetic engineering. After a viral infection of a bacterium, the CRISPR immune response is designed to target a specific section of that infecting viral DNA that has been incorporated into the bacterial DNA, very quickly and very accurately. The Cas9 ‘cleaver’ protein in the Cas9-RNA complex ‘cuts out’ the offending viral DNA section, leaving a gap in the bacterial DNA (which the organism then closes with one of two response pathways). This gap is crucial for scientists as they are now able to stuff new DNA into it. The revolutionary aspect about CRISPR is the precision, accuracy and reliability to which it functions, traits which most other genome editing techniques fail to exhibit. Its targeting system is very easily reprogrammed to whatever we want, its speed and efficiency cuts the process time from weeks to days, and its simplicity makes it an available tool almost anywhere in the world. We went on to speak about the mixed implications that this has, such as creating artificial gene drives with this technology, and the topic that seems to be often buzzing around the media; ‘designer babies’, and the fact that CRISPR has such a high accessibility to a wide range of scientists of many different abilities and means, pretty much anywhere in the world. Finally, whilst still meditating on these thoughts we ended the presentation with questions on how these powerful tools will shape us, the human race, throughout the future, and what rules and regulations should we put in place to stop ourselves going too far? I hope you all enjoyed our talk! Written by Evelyn Day Mr. Robin Stafford Allen gave a fantastic talk on Nuclear Fusion and Energy. He told us why nuclear fusion could be very important in the future. The Earth's growing population as well as increasing wealth in developing counties means that the demand for energy is increasing. Mr. Allen showed us how renewable energy sources may not the answer as they are unreliable and relatively inefficient compared to burning fossil fuels, but also how fossil fuels are unsustainable for the future and contributing to global warming. So fusion might just be the answer. ITER - The World's Largest Fusion Experiment Mr. Allen went on to tell us the basics of what fusion is and how it can produce energy. In fusion, they use two heavy isotopes of hydrogen, Deuterium and Tritium to create Helium and a high energy neutron. In the process 0.4 of the mass of the nuclei is lost and released as energy. There is a lithium blanket that captures these energetic neutrons and fusion of the lithium and the proton occurs producing Helium, Tritium (which can be used in the main fusion reaction) and heat, this heat can be used to boil water, produce steam, drive a generator and produce energy. Reacting 1 gram of Deuterium and Tritium produces the same amount of energy as burning 10 million grams of coal or gas. Mr. Allen explained that if fusion is to occur the isotopes have to be heated and turn into a plasma, they are heated in three ways, Ohmic heating, Radio Frequency heating and Neutral beam heating. He said however if the plasma touches the walls of the reactor it would severely damage the machine, so to stop the plasma from doing this, a magnetic field is created to hold the charged particles away from the wall. Mr. Allen explained that to create this strong magnetic field they must use electromagnets, and for the field to be so strong a huge current has to run through the machine. But because of resistance, everything heats us very quickly so the machine can only be switched on for 15 seconds before it overheats and has to be turned back off and left to cool. This problem is in a reactor called JET in Oxford. Mr. Allen told us about a new reactor being built in France called ITER which uses superconductors so the machine can keep on running without heating up. However ITER has limited funding from governments and the high energy protons damage the materials that the machine is built from, but because high energy protons are only really produced in these fusion reactions there isn't a lot of research on resistant materials. Mr. Allen finished with telling us the many advantages to fusions, there are little or no environmental impacts, it doesn't produce only ‘long-lived’ radioactive waste and the resources needed are abundant in the Earths crust and water.
Written by Nina Mulder-Qureshi Professor Paul Harrison came in to talk to us about particle physics. He began by telling us about the standard model of elementary particles and about quarks and gluons- including the composition of protons and neutrons, and how all quarks are point like (can't be measured) and bound. He then moved on to tell us about the 'Guiding Principles of Particle Physics':
He then moved on to talk about his work at CERN, as well as telling us briefly about the discovery of the Higgs boson particle, and what is made on particle colliders. Lastly, he talked about the questions still facing particle physicists today: Is the Higgs boson as expected? Why is the Higgs bosons mass stable? Is the dark matter of the universe really a new undiscovered particle? How to unify strong force with weak and electromagnetic? Why do elememtary particles take the masses they do? Written by Jess Astley |
AuthorOur blogs are written by the girls that attend this society. Archives
June 2020
Categories |