The Physics of UFOs Kevin Pitts University of Illinois

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1 The Physics of UFOs Kevin Pitts University of Illinois 2-Nov-12 World of Science - UFOs 1

2 Why UFOs? It all starts at Fermilab 2-Nov-12 World of Science - UFOs 2

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lie detectors, climate change, creationism, Last semester we performed extrasensory perception

8 Phys 192: Science & Pseudoscience What is good science? bad science? pseudoscience? Topics covered Alternative medicine, UFOs, ghosts, cold fusion, statistics, logical fallacies, lie detectors, climate change, creationism, Last semester we performed extrasensory perception experiments, all results negative! This semester, we re making videos! 2-Nov-12 World of Science - UFOs 8

9 Things aren t always as they seem

10 A Face On Mars Credit: The Viking Project, NASA APOD: 1998 April 6 2-Nov-12 World of Science - UFOs 10

11 The Face on Mars Credit: NASA,Viking Project, APOD: 1995 July 22 2-Nov-12 World of Science - UFOs 11

12 Mars Express Close-Up of the Face on Mars APOD: 2006 September 25 2-Nov-12 World of Science - UFOs 12

13 Polling Numbers Gallup In your opinion, are UFO s something real, or just people s imaginations? Real just people s imagination don t know 48.5% 31.0% 20.6% Gallup Do you think that UFO s have ever visited the earth in some form, or not? Yes no don t know 45.1% 40.0% 15.9% In this same poll, 71% of those surveyed believe that the government knows more about UFOs than it is telling. 2-Nov-12 World of Science - UFOs 13

14 Extraordinary claims require extraordinary evidence Dr. Pitts, I noticed that you will be presenting a lecture entitled The Physics of UFOs. I am not attending the lecture, but would like to know if you have written an article on this topic and, if so, whether it is available for people to read. On the basis of what I have read, there seems to be a fair amount of evidence based on (a) reports from highly reliable witnesses (including former military people, police officers, and pilots) (b) physical trace findings, and (c) radar recordings, which support the hypothesis that at least some reported UFOs are highly technologically advanced craft that may have an extraterrestrial origin. The Extraterrestrial Hypothesis seems plausible for explaining at least some reported UFO sightings. No testimony is sufficient to establish a miracle, unless the testimony be of such a kind that its falsehood would be more miraculous than the fact which it endeavors to establish -David Hume s maxim 2-Nov-12 World of Science - UFOs 14

15 Extraordinary claims require extraordinary evidence -Carl Sagan

16 Basic question Questions about UFOs Is there life anywhere other than Earth? If yes: Is there intelligent life anywhere other than Earth? If yes: Could we communicate? Could they come and visit us? Could we visit them? Have we communicated? Have we visited? 2-Nov-12 World of Science - UFOs 16

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18 Questions/Topics 1. Distances 2. Nature s speed limit 3. Acceleration 4. Radiation 5. Is there anybody out there? 6. How would they know we re here? 7. Making contact 2-Nov-12 World of Science - UFOs 18

19 Speed of light 186,000 miles/second = 299,792,458 m/s 7x around Earth in one second Sun to Earth in about 8 minutes Earth to Mars in 3 22 minutes 2-Nov-12 World of Science - UFOs 19

20 Distance Scales Measurement unit: 1 light-year = distance light travels in one year 1 ly = 5,843,190,000,000 miles 6 trillion miles It takes Earth about years to travel 1 ly around the Sun 2-Nov-12 World of Science - UFOs 20

21 Mars Rover Landing Landing called 7 Minutes of Terror 2-Nov-12 World of Science - UFOs 21

22 The Milky Way Galaxy 100,000 light years You are here (approximately) 2-Nov-12 from Atlasoftheuniverse.com World Science - UFOs 22

23 Distances Nearest star is Alpha Centari, 4.3 ly away. About 14,000 stars (3500 visible) within 100 ly Sun about 25,000 ly from center of milky way. To travel to planets orbiting other stars, aliens (or humans) need 1. to travel near the speed of light 2. to be able to handle long-duration flights even with these criteria, can probably only visit a few nearby stars. 2-Nov-12 World of Science - UFOs 23

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Nature s Speed Limit In 1905, Albert Einstein published the Special Theory of Relativity One consequence of the theory is the famous equation: E = mc 2

25 Nature s Speed Limit In 1905, Albert Einstein published the Special Theory of Relativity One consequence of the theory is the famous equation: E = mc 2 Important for this discussion is another constant: no information or object can travel faster than the speed of light. 2-Nov-12 World of Science - UFOs 25

26 Testing the speed limit protons circulate around accelerator rings Speed=0.99c=184,500mi/sec Speed= c=185, mi/sec reminder: speed of light c = 186,000 mi/sec Fermilab, Batavia, IL 2-Nov-12 World of Science - UFOs 26

High Speed travel Fastest manned object: Apollo 10: speed 25,000 mph = 0.

27 High Speed travel Fastest manned object: Apollo 10: speed 25,000 mph = c Fastest man made object Helios 2 space probe: 158,000 mph = c This speed was attained by orbiting the sun, not through rocket propulsion. 2-Nov-12 World of Science - UFOs 27

28 Rockets Rockets work by Newton s 3 rd Law Burn the fuel, it gets pushed out of the nozzle. The fuel pushes back on the rocket, accelerating it. Good news This works even in outer space Bad news Have to carry your fuel with you 2-Nov-12 World of Science - UFOs 28

29 Acceleration Something accelerating at 1g is speeding up at 10 m/s 2 At 1 second: speed 10 m/s At 2 seconds: speed 20 m/s At 3 seconds: speed 30 m/s F-16 pilots can withstand ~6g s for a few seconds. (link) People might be able to withstand 2-3g s for an extended period of time. Space Shuttle "Guidance also governs the main engine throttle command so that acceleration does not exceed 3 g's. The main engines are throttled down at approximately seven minutes 40 seconds into the mission to maintain 3 g's for physiological and structural constraints." 2-Nov-12 World of Science - UFOs 29

30 Acceleration Imagine we have a spaceship that can reach a speed of 0.75c This is 20,000 times faster than Apollo We start at rest on Earth (or near Earth) but we can only accelerate at 3g s or else we ll kill all of the passengers. How long does it take for our spaceship to reach a speed of 0.75c? Answer: 116 days We need enough fuel to accelerate at 3g s continuously for 4 months! Don t forget, we must decelerate at the same rate. So we need to fire our breaking rockets 4 months prior to when we want to stop. 2-Nov-12 World of Science - UFOs 30

31 We need Anything prohibitive so far? Radically new technology to accelerate and decelerate our space ship The ability to undergo long duration space flight (decades to get to the nearest star) What about dangers during space flight? Radiation! 2-Nov-12 World of Science - UFOs 31

32 National Research Council, 2008 At the present time, given current knowledge, the level of radiation astronauts would encounter would not allow a human crew to undertake a Mars mission and might also seriously limit long-term Moon activity. International Space Station astronauts receive a radiation dose that is 27 times higher than we receive on Earth s surface. The ISS is still protected by Earth s magnetic field and upper atmosphere. 2-Nov-12 World of Science - UFOs 32

33 Radiation Earth s atmosphere and magnetic field protect us from cosmic radiation. 2-Nov-12 World of Science - UFOs 33

34 Radiation Radiation would be sufficient to kill humans in long duration space flight, unless an acceptable shielding method was developed. Perhaps other beings might be less susceptible to radiation effects. 2-Nov-12 World of Science - UFOs 34

35 Questions/Topics 1. Distances 2. Nature s speed limit 3. Acceleration 4. Radiation 5. Is there anybody out there? 6. How would they know we re here? 7. Making contact 2-Nov-12 World of Science - UFOs 35

36 Galaxies Our sun is a small star toward the outside of the galaxy, the Milky Way (a spiral galaxy) containing approximately 200,000,000,000 stars (2 x ) A few others (e.g. Andromeda) visible to naked eye Telescopes reveal many galaxies, each ~ stars Andromeda Spiral Galaxy m100 2-Nov-12 World of Science - UFOs 36

37 The Milky Way Galaxy 100,000 light years You are here (approximately) 2-Nov-12 from Atlasoftheuniverse.com World Science - UFOs 37

Views from the Hubble Telescope Picture of an area of the sky (the size of a grain of sand held at arm s length) in which there are no stars visible to the naked

38 Views from the Hubble Telescope Picture of an area of the sky (the size of a grain of sand held at arm s length) in which there are no stars visible to the naked eye! Shows visible stars in the Milky Way and distant fuzzy looking galaxies Estimate: ~10 11 =100 billion galaxies in the universe 2-Nov-12 World of Science - UFOs 38

39 Summary About stars per galaxy 2 to 4 x in the Milky Way About galaxies in the universe So we have about: x = = 100,000,000,000,000,000,000,000 stars in the universe. More stars in the universe than grains of sand on Earth Universe is dominated by light elements (H, He, Li) but there are plenty of heavy elements that have been produced by supernovae. 2-Nov-12 World of Science - UFOs 39

40 Question: How many Earth-like planets: Requirements: Good Places for Life Single star system (not binary) Star should be sunlike (similar to our sun) Must have planets Must have Earth-like planet Estimates (arguable, but you can change them!) ~50% are single star systems (not binary) ~10% are sunlike (similar to our sun) ~10% have planets ~10% have an Earth-like planet These two estimates are pretty solid. These two estimates are low, reality possibly much higher. 4x10 11 x 0.5 x 0.1 x 0.1 x 0.1 = 2x10 8 =200,000,000 Earthlike planets in the Milky Way galaxy alone!!! [low estimate] 2-Nov-12 World of Science - UFOs 40

41 How Would We Make Contact? Einstein says we can t travel faster than the speed of light. Experiments say he s right. This immediately limits the possibilities for space travel between solar systems that are light years apart. Milky Way is about 100,000 light-years wide What can travel at the speed of light? Electromagnetic waves! Light, x-rays, radio-waves. First contact with an intelligent life form would most certainly be through electromagnetic waves! 2-Nov-12 World of Science - UFOs 41

42 Electromagnetic spectrum All EM radiation travels at speed of light! 2-Nov-12 World of Science - UFOs 42

43 SETI Search for Extra Terrestrial Intelligence Scanning the sky for all electromagnetic frequencies Looking for non-random patterns indicating a deterministic source. Note: Humans have been broadcasting to the galaxy since the early 20 th century. Our electromagnetic waves now reach out some 80 lightyears away from us. Anyone farther than 80 light-years would not yet be able to see our broadcasts! About 14,000 stars within 100 light-years of us (= % of the Milky Way) For signals originating elsewhere, our sensitivity depends upon location on time. To see a civilization on the other side of the Milky Way, they needed to begin broadcasting 30,000 years ago! 2-Nov-12 World of Science - UFOs 43

44 How Would We Make Contact? First contact with an intelligent life form would most certainly be through electromagnetic waves! Allen Telescope array, part of SETI = Search for Extraterrestrial Intelligence Project Scanning the sky for all electromagnetic frequencies Looking for non-random patterns indicating a deterministic source. You can participate in SETI at Home (link) 2-Nov-12 World of Science - UFOs 44

45 How Would They Know We re Here? Humans have been broadcasting to the galaxy since the early 20 th century. Our electromagnetic waves now reach out some 80 lightyears away from us. Anyone farther than 80 light-years would not yet be able to see our broadcasts! About 14,000 stars within 100 light-years of us (= % of the Milky Way) For signals originating elsewhere, our sensitivity depends upon location on time. To see a civilization near the center of the Milky Way, they needed to begin broadcasting 25,000 years ago! 2-Nov-12 World of Science - UFOs 45

46 The Milky Way Galaxy 100,000 light years Our electromagnetic footprint is smaller than this dot! The rest of the galaxy has no idea that we are here! 2-Nov-12 from Atlasoftheuniverse.com World Science - UFOs 46

47 Sound channels and Roswell

48 Ocean depth Sound channels Waves will channel where the wave speed is lowest. Speed of sound In ocean, channel is about ½ mile in depth Atmospheric sound channel about 30 miles up 2-Nov-12 World of Science - UFOs 48

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52 Summary Is there life beyond Earth? We don t know. Has extraterrestrial life visited Earth? There is no credible evidence that it has. Extraordinary claims require extraordinary evidence. We have yet to see that evidence. If we make contact with another civilization, it will be by electromagnetic wave. 2-Nov-12 World of Science - UFOs 52

53 How would they know we re here? We are looking for exoplanets Planets that orbit stars other than our own Any in the Goldilocks zone? 2-Nov-12 World of Science - UFOs 53

54 UFOs? Have we been visited? 2-Nov-12 World of Science - UFOs 54

55 UFOs Question: Why are they always seen by untrained observers? Professional astronomers and astrophysicists observe the sky daily with sophisticated equipment have never observed an extraterrestrial spaceship. Question: Why hasn t anyone observed the electromagnetic footprint (radio waves, gamma rays, light, etc.) of an alien? The electromagnetic footprint would be here before the aliens would. 2-Nov-12 World of Science - UFOs 55

56 UFOs: Natural Explanation Some sources that might be misinterpreted: Approaching Aircraft (appear to hover) Unconventional Aircraft High Altitude Balloons Venus Artificial Satellites Reflections Off Clouds Optical Mirages Meteors Uncommon Atmospheric Phenomena (Aurora, Ball Lightning) Secret Military Objects Accidents 2-Nov-12 World of Science - UFOs 56

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The big bang (and it s aftermath) produced no element heavier than lithium (atomic

58 Material for Life Earth is teeming with elements: Nitrogen, hydrogen, oxygen, carbon, gold, iron, manganese, H uranium, silver, lithium Atomic # = # of protons The big bang (and it s aftermath) produced no element heavier than lithium (atomic number=3). Hydrogen, helium and lithium only.nothing heavier. 2-Nov-12 World of Science - UFOs 58

59 Heavy Elements Heavy elements are crucial for life. Carbon, oxygen, nitrogen, iron, potassium Where did the heavy elements come from? Normal stars (our sun) typically produce helium from hydrogen, but also produce some lithium and beryllium (Be, atomic #=4) Elements heavier than beryllium require a higher energy process to produce them a supernova. Supernovas occur at the end of a large star s life cycle. The stuff you are made of: carbon, oxygen, silicon, iron, etc. are supernova remnants! 2-Nov-12 World of Science - UFOs 59

60 Supernova Expels matter - all heavy elements in the universe (in you!) are formed in supernovae Remnant is a neutron star or black hole Radiates more energy than an entire galaxy for a brief period (months): Famous supernovae: 0 -- The Christmas Star?? in Crab Nebula, Recorded in China, in large Magellanic Cloud, seen by Kepler Pulsars (Neutron Stars) observed now as remnants of the 1054 and 1572 Supernovae! in Magellanic Cloud - remnants still observed 2-Nov-12 World of Science - UFOs 60

61 Does Life Develop? Experiments show that organic molecules form in conditions similar to the earliest stages of Earth s development. Carbon dioxide, water, nitrogen + energy (heat or lighting) Details of the mechanisms that bring single celled organisms (like amoeba) from the organic molecules are under study. Let s guess that there is only a 1% chance life will develop on an Earthlike planet. [This is probably a low estimate. The likelihood to develop life on an Earthlike planet is probably very high.] 2 x 10 8 Earthlike planets x 0.01 chance of developing life = 2 x 10 6 = 2,000,000 planets with life in the Milky Way. [this is still a low estimate] 2-Nov-12 World of Science - UFOs 61

62 Does Intelligence Develop? Large uncertainty. See Hobson textbook for a discussion. Art Hobson, Physics Concepts and Connections The Drake Equation attempt to account for the likelihood of intelligent life to develop, as well as the lifetime time scale. See Origins web site. 2-Nov-12 World of Science - UFOs 62

Details here 2009 Morristown Hoax The icing on

show UFO Hunters featured the Morristown UFO as

Bill Birnes, the lead investigator of the show

definitively that the Morristown UFO could not

63 Details here 2009 Morristown Hoax The icing on the cake came when the popular History Channel show UFO Hunters featured the Morristown UFO as their main story one week. Bill Birnes, the lead investigator of the show and the publisher of UFO Magazine, declared definitively that the Morristown UFO could not have been flares or Chinese lanterns. 2-Nov-12 World of Science - UFOs 63

Are We Alone? 17-Oct-13 Phys 192 Lecture 6 1

Are We Alone? 17-Oct-13 Phys 192 Lecture 6 1 UFO Detectives I saw a UFO about 3 years ago. Can you guess what I saw? 17-Oct-13 Phys 192 Lecture 6 2 Exercise Break into groups of 3 or 4 Nominate a scribe