* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Presentation - The Stimulating Physics Network
Observational astronomy wikipedia , lookup
Aquarius (constellation) wikipedia , lookup
Outer space wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Geocentric model wikipedia , lookup
Astronomical unit wikipedia , lookup
IAU definition of planet wikipedia , lookup
Planets beyond Neptune wikipedia , lookup
Definition of planet wikipedia , lookup
Dialogue Concerning the Two Chief World Systems wikipedia , lookup
Late Heavy Bombardment wikipedia , lookup
Circumstellar habitable zone wikipedia , lookup
Exoplanetology wikipedia , lookup
Extraterrestrial atmosphere wikipedia , lookup
Astrobiology wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Comparative planetary science wikipedia , lookup
Timeline of astronomy wikipedia , lookup
EXOPLANET PROPOSAL Lancaster Girls’ Grammar School CONTENTS INTRODUCTION All measurements are relative to Earth (e.g. mass, radius, etc.) INTRODUCTION Today we face a huge problem. The Earth has not only run out of minerals, fuel and elements to mine for fuel, the Sun is nearing the time in its life where it is expanding and turning into a Red Giant. This means that temperatures are soaring; the Arctic has already been lost. In a million years, the Earth will be inhabitable- but we face a more looming problem. INTRODUCTION We have received a message in binary code that has been translated. It says: "People of Earth, your attention please. This is Prostetnic Vogon Jeltz of the Galactic Hyperspace Planning Council. As you will no doubt be aware, the plans for development of the outlying regions of the Galaxy require the building of a hyperspatial express route through your star system, and regrettably your planet is one of those scheduled for demolition. There's no point in acting all surprised about it. All the planning charts and demolition orders have been on display in your local planning department on Alpha Centauri for fifty of your Earth years, so you've had plenty of time to lodge any formal complaint and it's far too late to start making a fuss about it now.“* *As predicted by Douglas Adams in ‘The Hitchhiker's Guide To The Galaxy’ INTRODUCTION This is from our neighbouring galaxy Andromeda, and they are scheduled to arrive in about 350 years. Emergency space-programmes have been set up, and countries have made alliances- including rival superpowers the United States of America and Russia. The message is clear: if the human race is to survive, then we must find another planet- and fast. Scientists have been working around the clock to locate another planet, and several candidates have emerged: BML-0798a, BML-0798b, BML-0798c and BML-0798d. EXOPLANETS WHAT IS AN EXOPLANET? An exoplanet is also known as an extra solar planet and is a planet outside of our solar system. That is, it does not orbit our sun (the exo prefix means outside in Greek). Until now, scientists have found mainly gas planets, which are easier to find than small or rocky planets, as gas planets are usually massive, like our resident gas giants Jupiter and Saturn. This is exoplanet Kepler 22b. WHAT IS AN EXOPLANET? Scientists think there are many billions of planets in the Milky Way galaxy, not only occurring in solar systems, but it is believed that many are free-floating planets, which means that they were either never gravitationally bound to a star, brown dwarf (small body with low mass, star too cold to start nuclear reactions) or any other such object, or it was ejected from its system. The nearest know exoplanet to us is Alpha Centauri Bb. We could try to communicate with potential inhabitants of these planets, but we would have to send signals in wavelengths like infrared, radio or visible. The wavelengths would have to be different than natural signals. If we tried to communicate any other way, it may not work as we may not know if the inhabitants would be sufficiently developed form a technical or intellectual point of view. This is exoplanet Alpha Centurai Bb. THE TRANSIT METHOD THE TRANSIT METHOD To detect exoplanets, scientists analyse light curve graphs. When a planet passes between our line of sight and a star, the brightness of the light dips. This is not the luminosity of the star dimming, it is the planet blocking light from it. This is called a transit. However, this can only be used with exoplanets that cross our line of sight and have a star behind them. Also, they need very strong light detectors and telescopes to locate them. We have replicated this, and the video is on the next slide. REAL TRANSIT GRAPHS The graph we got from our experiment looked like this: REAL TRANSIT GRAPHS However, graphs scientist analyse can look like this: THE HABITABLE ZONE WHAT IS THE HABITABLE ZONE? The habitable zone-or the goldilocks zone- is the area around a star where there could be liquid water. The light from a star gives off just the right amount of heat, like in goldilocks and the three bears. The distance between stars and their planets are measured in Astronomical Units or AU. For example the distance between the earth and the sun is 1AU. THE HABITABLE ZONE EQUATIONS The goldilocks zone depends on the size and brightness of the star. If the star is very large and bright the goldilocks zone will be further away from the star, and the goldilocks zone will be closer to the star if the star is smaller and less bright. The Earth is the only planet in our solar system that is in the goldilocks zone. We can calculate the habitable zone by doing the following equations, with l being the luminosity of the star compared to that of the Sun: Inner edge= √L×0.7 Outer edge= √L×1.5 THE HABITABLE ZONE OF THE EXOPLANETS We calculated the habitable zone for the solar system BML-0798 by doing the following: Inner edge= √L×0.7 =√0.024×0.7 =0.1084435337… =0.108 AU Outer edge= √L×1.5 = √0.024×1.5 =0.2323790008… =0.232 AU EXOPLANET RATINGS Planets that are in the habitable zone in the solar system BML-0798 have to be between 0.108 AU and 0.232 AU away from the star. Therefore: BML-0798a- 10/10 as it’s in the habitable zone. BML-0798b- 10/10 as it’s in the habitable zone. BML-0798c- 0/10 as it’s not in the habitable zone. BML-0798d- 0/10 as it’s not in the habitable zone. DIAGRAM TO SHOW THIS Here is a graph to show the habitable zone of the exoplanets: GRAVITY WHAT IS GRAVITY? Gravity is found everywhere in the universe between all objects. The exact definition of gravity is in dispute. Some scientists believe it is made up of particles called gravitons which travel at the speed of light; other scientists believe otherwise. However we do know what it does and why it is needed. Gravity is scientifically referred to as "acceleration due to gravity" or "gravitational field strength". Sir Isaac Newton famously discovered that gravity is the force of attraction that exists between objects and that a force is required to change the speed or direction in which an object is moving. A Newton meter doesn't measure the gravitational pull required for an object to be moved, nor was it invented by Isaac Newton! It was in fact named in his honour. WHAT IS GRAVITY? Gravity from a specific object has an infinite distance in all directions. However, the strength of the gravity becomes significantly less as the distance decreases. The moon’s gravity affects the ocean tides on Earth but cannot be noticeably felt. At the centre of the core of the earth the gravitational pull is 0 as the Earth’s entire mass is exerting gravitational pull equally in all directions. The gravitational pull in the Dead Sea is therefore lower than that of Mount Everest. However, just below the surface gravity increases until you reach the section between the outer core and lower mantle as the Earth's core is substantially denser than the outer layers. To see a demonstration of how gravity works, see ‘Isaac Newton’s Discoveries’. WHAT IS GRAVITY? Mass is measured in kg or lb and weight is measured in Newtons. If you went to the moon, your weight would be approximately a 1/6 of what it currently (which is why you can float on the moon) is but your mass would stay the same as Newtons is the force you exert in relation to the gravity. As the gravitational field strength on the moon is less your weight is too, but mass stays the same because mass is a measure of matter, and that doesn’t change. HOW GRAVITY IS CALCULATED Gravitational field strength varies from place to place across the Earth, in addition to planet to planet. This is because the amount of gravity is calculated by: Gravity = Mass/radius squared The gravity varies due to the Earth not being a perfect sphere- it is an ellipsis shape; a squashed sphere that bulges in the middle. Nearer the equator gravity is less as the distance between the surface and the centre of the earth is greater. An experiment done by scientist proves that gravity varies across the globe. KERN THE GNOME Kern is a very important piece of scientific equipment in the shape of a garden gnome – an object whose mass cannot change. This is because it cannot gain mass from consumption of food or lose it from exercise. Nor can air get into the gnome and interfere with the results as there are no pores. Kern has travelled across the world and been weighed to see how gravity varies from place to place. KERN THE GNOME In the experiment a set of precision scales pre-calibrated to local gravity at Kern HQ, Balingen, Germany was used. They’re accurate enough to show the relatively minute differences recorded, accurately. Kern weighed most in the South Pole's Amundsen-Scott Research Station (309.82g) and second most in London (308.66g). His weight dropped over 2g to 307.56g in Mumbai, which is a lot closer to the equator so closer to the Earth's core. An underground laboratory recorded a low result as well. Scientists say you can weigh 0.5% more or less whilst travelling around the world. DOES GRAVITY VARY ON OTHER PLANETS? An experiment like the Kern the Gnome one would be rather costly to undertake on another planet so it has not been done, however scientists do believe, following other evidence and scientific formulae, that gravity varies approximately in the same way that it does on Earth. EXOPLANET GRAVITIES We calculated the gravity of the four proposed exoplanets. They were: BML-0798a M=4, r=2 so m/r squared is 4/4 =1 PERFECT BML-0798b M=27, r=25 so m/r squared is 27/125 = 0.43 (POSSIBLE) LOW GRAVITY EXOPLANET GRAVITIES BML-0798c M=25, r=49 so m/r squared is 25/2401= 0.01 VERY LOW GRAVITY BML-0798d Mass=4 Radius=16 so m/r squared is 4/256= 0.02 VERY LOW GRAVITY RATINGS OF EXOPLANETS BML-0798a- 10/10 as the gravity is identical to Earth’s. BML-0798b- 7/10 as the gravity is too low for us to live for a long time, and would affect our bodies. We could live on it for short periods of time though, but with plenty of exercise. BML-0798c- 0/10 as the gravity is way too low for our bodies to function properly. BML-0798D- 0/10 as the gravity is way too low for our bodies to function properly. EFFECTS OF GRAVITY ON THE BODY The gravity on Earth is 1g. It thought that humans could not live for long periods in conditions below 0.5g or above 1.5g as their body would be affected. EFFECTS OF LOW GRAVITY ON THE BODY Humans wouldn’t be able to live on a planet with very low gravity. Some people say that there are benefits of living with no gravity such as relief to back pain, poor circulation being improved in addition to with some surgeries becoming simpler to perform. This however, is not true as low gravity would cause its own problems. Bones would become brittle as they would be less dense. This would be because the bones would stretch and lengthen as there wouldn’t be a downward force on you lowering the limit of your growth. Astronauts have been known to have growth spurts as their bones as there is less calcium for a certain amount of bone, osteoporosis becomes more common. Low muscle density would occur as it would also be harder to be as active as less effort would be required to exercise – this would also affect that strength of the heart. This can mean that when astronauts return to Earth their hearts are weaker. Everyday tasks to become difficult for people as things would float off. It would also be harder to become active and fit on a low gravity planet as less effort is required to exercise. Immune systems would be weakened, leading to higher risk of infection and disease. EFFECTS OF HIGH GRAVITY ON THE BODY The effects of very high gravity on the human body are unpredictable, as no person has ever experienced such conditions long term. 2.5g is the gravity on Jupiter and it is thought that people wouldn't be able to survive as their bodies would be crushed from the constant pressure. Gravity of over 1.5g can also cause problems. Carrying around possibly double your body weight - so even if you have a low body mass you would seem unhealthier - can result in joint problems. High gravity has the opposite effect on the heart to low gravity so the heart would have to work harder which would be harmful to people with weak hearts. Blood pressure would increase to unhealthy levels so hearts would be put under a lot of pressure. Continuous strain on the heart and arteries would result in them being worn out quicker, shortening life spans. Blood vessel damage would become more common, therefore varicose veins would be more common. More effort needed to move about on the surface so your muscles and joints would be stronger and denser. DENSITY OF EXOPLANETS HOW TO WORK OUT THE DENSITY OF EXOPLANETS To work out the density of an exoplanet: mass of the planet/volume of the planet. We depend on the planet’s density to determine whether it is a solid or a gas planet. The easiest way to work out if it is a gas or a solid planet is by comparing its volume with its density. Gas planets –like Jupiter and Saturn- tend to be much larger than small rocky planets, like Earth. WHAT WE CAN TELL FROM DENSITY Therefore, we can work out that if a planet has a large volume but a small density, it is a gas planet. However if it has a small volume and a density that is large compared to its volume, we can assume that it is a ‘rocky’ planet. For example a planet with large volume and small mass would be a gas planet. This is because its volume is huge compared to its mass. However if a planet had small volume and large mass, we can assume that it is a ‘rocky’ planet as it has large mass compared to its volume. DIAGRAM TO SHOW THIS Here is a diagram to represent densities and what we can determine from them: This is the mass relative to Earth’s. DENSITIES OF THE EXOPLANETS FORMULA We worked out the densities relative to Earth’s instead. Density=mass/volume Volume=4/3πr3 Therefore, volume is proportionate to r3. Density= Mass (relative to Earth)/radius (relative to Earth)3 DENSITIES OF THE EXOPLANETS BML-0798a 4/23=4/8=1/2=half Earth’s density BML-0798b 27/253=0.0017=0.17% of Earth’s density BML-0798c 25/493=0.00021=0.021% of Earth’s density BML-0798d 4/163=0.00098=0.098% of Earth’s density DENSITIES OF THE EXOPLANETS RATINGS BML-0798a would be a solid planet because it is half of Earth’s density, but it does not have the density to have an iron core like Earth, which means no magnetosphere or ‘central heating’ to heat us up again if we went into an ice age, like what happens on Earth. However, it would be habitable. 7/10 BML-0798b would be a gas planet because it has a very small density, so it would be uninhabitable. 0/10 BML-0798c would be a gas planet because it has a very small density, so it would be uninhabitable. 0/10 BML-0798d would be a gas planet because it has a very small density, so it would be uninhabitable. 0/10 ATMOSPHERE ROLES OF THE ATMOSPHERE The atmosphere is very important to human life. Not only does it trap the very air we breathe, it protects us from harmful radiation from the sun like gamma rays and ultraviolet light. Mars has a very thin atmosphere, which is why we couldn’t live on its surface like on Earth. THE MAGNETOSPHERE However, it did used to have an atmosphere. The atmosphere acts as a shield to us, but the atmosphere itself needs a shield. We have a magnetosphere, which is why we have a magnetic field. This magnetosphere protects the atmosphere from intense solar wind and high-energy particles emitted during solar storms which could otherwise blow away the atmosphere, like it did on Mars. NASA has found evidence to suggest that Mars lost its magnetic field nearly 4 billion years ago, not long after its formation. Without the protection of the magnetosphere, the solar wind and storms could have scoured Mars’ atmosphere and eliminated it entirely over about a billion years. So, we’re hoping that the exoplanets have magnetospheres, otherwise we’re going to live underground for a very long time, and satellites like we have on Earth are going to be near impossible to send up. ATMOSPHERE Scientists can tell which elements are in the atmosphere by using a spectrograph, which splits up light passing through the atmosphere into the spectrum. Different chemicals in the planet's atmosphere absorb some of the star's light, causing black lines on the spectrum, called absorption lines. These lines can be shown in a graph as well which is called a Spectral Graph. Below is an example of a planet with sodium in its atmosphere. ELEMENTS NEEDED FOR HUMAN SURVIVAL SOME ELEMENTS IN OUR ATMOSPHERE Oxygen is needed so that our cells are able to respire and change it into carbon dioxide and glucose. Water is needed as it makes up 75% of our bodies and keeps us hydrated. Carbon Dioxide is needed as plants use it to produce oxygen (photosynthesis) which we then use to produce carbon dioxide, so it is essential for both humans and plants. BML-0798A This planet is one that we could probably live on as it has water, oxygen and carbon dioxide which are all elements that humans need to survive. No other elements are mentioned, but these three are in suitable amounts. BML-0798B This planet is also one that we could probably live on as it has water, oxygen and carbon dioxide which once again are elements that humans need to survive. No other elements are mentioned, but these three are in suitable amounts. BML-0798C This planet could also be habitable as it has three elements needed for humans to live herewater, oxygen and carbon dioxide. No other elements are mentioned, but these three are in suitable amounts. BML-0798D This planet is not habitable as it has no water, although it has Oxygen and Carbon Dioxide. Water is very important to life on Earth because: •Our bodies are 80% water. •Water serves as a lubricant in our digestive system. •It helps to regulates our body temperature through sweating, which then causes evaporation which lowers our body temperature as (temperature=average energy of particles). •Plays a vital everyday role in washing, etc. Here are some more roles of water. ROLES OF LIQUID WATER IN LIFE Water is mostly in ice form in the universe, but is needed as a liquid to play a role in life. Life (probably) needs a solvent that has to be active, flexible and diverse in its roles. Water is currently the only known substance that can do this. Water is obviously essential for human life, as mentioned before. But what about alien life forms? Alien life forms could probably not have adapted to life without water. Without water, life simply cannot be sustained. Water is what lubricates the workings of the cell, transports the materials and molecular machinery from one place to another and facilitates the chemical reactions that keep us going. It takes away waste and brings nutrients to where they are needed. Without water, plants would die. Some cells can avoid death if their water is extracted, but then they shut down utterly until rehydrated. BEST PLANET ATMOSPHERE •BML-0798b has the best atmosphere for humans as it is the closest to Earths spectrograph although it is still quite possible for human life to exist on BML-0798a and BML-0798c, as they contain the right elements. VOLATILITY HOW VOLATILE ARE EXOPLANETS? When discovering planets, volatile refers to a group of chemical elements and compounds that have a low boiling point – for example nitrogen, water, helium, hydrogen and all those elements and compounds associated with planets or moons crusts and/or atmosphere’s. If an exoplanet has a lot of elements or compounds with high boiling points – which are called refractory substances – the planet is less volatile. HOW VOLATILE ARE EXOPLANETS? Certain elements or compounds that have an exceptionally low freezing point, such as hydrogen and helium are classed as gases, whereas elements and compounds with boiling points of over 100K are referred to as ices. This can be confusing, as the terms ‘gas’ and ‘ice’ in this context can refer to solids, liquids and gases – for example, Jupiter and Saturn are called Gas Giants, when the majority of the gas is actually extremely hot, highly dense fluid that gets even more dense the closer you get to the centre of the planet. HOW VOLATILE ARE EXOPLANETS? So, if an exoplanet contains lots of volatiles at the right amount – which is hard to come by - the planet itself is classed as habitable . You can tell which elements and compounds are in an atmosphere by the use of spectrographs and examining absorption lines – certain colours in the spectrum being absorbed by elements or compounds in the atmosphere. So far, Earth is the only planet in the entire universe we have found that has the perfect amount of volatiles for sustaining life, but scientists and astronomers still hope to find an exoplanet that fits the criteria and could be habitable. HUMAN LIMITATIONS HUMAN LIMITATIONS- SLEEP We as humans need sleep to survive. Without it we become irritable and eventually it starts to be a difficulty to do tasks such as: think, recite the alphabet, seeing, hearing and talking. This is because your body uses sleep to restore your energy which you may have used during the day. It also helps you recover from injuries and illness'. Many people (if not all) find it easier to sleep in the dark (like at night). If it is needed for us to leave Earth then we will need to find a planet that spins on it's axis at a similar rate to Earth otherwise we may find that days are too long for us with too little amounts of night where we can sleep. Or the days may be too short for us leaving us in darkness for longer than we would be on Earth. Eventually, we would evolve to these different conditions, but it would take time and a lot of getting used to on the behalf of all humans. This could limit the amount of exoplanets available to us, unless we decide to take the risk. HUMAN LIMITATIONS- G-FORCE A limitation of humans is G-force. To get to faster speeds whilst travelling to a different planet we, as humans will need to be able to withstand G-force. This is because many exoplanets are quite far away, so we will need to travel incredibly fast to get to these planets because supplies can only get us so far. G-force is the force caused by the acceleration of an object. With training humans can reach up to 9G (the measurement of G-force), before losing consciousness. Prior to this we would have lost our colour sight. However, without training most people would only be able to stand around 5G. BEATING G-FORCE Recently though, scientists have used the same method that occurs naturally in giraffes when they stoop to drink. Logically thinking, their blood should rush to their head. However, it doesn’t because this would harm the creatures. Using the same method that stops blood rushing to the head of a giraffe, scientists have managed to create a suit which is then worn by humans and this can help us stay conscious at 9G. The person doing the experiment also did a Rubix Cube to prove that he could still see in colour. Here is a video of this experiment from the BBC 1 show: "Richard Hammond's Miracles of Nature“, with our own commentary. For a video of g-force, open ‘G-force video’. SURFACE AREA SURFACE AREA The surface area of a planet tells us how much space there is and so whether it would be sufficient for our population. A very large surface area also makes it more likely that a planet is a gas giant however we can check this for certain by measuring volume and density. Assuming that planets are perfectly spherical (which obviously in most cases they’re not – the earth has different levels and bulges in places) we can calculate the surface area using the equation 4πr2 where the radius is compared to that of the earth with the earth’s radius being 6 378.1 kilometres. All of these planets have a larger surface area than the earth however this does not mean that they will have larger habitable areas as they may have very large places of extreme temperatures and much land covered by water. SURFACE AREA CALCULATIONS Earth - 4π*6378.12 = 511,000,000 km2 (3sf) BML-0798a – 4π*(2*6378.1)2 = 2,040,000,000 km2 (3sf) ^roughly 4 times that of the earth because the radius is twice the size and 22 = 4 BML-0798b – 4π*(25*6378.1)2=320,000,000,000 (3sf) ^roughly 625 times that of the earth because the radius is 25 times the size and 252 = 625 BML-0798c - 4π*(49*6378.1)2=1,230,000,000,000 (3sf) ^roughly 2401 times that of the earth because the radius is 49 times the size and 492 = 2401 BML-0798c - 4π*(16*6378.1)2=131,000,000,000 km2 (3sf) ^roughly 256 times that of the earth because the radius is 16 times the size and 162 = 256 DISTANCE AND TRAVEL WHAT IS A LIGHT YEAR? The star in the solar system BML–0798 is 11.4 light years from earth. Although the term ‘year’ can be defined in a number of different ways, the International Astronomical Union regards a year as a Julian year, i.e. 365.25 days, making the total number of seconds in a year 31,557,600. The speed of light, unlike the year, is a universal constant measuring at 299,792,458 metres per second. DISTANCE This means that the length of a light year (a unit of distance – not time – denoting the distance light can travel in a year) can be calculated as: 31557600*299792458 = 9,460,730,472,580,800 metres in a light year This means that 11.4 light years is: 9,460,730,472,580,800*11.4 = 107,852,327,387,421,120 metres The speed of light is, according to the theory of special relativity, the maximum speed at which all energy and matter in the universe can travel. There is little friction in outer space so most engines are, in theory, only limited by the speed of light however current engineering factors (such as the availability, weight and strength of fuel) prevent today’s spacecraft from travelling long distances at high speeds. In order for anything with a mass to reach this phenomenal speed it would require infinite energy and so, although theoretically it is possible to reach up to 99.999...% of the speed of light, to actually travel at the total speed would require more than the total amount of energy in the universe. HOW LONG WOULD IT TAKE? This means that if we travelled at 10% of light speed, it would take 114 years to get to the star of the BML-0798 solar system. This is a little optimistic however, as rockets today can only travel at tiny fractions of the speed of light meaning that we need much engineering development in order to travel to the galaxy BML–0798 in 12.54 years. 1% would be unlikely, but more reachable. At 1% of speed of light, it would take 1,140 years to get there. With current technology, a much more feasible speed would be 0.1% of the speed of light, it would take 11,400 years to get there. The question is: would we last that long on the spaceship? Technology is going to have to move faster so we don’t have to worry about that. TECHNOLOGY Telescopes TYPES OF TELESCOPES Optical telescopes can be used on Earth and in space. An example of a huge optical telescope in space is the Hubble Space Telescope through which astronomers can look out across the Universe without the distortion of light by the Earth's atmosphere. The first optical telescope was created 400 years ago, while the other kinds of telescopes were invented in the 20th century. TYPES OF TELESCOPES Radio telescopes also can be used on Earth or in space. An example of a radio telescope on Earth is the Very Large Array of 27 antennas lying across New Mexico. Radio signals received from deep space received by the VLA are combined electronically to create a virtual antenna which is 22 miles across. TYPES OF TELESCOPES Infra-red telescopes are affected by Earth's atmosphere. They are operated at high altitudes, as they must be above water vapour in the atmosphere, or else they can operate in space. They are most often found on mountaintops. The large Space Infrared Telescope Facility (SIRTF) was launched in 2003. Hubble also observes in infrared light. Unfortunately, it is very hard for exoplanets such as the ones we have been studying to be observed by telescopes, as their light is so much fainter than their parent star. Fewer than 5% of exoplanets are observed directly known as November 2011. For this reason, although useful for explorations closer to home, telescopes aren’t very often used as a way of distinguishing exoplanets. MORALS Should we even leave Earth? SHOULD WE EVEN LEAVE? Some people believe that we shouldn’t even leave. These views are in the minority, but are still prevalent. AGAINST LEAVING We all have these grand ideas of moving to another planet when ours has either run out of resources that we need to survive, or we have destroyed the planet ourselves, but have we ever stopped to think about how other life forms may react to us wanting to join their civilisation. We have all had the thought that any other intelligent life would invade our own planet and that we would defend it against them, but have we ever thought that maybe alien life forms have seen us destroy our own planet and therefore do not want to share their planet with us. Maybe the planet we choose to go to does have alien life forms on it and they themselves are running out of supplies. Is it fair to take what little they have to support our own needs? FOR LEAVING Then again, many people would help others if and when they can. Surely it would be unfair for alien life forms to turn us away, even if they had limited resources, because they should remember that one day they will be in the same position as we were. With us we would take technology and life from Earth (plants and other animals). We could teach other life forms about this technology (provided that they are not as technologically advanced as us) and about what we have discovered and found out through science. Also, culture could be shared between us. This may help them, so the idea of going to another planet is not completely selfish as we, in return would probably help them as much as we can in the circumstances. CONCLUSION WHY LEAVE? Despite all the threats to our planet, people may not wish to leave – choosing to spend their last days in their home instead of sacrificing their quality of life so that future generations can survive. The fact that the threat is so distant – several lifetimes away – also makes a desire to stay more likely because people themselves will not be affected-their descendants will. The habitability of the planet, though likely, is not certain until we arrive and our journey will force an entire society into a very small space. We think that it would be against your human rights for us to force you to leave your home however we hope that people will think of the future generations and join us in our mission. TABLE OF RESULTS Exoplanet Habitable zone rating /10 Gravity rating /10 Density Atmosphere rating rating /10 /10 Average rating /10 BML-0798a 10 10 7 9 9 BML-0798b 10 7 0 10 6.75 BML-0798c 0 0 0 9 2.25 BML0798d 0 0 0 0 0 THE BEST EXOPLANET From the table of results, it’s clear that BML-0798a is the best exoplanet to live on. Humans could survive well on there- provided that we ever get there. With the Vogons due to arrive in 350 years, the question is: What now? THANK YOU FOR WATCHING