Presentation on theme: "Reach for the Stars Presented by Linder Winter"— Presentation transcript:
1Reach for the Stars Presented by Linder Winter National Event SupervisorE-S Rules Committee Chair
2Part I: Basic Event Information Reach for the StarsPart I: Basic Event Information
3DescriptionStudents will demonstrate an understand-ing and basic knowledge of the properties and evolution of sun-sized and massive stars, open clusters and globular clusters, and normal and star-forming galaxies.
4Note:“Reach for the Stars” is now solely a “stars” event and, as such, will no longer include:1. location and identification of planets on star charts, etc.2. the term “zodiac” to avoid the pseudo-science of astrology.3. or references to asterisms.
5Event ParametersThe only resource permitted is one 8.5” x 11.5” single or double-sided sheet of computer-generated or handwritten notes per team. Notes may include graphics, tables, and/or text.
6Event ParametersSuggested information to include on the resource sheet for each star:a. Name. Example. Solb. Classification. G2Vc. Evolutionary stage. Main sequenced. Constellatione. RA/Declination, i.e. locationf. Unique characteristics, if any
7Event ParametersSuggested information to include on the resource sheet for each Deep Sky Object:a. Nameb. Constellationc. Messier number, i.e. M1, M13, etc.d. Kind of object: SNR, Globular cluster, etc.e. RA/Declination (for location)f. Thumbnail imageg. Unique characteristics, if any
8The CompetitionThe event is divided into two parts. Notes may be used in both parts.
9The CompetitionPart I: Participants will be asked to identify the stars, constellations, and deep sky objects included in the lists below as they appear on star charts, H-R diagrams, portable star labs, photos, or planetariums, and be knowledgeable about the evolutionary stages of all stars and deep sky objects. (Participants must bring a flashlight with a red filter and a clipboard unless they have been informed that the event will not take place in a planetarium or a portable star lab.)
10StarsThe stars in the list were chosen to repre-sent the various stages in the lives of stars.A few of the stars and deep sky objects on the list are not visible from the northern hemisphere. Example: there are no similar features to the Magellanic Clouds in the Northern skies.
11Constellations Constellations have been included 1. for historical purposes.2. for ease of locating specific objects in the sky.3. and for those individuals who enjoy locating them and learning their accompanying tales.Coaches should emphasize that constellations are imaginary groupings of stars with historical and literary importance, but limited scientific significance.
12Stellar Classification Standard means to record the classifi-cation of a star. Example: Earth’s sun = G2V1. Letter of class – O, B, A, F, G, K, M2. Temperature number – 0 to 93. Luminosity category – Ia, Ib, II, III, IV, V, VI, VII (Not always included. It’s proper to refer to the sun as a G2 star.)
13Spectral Classification For Earth's star, Sol, a G2V star:1. Class – G2. Relatively hot – 23. Main sequence star – V
14Stellar Classification Each star class is divided into 10 sub-classes, ranging from 0 (hottest) to 9 (coolest).
15Spectral Classification Luminosity Classes are designated by Roman numerals I thru VII, in order of decreasing luminosity:Ia (most luminous supergiants)Ib (less luminous supergiants)II (luminous giants)III (normal giants)IV (subgiants)V (main sequence and dwarfs)VI (subdwarfs) (VI stars are not always included.)VII (white dwarfs) (VIII stars are not always included.)
16Spectral Classification The color of a star depends on its temperatureRed Stars are CoolerBlue Stars are HotterSpectral ClassificationClassify stars by their spectral linesSpectral differences are due mostly to temperature, not composition.Spectral Sequence (Temperature Sequence): O B A F G K M L T
17Spectral Classification The traditional mnemonics for remembering the spectral types are based on the old Harvard OBAFGKM system.Harvard (1920s):Oh Be A Fine Girl, Kiss MeBerkeley (late `60s):Oh Buy A Fine Green Kilo ManCaltech (late `70s):On Bad Afternoons Fermented Grapes Keep Mrs. Richard Nixon Smiling
18Part II: Information for Students Reach for the StarsPart II: Information for Students
19Stellar Evolution of Stars Formation in a stellar nursery … through birth … each life stage … and final product – (white dwarf, neutron star, black hole).
22Star Clusters: Definition Gravitationally-bound collection of stars that formed from the same gas cloud.
23Image: WIYN Telescope, Kitt Peak Open Clusters1. Contain a few (typically tens to thousands of) young stars2. Individual stars are easily resolvedImage: WIYN Telescope, Kitt Peak
24Open Clusters 4. Stars within open clusters eventually disperse. 3. Open clusters are collections of hot, recently formed stars found preferentially in the spiral arms of the galaxy.4. Stars within open clusters eventually disperse.Credit: AURA, NOAO, NSF
25Image: Hubble Space Telescope Globular Clusters1. Are found in the haloes of galaxies2. Contain from tens of thousands to millions of ancient stars crowded into a more or less spherical volume of space.Image: Hubble Space Telescope
26Image: Sonoita Observatories Globular Clusters3. Their central density is sufficiently high that individual stars cannot be resolved from earth-based telescopesImage: Sonoita Observatories
27Spiral Galaxies1. Disk-shaped, usually with a bulge at the center and arms spiraling outwards2. Tend to contain more middle-aged stars along with clouds of gas and dustThe spiral galaxy NGC 1309
28Image courtesy Richard Crisp Spiral GalaxiesSpiral galaxies contain large concentrations of gas and dust.The spiral arms are waves of star formation swirling around the galaxy.New stars are hot and bright. They light up the gas and dust in the arms.Image courtesy Richard Crisp
29Elliptical Galaxies1. Contain older stars and very little gas and dust2. Can be different shapes ranging from round, to flattened, elongated spheres.3.Orbits of stars within elliptical galaxies are in random directionsNOAO/AURA/NSF
30Eliptical GalaxiesElliptical galaxies contain modest amounts of cool and warm gas, though not as much as found in spiral galaxiesThere are generally not enough gases to support much star formation.The Giant Elliptical, M87
31Galactic Types & Structure Irregular galaxies1. Poorly-defined structures2. Have lots of young stars, dust and gas.3.Show evidence of extensive star formationImage courtesy of Richard Crisp.
67Constellation: Ophiuchus Star: Bernard’s StarBernard’s Star is currently the second closest star to the Sun, at 5.96 light years (if you count the 3 stars of Alpha Centauri as one star). It also has the highest known proper motion, i.e., it is moving relative to the Sun at a greater speed than any other star. In about 8,000 years, its speed and direction will make Bernard's Star the closest star to the Sun.
69Part III: Instructional Activities Reach for the StarsPart III: Instructional Activities
70Stellar Bingo: An Introductory Activity Note: This activity has been included on your Coaches Clinic CD.
71Star Clues This activity is also on the Coaches Clinic CD. Introduces students to the H-R Diagram through a challenging activity requiring students to complete a chart from clues.
72Reach for the Stars Practice Exam Note: This practice exam has been included on your Coaches Clinic CD.The exam uses a set of “Stellar Evolution” images that may be requested from the Chandra X-ray Center.
73The Game of SPACE S = Stars P = Planets A = Astronomy C = ConstellationsE = Exploration
74STELLAR JOURNEY: The Game Participants gather mass and time to apply to three stars of varying mass. The three stars are born, live their lives, and die as either white dwarfs, neutron stars, or black holes.