Introduction to Astronomy - Compiled Lessons PDF

INTRODUCTION TO ASTRONOMY PRESENTED BY: MR. MIGUEL M. ARTIFICIO ASTRONOMY Astronomy is the study of EVERYTHING in the universe beyond Earth’s atmosphere.  WHY STUDY ASTRONOMY? To provided deeper understanding of the universe To advance technology Astrophysics, Astrobiology, Space...

INTRODUCTION TO ASTRONOMY PRESENTED BY: MR. MIGUEL M. ARTIFICIO ASTRONOMY Astronomy is the study of EVERYTHING in the universe beyond Earth’s atmosphere.  WHY STUDY ASTRONOMY? To provided deeper understanding of the universe To advance technology Astrophysics, Astrobiology, Space Technology, Space Weather, Ethno- Astronomy, Space and Astronomy Education, and many more.  WHAT ARE ITS IMPACTS? Discovery and insights Technological Innovation Science awareness Evolution of mankind  ANCIENT ASTRONOMY Where am I? Where did I COME from? Astronomy is as OLD as humanity itself. From the first man to walk the plains of Africa, to the migration of man all over the world.  GREEK CONTRIBUTIONS Eratosthenes – mathematician, astronomer, poet, geographer, and musician. GREEK CONTRIBUTIONS Computing Earth’s Circumference  GREEK CONTRIBUTIONS Claudius Ptolemy an astronomer, mathematician, and geographer Known for the geocentric model  GREEK CONTRIBUTIONS The Geocentric Model or “Earth- Centered Universe Model”  ISLAMIC CONTRIBUTIONS Al-Battani Islamic astronomer and mathematician Conducted accurate observations of the Sun, Moon, and catalogued 489 stars Calculated the tilt of Earth’s Axis  ISLAMIC CONTRIBUTIONS Al-Biruni Claimed the Earth rotated on its own axis Was also able to compute Earth’s circumference ISLAMIC CONTRIBUTIONS Star Name Meaning Aldebaran ‘The Follower’ Algol ‘The Ghoul’ Arrakis ‘The Dancer’ Deneb ‘Tail’ Fomalhaut ‘The Fish’s Mouth’ Rigel ‘Foot’ Thuban ‘Snake’ Vega ‘Stooping Eagle’ ‘The Hand of the Betelgeuse Giant’ ASTRONOMY DURING THE RENAISSANCE Advancements, Persecutions, and Paradigm Shifts  THE RENAISSANCE Nicolas Coppernicus Mathematician, astronomer, and a devout catholic. Proposed the Sun was at the center of the Universe.  THE RENAISSANCE The Heliocentric Model is a theory that places the Sun at the CENTER of the Solar System. It also maintains that the Earth revolves around the Sun.  THE RENAISSANCE Tycho Brahe Was a Danish astrologer, astronomer, and alchemist Conducted precise observations of astronomical objects Proposed alterations to the “Heliocentric Model”, with the other planets orbiting around the Sun, while it revolved around the Earth THE RENAISSANCE Hans Lippershey - invented spyglass in 1608 Controversy Other claimants of the invention Zacharias Jansen Jacob Metius The “spyglass” was used for magnifying far away objects.  THE RENAISSANCE Galileo Galilei – heard about the spy glass, and he built his own to observe the night sky. Discovered Sunspots, craters on the moon, Jupiter’s moons, Venus had phases like the moon, Saturn's “handles” or rings, and stars in the milky way  THE RENAISSANCE Sir Isaac Newton – designed his own telescope utilizing mirrors. The Newtonian Telescope Based on his observations, he had better success with his resolutions of astronomical objects. THE RENAISSANCE Newtonian Mechanics Newton’s Law of Motion First Law: A body stays at rest or in uniform motion unless acted upon by a force. Second Law: The net force on a body equals its mass times acceleration. Third Law: Forces between two bodies are equal in magnitude and opposite in direction.  THE RENAISSANCE Newtonian Mechanics Newton’s Gravitational Law - Every mass attracts every other mass with a force proportional to the product of their masses and inversely proportional to the square of the distance between their centers. Where: F = Gravitational Force G = Gravitational Constant = 6.67x10^-11 N.m^2/Kg^2 M = Mass R = radius THE RENAISSANCE Johannes Kepler German Astronomer Discovered three major Laws of Planetary Motion  THE RENAISSANCE Three Laws of Planetary Motion Planets move in elliptical orbits with the Sun as a focus A planet covers the same area of space in the same amount of time no matter where it is in its orbit A planet's orbital period is proportional to the size of its orbit (its semi-major axis)  THE RENAISSANCE Giordano Bruno was an Italian philosopher, poet, alchemist, astronomer, and cosmological theorist Suggested that the universe is infinite and many worlds are populated by various intelligent species ASTRONOMY DURING THE INDUSTRIAL AGE AND BEYOND A new frontier……………  THE INDUSTRIAL AGE William Herschel He discovered the planet Uranus, hypothesized that nebulae are composed of stars, and developed a theory of stellar evolution  THE INDUSTRIAL AGE Friedrich Bessel Discovered stellar parallax—the extremely tiny shift in the apparent position of a star when observed from opposite sides of the Earth's orbit. THE INDUSTRIAL AGE  THE INDUSTRIAL AGE James Clerk Maxwell A physicist, Theory of electromagnetism Maxwell’s field equations Determined that Saturn’s rings are a composition of small orbiting bodies  THE INDUSTRIAL AGE Edwin Hubble is renowned for determining that there are other galaxies in the Universe beyond the Milky Way, and for observing that the universe is expanding at a constant rate.  THE INDUSTRIAL AGE Albert Einstein Special Theory of Relativity E=mc^2 General Theory of Relativity THE INDUSTRIAL AGE Max Planck The father or Quantum Physics Planck Constant  THE INDUSTRIAL AGE Carl Sagan Astronomer, scientist, and a famous science communicator. “The universe is a pretty big place. If it's just us, seems like an awful waste of space.”  THE INDUSTRIAL AGE Stephen Hawking Theoretical physicist, and cosmologist Famous for his work on Black Holes “Hawking Radiation” COMMON MISCONCEPTIONS IN ASTRONOMY MISINFORMATION, MISCONCEPTIONS……… MISCONCEPTION # 0 Astronomy vs Astrology MISCONCEPTION # 1 The Sun is not a star? MISCONCEPTION # 2 Moon has phases because of Earth’s shadow? MISCONCEPTION # 3 Dark side of the moon? MISCONCEPTION # 4 Stars twinkle? MISCONCEPTION # 5 Earth’s season is caused by its distance to the Sun? MISCONCEPTION # 6 Meteors, meteoroids, meteorites? MISCONCEPTION # 7 Pluto is a planet? MISCONCEPTION # 8 Earth is flat? MISCONCEPTION # 9 The Big Bang Theory was an explosion? MISCONCEPTION # 10 The Sun will turn into a black hole? MISCONCEPTION # 11 Black Holes = Space vacuums? MISCONCEPTION # 12 Light year as a measurement of time MISCONCEPTION # 13 Parsec is a measurement of speed? MISCONCEPTION # 14 The North star is the brightest star? MISCONCEPTION # 15 There is no gravity in space? MISCONCEPTION # 16 Big dipper is a constellation? MISCONCEPTION # 17 Space is an empty vacuum? AND MANY MORE!!!  LESSON 3: SCIENTIFIC NOTATIONS AND BASICS TO ASTRONOMY COMPUTATIONS Presented by: Miguel M. Artificio Introduction to Astronomy  WHY?? Consistency and Clarity Accurate Computations and Measurements Uniformity in Interpretation  EXAMPLE ,  EXAMPLE.  EXAMPLE. EXAMPLE EXAMPLE  IMPORTANT UNITS In the context of time: In the context of distance: 1 Second (sec) – Basic unit of time; 1 meter (m): 100 cm, 1000 mm, 1.09 yd; 1/3.155694x10^7 of a tropical year 3.28 ft; 39.4 inches 1 Hour (hr) – 3600 seconds 1 kilometer (km): 1000 m; 0.62 miles 1 inch (in): 2.54 cm 1 Day – 84,400 seconds 1 foot (ft): 0.305 m 1 mile (mi): 1.61 km; 1609 m  IMPORTANT UNITS In the context of Mass In the context of Velocity In the context of Acceleration 1 meter/second (m/s): 3.6km/hr 1 gram (g) : basic unit of Gravitational Acceleration at mass Earth’s Surface 9.8 In the context of Temperature meter/second^2 1 kilogram (kg) : 1000g Celsius to Kelvin: K = C + 273.15 Kelvin to Celcius: C = K - 273.15 Fahrenheit to Celcius: C = (F-32) (5/9) Celsius to Fahrenheit: F = C(9/5) + 32 Fahrenheit to Kelvin: K = (F-32) (5/9) + 273.15 Kelvin to Fahrenheit: F = (K-273.15) (9/5) + 32  RELEVANT UNITS AND CONSTANTS FOR ASTRONOMY 1 Solar Mass = 1.989 x 10^30 kg 1 Solar Radius = 695,700 km 1 Earth Mass = 5.997 x 10^24 kg 1 Astronomical Unit (AU) = 1.49598 x 10^8 km 1 Light-Year (LY) = 9.6460x10^12 km 1 Parsec (pc) = 206,265 AU; 3.26 LY; 3.086 x 10^13 km Speed of Light = 299 792 458 m/s Average Temperature of the Universe = 3 Kelvins  RELEVANT CONSTANTS Gravitational Constant = Electron Volt = 1.602176487(40)×10−19J eV Boltzmann Constant = 1.380649 x 10^-23 J/K  CONT.. TELESCOPES, AND THE CELESTIAL NAVIGATION THROUGH THE CELESTIAL SPHERE INTRODUCTION TO ASTRONOMY PRESENTED BY: MIGUEL M. ARTIFICIO, MSC LIGHT PATH Is a path between two nodes in an optical network between which light passes through unmodified REFRACTING TELESCOPE REFLECTING TELESCOPE COMPOUND TELESCOPE (SCHMIDT- CASSEGRAINE) Flat Corrector Plate/ Flat Lens COMPOUND TELESCOPE (MAKSUTOV- CASSEGRAINE) Concave Corrector Plate / Concave Lens THE CELESTIAL SPHERE is an imaginary sphere with the earth at its center. Embedded within the sphere are the stars, planets, constellations, etc.. THE CELESTIAL SPHERE Celestial Poles: NCP North Celestial Pole (NCP) South Celestial Pole (SCP) These are points in the Celestial Sphere that lie above Earth’s North and South Poles. SCP  NORTH POLE AND SOUTH POLE? Geographic North Pole or True North - The North Pole is the point at the very top of Earth’s axis of rotation. It is the northernmost point on Earth’s surface, located at 90° latitude north. Geographic South Pole or True South - The South Pole is the point at the southernmost tip of Earth's axis of rotation, located at 90° south latitude. Magnetic North - is the point on Earth's surface where the planet's magnetic field points vertically downwards, which is the direction a compass needle points. Magnetic South - is the point on Earth’s surface where Earth's magnetic field points vertically upward, which is where a compass needle points south. THE CELESTIAL SPHERE Polaris Consequently, the star Polaris lies very close NC to the North Celestial Pole. Hence, it is P called a “Polar Star” or “The Northern Star” SC THE CELESTIAL SPHERE Celestial NCP Equator (CE) It is a circle around the celestial sphere CE midway between the celestial poles. SCP THE CELESTIAL SPHERE E NCP Ecliptic (E) CE It is the apparent path of the Sun around the Celestial Sphere during a year. SCP THE CELESTIAL SPHERE E NCP Equinoxes and Solstices CE March 21 – Vernal Equinox June 21 – Summer Solstice September 21 – Autumnal Equinox December 21 – Winter Solstice SCP  March 21 Vernal Equinox June 21 Summer Solstice December 21 Winter Solstice September 21 Autumnal Equinox IN THE PHILIPPINES, WHY IS JUNE “HOTTER”, AND WHY IS DECEMBER “COOLER”?  THE CELESTIAL SPHERE Equinox This is where the ecliptic, and the celestial equator intersect. Vernal Equinox is marked in Right Ascension as 0 Hours Autumnal Equinox is marked in Right Ascension as 12 Hours Tropic of Cancer or 23.4* North Manila = 14.5995° N, 120.9842° E THE CELESTIAL SPHERE Z Your point of view Cardinal Points H N M Meridian (M) Horizon (H) Ikaw to E Zenith (Z) Nadir (Na) W Bonus - Altitude (Al) - Azimuth (Az) S Na THE CELESTIAL SPHERE Z Right Ascension (RA) is the celestial equivalent of longitude. H N M RA can be expressed in degrees, but it is more common to specify it in hours, minutes, and seconds of time. For example 15 hours 45 minutes, and 23 Ikaw to E seconds Declination (DEC) is the celestial sphere's equivalent of W latitude and it is expressed in degrees, as is latitude. For DEC, + and - refer to north and south, respectively. The celestial equator is 0° DEC, and the poles S are +90° and -90° Na THE CELESTIAL SPHERE Right Ascension (RA) and Declination (DEC) Examples: Polaris - RA 2h 41m 39s, Dec. +89° 15′ 51″ Sirius (as seen today) – RA 6h 46m 39s, Dec -16”45”08.2” Aldebaran (as seen today) – RA 4h37m18.09s/+16”33”26.9” Alt-Az 15* Ecliptic 10* If north is Zero Degrees, then west is 270 degrees 5* Horizon 0* Hence, Orion’s -5* Azimuth is 270 degrees due west, and Altitude is 15 degrees above the horizon -10* Celestial -15* Equator RA-DEC 15* Ecliptic 5h If north is Zero Degrees, 10* 30* 20* 10* 0* -10* -20* then -30*west is 270 degrees 5* Horizon 4h 0* Orion lies directly on the Hence, Hence, Orion Orion’s has a -5* 3h Azimuth Right Ascension is 270 degrees of 5 Hours due west, and Celestial Equator, Declinationand of 0 degrees and it is 5 hours away from Altitude is 15 degrees above the horizon -10* the Vernal Equinox 2h Celestial Equator -15* Equator  30* THE CELESTIAL 20* SPHERE 10* At this time, the Right 9h 8h 7h 6h 5h 10h 4h Ascension of Sirius is -10* approximately 6 hours 50 mins, and its -20* Declination is -18 -30* degrees with respect to the celestial sphere -40* -50*  E NCP CE SCP WHAT IS THIS FOR? 1.Fundamentals – It provides a model for describing and locating celestial objects in the sky. 2.Familiarity with the Coordinate System – Right Ascension and Declination is essential for telescope use. Determine exact location of object 3.Observational Techniques – Zenith, Meridian, Nadir, NCP, SCP, and H, are all essential when doing your observations. WHAT IS THIS FOR? 4. Everything is Physics – Earth’s movement in space. 5. Career – Dissemination of knowledge, observational research, comet hunting, asteroid hunting, occultations, tracking low orbit space junk. PATTERNS IN THE SKY As defined by the International Astronomical Union (IAU), there are 88 recognized modern CONSTELLATIONS in the night sky. A constellation is defined by boundaries set in the celestial sphere.  PATTERNS IN THE SKY ASTERISM, a pattern of stars that is not a constellation. An asterism can be part of a constellation, such as the Big Dipper, which is in the constellation Ursa Major, and can even span across constellations, such as the Summer Triangle, which is formed by the three bright stars Deneb, Altair, and Vega. MEASURING THE SKY WITH YOUR HANDS PROMINENT PATTERNS Winter Hexagon or Winter Triangle 1. Sirius 2. Capella 3. Rigel 4. Procyon 5. Aldebaran 6. Pollux PROMINENT PATTERNS Summer Triangle 1.Altair 2.Deneb 3.Vega PROMINENT PATTERNS Ursa Major and Ursa Minor 1. Big Dipper 2. Small Dipper 3. Polaris  PROMINENT Scorpius PATTERNS Finding the Milky Way In between Scorpius and Sagittarius Prominent Stars: 1. Antares 2. Kaus Astralis Sagittarius PROMINENT PATTERNS Prominent Southern Constellations 1.Crux 2.Centaurus Introduction to Astronomy Reviewer QUIZBEE!!!!!  Mechanics Group Formation: The class will be divided into 5 teams. Answering Procedure: ► For each question, the slide will display the question first. ► A student from any team must raise their hand to answer. Only the first student to raise their hand will be called to respond. ► If the answer is correct, their team gets 1 point. ► In case of an incorrect answer, the other teams can raise their hand to answer, until the correct response is given or time runs out. Rewards ► The highest scoring team will receive 20 points added to their midterm exam. ► The second place team will get 15 points. ► Third place will get 10 points. ► Fourth place will get 5 points. ► The team with the least points will get 1 point. Celestial Sphere is an imaginary sphere with the earth at its center. Geographic North Pole or True North ►It is the northernmost point on Earth’s surface, located at 90° latitude north. Nicolas Coppernicus ► Mathematician, astronomer, and a devout catholic. ► Proposed the Sun was at the center of the Universe.  Al-Biruni ►Claimed the Earth rotated on its own axis ►Was also able to compute Earth’s circumference Tycho Brahe ► Proposed alterations to the “Heliocentric Model”, with the other planets orbiting around the Sun, while it revolved around the Earth Johannes Kepler ►German Astronomer ►Discovered three major Laws of Planetary Motion  Edwin Hubble ►is renowned for determining that there are other galaxies in the Universe beyond the Milky Way, and for observing that the universe is expanding at a constant rate. Carl Sagan ►“The universe is a pretty big place. If it's just us, seems like an awful waste of space.” True or False FALSE ►Astrology is the study of all things beyond Earth’s atmosphere FALSE ►During solstices, days are as long as nights TRUE ► According to Astronomers, the universe started with a rapid expansion of energy and sub-atomic particles, spreading in all directions. FALSE ►The Big Dipper is a group of stars known as a constellation TRUE ►The summer triangle and the winter triangle are a group of stars called asterisms FALSE ►In the celestial sphere, the sun follows the path of the equator. TRUE ►Refracting telescopes uses lens as its primary objective FALSE ►This is the light path of a compound telescope  50 a. Altair (2 points) i. R.A. = ii. Dec = 40 b. Antares (2 points) Celestial Equator i. R.A. = 30 Altair ii. Dec = c. Arcturus (2 points) 20 Arcturus i. R.A. = 19 hour 50 mins approx. i. R.A. = ii. Dec = 9 degrees approx. ii. Dec = Altair 10 Antares i. R.A. = 16 Hours 30 mins approx. ii. Dec = - 28 degrees 14h approx. 20h 19h 18h 17h 16h 15h Arcturus Ecliptic i. R.A. = 14 hours 15 mins -10 approx. ii. Dec = 19 degrees approx. -20 Antare -30 s -40 Compute for the Following: 6-Inch Reflecting Telescope on a Dobsonian Mount - 150 mm diameter - Focal Length = 610 mm Focal Ratio = F/4 - Eyepiece 25mm = 24.4x o 25mm 35mm = 17.4x o 35mm 10mm = 61x o 10mm 8-inch Schmidt-Cassegrain on a Fork mount attached to a wedge with tracking - Diameter = 203.2 mm - Focal Length = 2032 mm Focal Ratio = F/10 - Eyepiece 25mm = 81.3x o 25mm 35mm = 58.1x o 35mm 10mm = 203.2x o 10mm 5mm = 406.4 o 5mm  Compute for the Diameter of the Earth using Eratosthenes Model If 7*12** = 1/50 of a circle, then find the Circumference, and the Diameter Circumference = 40,075 km Diameter = 12,811 km