This preview shows page 1-2-3-4-5-6-7-49-50-51-52-53-54-55-98-99-100-101-102-103-104 out of 104 pages.
Astronomy 101 The Solar System Tuesday, Thursday 2:30-3:45 pm Hasbrouck 20 Tom Burbine [email protected] CourseOffice HoursHomeworkClass AveragesSlide Number 6FinalFormulas you may need to knowMore FormulasIntelligent LifeRadioFermi’s ParadoxFermi’s ParadoxReason for questionExplanationExplanationExplanationExplanationExplanationFermi’s paradoxSlide Number 21JupiterProbes to JupiterJupiterSlide Number 25CloudsSlide Number 27Slide Number 28Slide Number 29Slide Number 30Galileo ProbeGreat Red SpotJupiter’s RingsSlide Number 34Jupiter has four ringsSlide Number 36Slide Number 37Voyager 1 and 2Grand TourVoyager 2Voyager 1Voyager Golden RecordSlide Number 43Pioneer 10 and 11 Plaques (1972)SaturnSaturnRingsRoche LimitSlide Number 49Cassini-HuygensUranusUranusSlide Number 53AtmosphereUnusualProbablyUranus’ SatellitesSlide Number 58NeptuneNeptuneGalileoSlide Number 62Great Dark SpotGreat Dark Spot has disappearedNeptune’s RingsShoemaker-Levy 9Roche LimitWhy is the Roche Limit important?Slide Number 69Slide Number 70Slide Number 71Has this happened before? GanymedeGanymede-EuropaSlide Number 74Slide Number 75SatellitesSimon Marius (1573-1624)Slide Number 78GalileoGalileo spacecraftSagan’s Criteria for Life (From measurements of Earth by Galileo)DensitiesIoIoSlide Number 85Slide Number 86Slide Number 87Slide Number 88EuropaEuropaSlide Number 91Slide Number 92Slide Number 93Slide Number 94EuropaGanymedeGanymedeSlide Number 98Slide Number 99Slide Number 100CallistoCallistoSlide Number 103Any Questions?Astronomy 101The Solar SystemTuesday, Thursday2:30-3:45 pmHasbrouck 20Tom [email protected]• Course Website:– http://blogs.umass.edu/astron101-tburbine/• Textbook:– Pathways to Astronomy (2nd Edition) by Stephen Schneider and Thomas Arny.•You also will need a calculator.Office Hours• Mine• Tuesday, Thursday - 1:15-2:15pm•Lederle Graduate Research Tower C 632• Neil• Tuesday, Thursday - 11 am-noon • Lederle Graduate Research Tower B 619-OHomework• We will use Spark•https://spark.oit.umass.edu/webct/logonDisplay.dowebct• Homework will be due approximately twice a weekClass Averages• For people who took all 4 tests:• Class average is 81• Grades range from a 98.5 to a 55.4•Scores will go up when the lowest exam grade is dropped after the final• A (92.50 – 100)• A- (89.50 – 92.49)• B+ (87.50 – 89.49)• B (82.50 – 87.49)• B- (79.50 – 82.49)• C+ (77.50 – 79.49)• C (72.50 – 77.49)• C- (69.50 – 72.49)• D (59.50 – 69.49)• F (below 59.49)Final• Cumulative• Monday - 12/14 • 4:00 pm•Hasbrouck 20• Review Session• Sunday -12/13• 3:00 pm• Hasbrouck 134Formulas you may need to know• p2= a3• F = GMm/r2• F = ma• a = GM/r2• Escape velocity = sqrt(2GM/r)• T (K) = T (oC) + 273.15• c = f*λ• E = h*f• KE = 1/2mv2• E = mc2• Density = mass/volume• Volume = 4/3πr3More Formulas• Power emitted per unit surface area = σT4• λmax(nm) = (2,900,000 nm*K)/T•Apparent brightness = Luminosity4π x (distance)2Intelligent Life• Intelligent life that we can detect is usually defined as life that can build a radio telescopeRadio• Transmitting information over radio waves is very cheap• uses equipment that is easy to build• has the information-carrying capacity necessary for the task • The information also travels at the speed of light.Fermi’s Paradox• Where are they?Fermi’s Paradox• Why have we not observed alien civilizations even though simple arguments would suggest that some of these civilizations ought to have spread throughout the galaxy by now?Reason for question• Straightforward calculations show that a technological race capable of interstellar travel at (a modest) one tenth the speed of light ought to be able to colonize the entire Galaxy within a period of one to 10 million years.Explanation• Interested in us but do not want us (yet) to be aware of their presence (sentinel hypothesis or zoo hypothesis)Explanation• Not interested in us because they are by nature xenophobic or not curiousExplanation• Not interested in us because they are so much further ahead of usExplanation• Prone to annihilation before they achieve a significant level of interstellar colonization, because: (a) they self-destruct (b) are destroyed by external effects, such as: (i) the collision of an asteroid or comet with their home world (ii) a galaxy-wide sterilization phenomenon (e.g. a gamma-ray burster(iii) cultural or technological stagnationExplanation• Capable of only interplanetary or limited interstellar travel because of fundamental physical, biological, or economic restraintsFermi’s paradox• The Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations.• http://en.wikipedia.org/wiki/Fermi_paradoxJupiter• Largest planet– Mass - 1.899×1027kg (317.8 Earths)– Jupiter is 2.5 times more massive than all the other planets combined • Mean density - 1.326 g/cm3• Equatorial diameter - 142,984 km (11.209 Earths)Probes to Jupiter• Pioneer 10 – 1973• Pioneer 11 - 1974• Voyager 1 – 1979• Voyager 2 - 1979 • Ulysses - 1992 • Galileo – 1995 - Orbiter• Cassini - 2000Jupiter• Jupiter's atmosphere is composed of ~81% hydrogen and ~18% helium.• Jupiter probably has a core of rocky material amounting to something like 10 to 15 Earth-masses.• Above the core lies the main bulk of the planet in the form of liquid metallic hydrogen. This exotic form of the most common of elements is possible only at pressures exceeding 4 million bars– 1 bar ≈ standard atmospheric pressure at sea level on Earth.• Jupiter is composed – relatively small rocky core– surrounded by metallic hydrogen– surrounded by liquid hydrogen– surrounded by gaseous hydrogen.Clouds• clouds of ammonia (NH3), methane (CH4), ammonia hydrosulfide (NH4HS)• zone for the light stripes• belt for the dark stripes• http://en.wikipedia.org/wiki/Cloud_pattern_on_Jupiter• The differences in colors are caused by slight differences in chemical composition and temperature•http://zebu.uoregon.edu/~imamura/121/lecture-13/vjupitr2.movGalileo ProbeGreat Red Spot• A particularly violent storm, about three times Earth's diameter, is known as the Great Red Spot, and has persisted through more than three
View Full Document
Unlocking...