The Sun. Structure of Sun s Outer Layers Magnetism, Sunspots, Flares, and CMEs Solar Energy and Earth s Climate. 1 February 2018
|
|
- Marilyn Thomas
- 6 years ago
- Views:
Transcription
1 The Sun Structure of Sun s Outer Layers Magnetism, Sunspots, Flares, and CMEs Solar Energy and Earth s Climate 1 February 2018 University of Rochester
2 The Sun The structure of the Sun s outer layers: convection zone, photosphere, and corona Solar activity: magnetism, sunspots, flares, and CMEs Solar activity and Earth s climate Solar energy Reading: Ryden Ch. 14 (Atmospheres) and Ch. 15 (Interiors) Layers of the Sun (image from Hinode, NASA/JAXA). 1 February 2018 (UR) Astronomy / 1
3 The Solar convection zone The Sun s interior, being fully ionized, has γ = C P /C V = 5/3 Gas is unstable to convection if T dp P dt < γ 1 = 2 γ 5 In the Sun, this is true for 2 3 R < r < R, so it has a large outer convection layer. 1 February 2018 (UR) Astronomy / 1
4 The Solar convection zone Sunspot and solar granularity observed by Dutch Open Telescope (Rutten et al. 2017, APOD 2005). Each grain is the top of a convection cell. A 1-hour time lapse of the photosphere (van Der Voort 2016), see also here. 1 February 2018 (UR) Astronomy / 1
5 The solar dynamo & the solar cycle The Sun s radiative zone rotates like a solid body but the convection zone (CZ) rotates differentially. The differential rotation winds and amplifies a poloidal solar magnetic field, turning it into a more toroidal field (Higgins 2012). This occurs because the field is frozen into the ionized material by the Lorentz force. 1 February 2018 (UR) Astronomy / 1
6 The solar dynamo & the solar cycle Convection makes the field lines twist out of the surface and loop through the lower atmosphere, creating sunspot pairs and prominences connecting them. The twisting and winding of the field lines eventually causes the poloidal field to reappear but with the N and S poles reversed. 1 February 2018 (UR) Astronomy / 1
7 The solar dynamo & the solar cycle The reversal of the magnetic field repeats in a regular cycle. There are 22 years between identical configurations of the field. The self-generation process of the field is called dynamo action. For the Sun, there are 11 years between sunspot number maxima. From P. Charbonneu, U. Montreal (Charbonneau 2010). See also here. 1 February 2018 (UR) Astronomy / 1
8 The solar photosphere As we have noted, the spectrum of the sun closely resembles a blackbody. From the total energy flux at Earth total solar irradiance, (TSI), or solar constant f = erg s 1 cm 2 we get the Sun s luminosity L = erg s 1 Image from Mediawiki. TSI, L, and solar flux at most wavelengths vary little with time (which we will show). At very long and very short wavelengths, flares can change the Sun s brightness by huge factors. 1 February 2018 (UR) Astronomy / 1
9 The solar photosphere In detail: absorption lines are also seen in the solar spectrum. They match up with many known transitions of atoms, ions, and molecules. The solar spectrum. Nigel Sharp, using data from Bob Kurucz et al. (NOAO/NSO/Kitt Peak FTS/AURA/NSF). 1 February 2018 (UR) Astronomy / 1
10 The solar photosphere Spectral-line absorption by atoms and molecules is a hallmark of stars. Gases absorb strongly at the wavelengths of spectral lines (transitions between the quantum mechanical states) of the atoms and molecules of which they are composed. Stars are heated from inside and are cooler on the outside. Thus, to an outside observer, a star becomes opaque at a higher altitude for wavelengths of spectral lines. One sees deeper into the star at adjacent wavelengths. Because the deeper material is hotter, and hotter blackbodies are brighter, the star is brighter between the spectral lines. Hot Flux Cooler Wavelength 1 February 2018 (UR) Astronomy / 1
11 Chromosphere & corona The corona is heated by magneto-acoustic noise from the boiling top of the convection zone and by magnetic reconnection (flares). The coronal density is so low that it cannot cool efficiently, so it reaches temperatures > 10 6 K. From Chaisson and McMillan, Astronomy Today. 1 February 2018 (UR) Astronomy / 1
12 Corona during total solar eclipse Total solar eclipse, 2017, Carla Thomas, NASA. 1 February 2018 (UR) Astronomy / 1
13 Sunspots & solar activity Sunspots appear dark because they are slightly cooler than the rest of the solar surface. They are surrounded by hotter-than-average regions called faculae. Zeeman effect measurements show that they are maxima of the magnetic field. SOHO/NASA. 1 February 2018 (UR) Astronomy / 1
14 The 11-year sunspot cycle 1 February 2018 (UR) Astronomy / 1
15 Sunspots & solar activity Solar images from 29 Mar. 2001: He II at 30.4 nm Fe IX at 17.1 nm Visible light Note the X-ray bright faculae surrounding the sunspots. These regions add more to the Sun s luminosity than the spots take away. 1 February 2018 (UR) Astronomy / 1
16 Sunspots & solar activity Solar images from 29 Mar. 2001: He II at 30.4 nm Fe IX at 17.1 nm Visible light Note the X-ray bright faculae surrounding the sunspots. These regions add more to the Sun s luminosity than the spots take away. 1 February 2018 (UR) Astronomy / 1
17 Sunspots & solar activity Solar images from 29 Mar. 2001: He II at 30.4 nm Fe IX at 17.1 nm Visible light Note the X-ray bright faculae surrounding the sunspots. These regions add more to the Sun s luminosity than the spots take away. 1 February 2018 (UR) Astronomy / 1
18 Sunspots & solar activity X-ray emission from gas at T = 10 6 K in magnetic loops connecting the sunspots on the limb of the Sun (TRACE/NASA). 1 February 2018 (UR) Astronomy / 1
19 Sunspots & solar activity Flares are driven by magnetic reconnection within oppositely-opposed tubes of magnetic flux. The reconnected lines of B, strongly curved at first, straighten out quickly. The ions frozen to them impel other material outwards and inwards, like an arrow from a bow. Chen et al. (2008) 1 February 2018 (UR) Astronomy / 1
20 Sunspots & solar activity Large flares can lead to coronal mass ejection (CME) events, a.k.a. solar storms. CMEs are blasts of ions accelerated to high energy (v 0.3c) which expand into the Solar System. CMEs cause aurorae and wreak havoc on satellite and power systems on Earth. From STEREO/GSFC/NASA. 1 February 2018 (UR) Astronomy / 1
21 Notable CMEs September 1, 1859 The Carrington event. Strongest CME ever recorded. Flares visible to the naked eye; aurorae brighter than full moonlight and visible near the equator (Hawaii). Fires started in telegraph systems all over the world. August 2, 1972 Three strong CMEs in 15 hours, between the visits to the moon by Apollo 16 and 17. The astronauts would have been killed by the radiation had they been in space. November 4, 2003 Second-largest CME in history, one week after the fifth strongest in history, and a few months after the launch of the NASA Spitzer Space Telescope and two Mars Exploration Rovers (MERs) had taken these satellites outside the geomagnetic field. Damage to Spitzer s detectors: equivalent to 5 years of radiation damage in a few seconds. One MER s computer had to be rebooted 60 times before the memory repair routine finally worked. 1 February 2018 (UR) Astronomy / 1
22 Sunspots & solar activity The Sun s luminosity including flares and CMEs varies in sync with the sunspot number, currently by about 0.1% over the solar cycle. Data from Kopp et al. (2016) show irradiance data from about a dozen experiments: Irradiance in W/m 2 at top and sunspot number at bottom. Differences in irradiance are due to calibration differences between instruments. 1 February 2018 (UR) Astronomy / 1
23 The solar cycle & Earth s temperature The Earth s average equilibrium temperature can be estimated from P in = P out (1 A)f πr 2 = ɛσt 4 4πR 2 ( ) (1 1/4 ( A)f 1 A L T eq = = 4ɛσ ɛ 16πσr 2 Hence, a small change in solar luminosity L leads to a change T: T = dt L = 1 ( 1 A dl 4 ɛ = 1 ( 1 A L 4 ɛ 16πσr 2 ) 1/4 L 3/4 L 1 16πσr 2 ) 1/4 L 1 L = T L 4 L ) 1/4 1 February 2018 (UR) Astronomy / 1
24 The solar cycle & Earth s temperature The 150-year average of the global mean ocean surface temperature (GMOST) is 16.0 C = 289 K, and the ocean s heat capacity is such that it can respond to heating changes in about a month. That is why it is usually colder at the end of January than on December 21. A month is short compared to 11 years, so we expect T = K = K = C per 1 W m 2 change in TSI, or equivalently per change by 100 in annual sunspot number. 1 February 2018 (UR) Astronomy / 1
25 Sunspots and climate on multi-solar cycle scales Sunspots have been counted systematically for hundreds of years. Over that span there have been big swings in the peak sunspot number in solar cycles. There has been one extended period centered around the 17 th century called the Maunder Minimum, when sunspots were practically absent. Over that span there have also been big swings in Earth s climate. One extended period occurred during the 17 th century. Known as the Little Ice Age, the Earth s surface was dramatically colder than today. These coincidences have not gone unnoticed. 1 February 2018 (UR) Astronomy / 1
26 Annual sunspot number for the last 360 years Annual sunspot number200 Little Ice Age Maunder Minimum Historically harsh winters (novels by Hugo, Dickens,...) Year Sources: NOAA/NCEI and SIDC/SILSO. 1 February 2018 (UR) Astronomy / 1
27 Earth s global surface temperature To match up temperature with sunspots and their record of total solar irradiance, we have several ways of monitoring global mean ocean surface temperature, GMOST. We have global ocean surface temperature measurements taken with real thermometers going back to We have satellite measurements since the 1960s. We also have ways to recover oceanic temperatures over much longer time spans: Water-isotope abundance measurements in ice cores and tree rings. Tree ring width (e.g., Mann & Jones 2003). All of these techniques agree with the historical record for the last two millenia. 1 February 2018 (UR) Astronomy / 1
28 The last 1800 years of T and sunspots N. Hemisphere T 16 C Climatic optimum (Vikings settle Greenland) Little Ice Age year annual sunspot number Sources: Mann & Jones (2003), NASA/GISS, NOAA/NCEI, and SIDC/SILSO. 1 February 2018 (UR) Astronomy / 1
29 Sunspots & climate For much of the last 400 years, the temperature and peak sunspot number track with each other: eras with high (low) peak sunspot number go with eras with high (low) temperature. You might think this suggests that variation in solar activity produces variation in climate. There are at least three big problems with that suggestion: 1. Ice ages are even colder ( 8 C) than Little Ice Ages ( 0.4 C). Extrapolating you cannot get negative sunspot numbers. 2. The correlation deteriorates continuously through the past century; it vanished a few decades ago. 3. Some of the more recent temperature drops are much better explained by volcanic activity: absorption of sunlight by high-altitude ash and sulfuric acid (H 2 SO 4 ). 1 February 2018 (UR) Astronomy / 1
30 The last 1800 years of T and volcanic explosions N. Hemisphere T 16 C Taupo Ilopango Baekdu year Sources: Mann & Jones (2003), NASA/GISS, and MediaWiki. Kuwae Kolumbo Mt. Tambora volume of tephra [km 3 ] 1 February 2018 (UR) Astronomy / 1
31 T, solar cycle, & volcanic explosions, N. Hemisphere T 16 C Kolumbo year Sources: Mann & Jones (2003), NASA/GISS, and MediaWiki. Mt. Tambora Krakatoa volume of tephra [km 3 ] 1 February 2018 (UR) Astronomy / 1
32 T, solar cycle, & volcanic explosions, 1900 Present N. Hemisphere T 16 C Pinatubo year volume of tephra [km 3 ] Sources: Mann & Jones (2003), NASA/GISS, and MediaWiki. 1 February 2018 (UR) Astronomy / 1
33 Sunspots & climate Solar activity does not dominate the long-term substantial changes in global temperature, neither global warming nor cooling periods. Better explanations: Increases in atmospheric CO 2 since the start of the Industrial Revolution (1750s) almost certainly have caused the recent trend of average global warming. Large volcanic explosions in the tropics seem at least as promising an explanation of the Little Ice Age as the low solar activity during the Maunder Minimum. Volcanic explosions also appear to explain some of the more recent and confidently characterized (minor) global cooling events. 1 February 2018 (UR) Astronomy / 1
34 The last 1800 years of T & atmospheric CO 2 N. Hemisphere T 16 C year Sources: Mann & Jones (2003), NASA/GISS, Etheridge et al. (1998), and NOAA ESRL/Scripps atmospheric CO2 [ppm] 1 February 2018 (UR) Astronomy / 1
35 T & atmospheric CO 2, 1800 Present N. Hemisphere T 16 C year atmospheric CO2 [ppm] Sources: Mann & Jones (2003), NASA/GISS, Etheridge et al. (1998), and NOAA ESRL/Scripps. 1 February 2018 (UR) Astronomy / 1
36 Solar activity & climate on solar-cycle timescales What about smaller temperature changes on short timescales? Sunspot number, TSI, and temperature are also correlated on timescales shorter than the solar cycle. This results in a temperature change of 0.15 C per 1 W m 2 change in TSI over the 160-year thermometer record annual sunspot number year annual TSI [W m 2 ] Results on the 35-year TSI record yield a similar result: 0.11 C per W m 2 of TSI. Either way, it is significantly more than the solid expectation of 0.05 C calculated several minutes ago. 1 February 2018 (UR) Astronomy / 1
37 Solar activity & climate on solar-cycle timescales Source: NOAA/NCEI 1 February 2018 (UR) Astronomy / 1
38 Solar activity & climate on solar-cycle timescales 1 February 2018 (UR) Astronomy / 1
39 Solar activity & climate on solar-cycle timescales The amplification of TSI changes is puzzling; it cannot be accounted for by the current generation of climate models. It would be a worry even without global warming! The observed T in phase with the solar cycle cannot be produced without a factor of 5 to 7 more heat than the change in TSI. Climate models fail many simple tests like this. Like the climate itself, they are extremely complex and just do not yet work perfectly. The models will get better, but should you be worried? Yes. We cannot really predict the size of anthropogenic effects if we cannot correctly predict the size of temperature modulation from the tiny solar-cycle modulation. 1 February 2018 (UR) Astronomy / 1
40 A recent model disentangling contributions to global temperatures Right: natural and manmade influences on surface temperature, from Jean & Rind (2008). ENSO = El Niño Southern Oscillation. The peaks in 1983, 1997, and 2015 were very strong El Niño events. Volcanic aerosols spike and cool the global climate, but then decay. Effects by solar irradiance are cyclical and have been at the ±0.1 C level recently. The secular trend upwards is tracing steady increases in anthropogenic greenhouse gases (mostly CO 2 ). 1 February 2018 (UR) Astronomy / 1
41 Energy & the Sun A thought experiment: Hydrostatic equilibrium and ideal gas behavior ensure that the center of the Sun is very hot, and energy (in the form of light) is radiated from the center. The high opacity of the Sun to light determines the rate at which energy leaks out. As we have seen, it takes a long time for photons to diffuse from the center to the surface. This cannot go on forever without the Sun cooling down or replacing the energy that leaks away. We know that the solar system is about years old from many radioisotope measurements of meteorites, and that life has existed here for at least years. Therefore the Sun must have had close to its present luminosity for billions of years for liquid water to be present on Earth to facilitate life. 1 February 2018 (UR) Astronomy / 1
42 How long would the Sun s present heat last? The energy density at the center of the Sun is given by the energy density of the electron gas there, considered to be an ideal gas: u e = 3 2 n ekt The energy density of the radiation (light) about to leak away is u r = 4 c f = 4σT4 c We showed last time that it takes t years for a photon to leak from the center to the surface, so the heat lasts u e du e /dt u e u r /t = 3 2 n ekt c 4σT 4 t 3 8 kc ρ σm p T 3 t yr This is much less than the Sun s age so some process must be replacing the energy that leaks away. 1 February 2018 (UR) Astronomy / 1
Today in Astronomy 328
The Sun as a typical star: Central density, temperature, pressure The spectrum of the surface (atmosphere) of the Sun The structure of the sun s outer layers: convection, rotation, magnetism and sunspots
More informationThe Sun Our Star. Properties Interior Atmosphere Photosphere Chromosphere Corona Magnetism Sunspots Solar Cycles Active Sun
The Sun Our Star Properties Interior Atmosphere Photosphere Chromosphere Corona Magnetism Sunspots Solar Cycles Active Sun General Properties Not a large star, but larger than most Spectral type G2 It
More informationThe Interior Structure of the Sun
The Interior Structure of the Sun Data for one of many model calculations of the Sun center Temperature 1.57 10 7 K Pressure 2.34 10 16 N m -2 Density 1.53 10 5 kg m -3 Hydrogen 0.3397 Helium 0.6405 The
More informationGuidepost. Chapter 08 The Sun 10/12/2015. General Properties. The Photosphere. Granulation. Energy Transport in the Photosphere.
Guidepost The Sun is the source of light an warmth in our solar system, so it is a natural object to human curiosity. It is also the star most easily visible from Earth, and therefore the most studied.
More informationThe Sun ASTR /17/2014
The Sun ASTR 101 11/17/2014 1 Radius: 700,000 km (110 R ) Mass: 2.0 10 30 kg (330,000 M ) Density: 1400 kg/m 3 Rotation: Differential, about 25 days at equator, 30 days at poles. Surface temperature: 5800
More informationChapter 8 The Sun Our Star
Note that the following lectures include animations and PowerPoint effects such as fly ins and transitions that require you to be in PowerPoint's Slide Show mode (presentation mode). Chapter 8 The Sun
More information1. Solar Atmosphere Surface Features and Magnetic Fields
1. Solar Atmosphere Surface Features and Magnetic Fields Sunspots, Granulation, Filaments and Prominences, Coronal Loops 2. Solar Cycle: Observations The Sun: applying black-body radiation laws Radius
More informationThe Sun sends the Earth:
The Sun sends the Earth: Solar Radiation - peak wavelength.visible light - Travels at the speed of light..takes 8 minutes to reach Earth Solar Wind, Solar flares, and Coronal Mass Ejections of Plasma (ionized
More informationThe Sun. Basic Properties. Radius: Mass: Luminosity: Effective Temperature:
The Sun Basic Properties Radius: Mass: 5 R Sun = 6.96 km 9 R M Sun 5 30 = 1.99 kg 3.33 M ρ Sun = 1.41g cm 3 Luminosity: L Sun = 3.86 26 W Effective Temperature: L Sun 2 4 = 4πRSunσTe Te 5770 K The Sun
More informationThe Sun. Chapter 12. Properties of the Sun. Properties of the Sun. The Structure of the Sun. Properties of the Sun.
Chapter 12 The Sun, Our Star 1 With a radius 100 and a mass of 300,000 that of Earth, the Sun must expend a large amount of energy to withstand its own gravitational desire to collapse To understand this
More informationRadiation Zone. AST 100 General Astronomy: Stars & Galaxies. 5. What s inside the Sun? From the Center Outwards. Meanderings of outbound photons
AST 100 General Astronomy: Stars & Galaxies 5. What s inside the Sun? From the Center Outwards Core: Hydrogen ANNOUNCEMENTS Midterm I on Tue, Sept. 29 it will cover class material up to today (included)
More information1-4-1A. Sun Structure
Sun Structure A cross section of the Sun reveals its various layers. The Core is the hottest part of the internal sun and is the location of nuclear fusion. The heat and energy produced in the core is
More informationThe Sun. The Sun Is Just a Normal Star 11/5/2018. Phys1411 Introductory Astronomy. Topics. Star Party
Foundations of Astronomy 13e Seeds Phys1411 Introductory Astronomy Instructor: Dr. Goderya Chapter 8 The Sun Star Party This Friday November 9 weather permitting. See the flyer for updates in case of cancellations
More informationThe Sun. The Sun is a star: a shining ball of gas powered by nuclear fusion. Mass of Sun = 2 x g = 330,000 M Earth = 1 M Sun
The Sun The Sun is a star: a shining ball of gas powered by nuclear fusion. Mass of Sun = 2 x 10 33 g = 330,000 M Earth = 1 M Sun Radius of Sun = 7 x 10 5 km = 109 R Earth = 1 R Sun Luminosity of Sun =
More informationLearning Objectives. wavelengths of light do we use to see each of them? mass ejections? Which are the most violent?
Our Beacon: The Sun Learning Objectives! What are the outer layers of the Sun, in order? What wavelengths of light do we use to see each of them?! Why does limb darkening tell us the inner Sun is hotter?!
More informationAstronomy 150: Killer Skies. Lecture 18, March 1
Assignments: Astronomy 150: Killer Skies HW6 due next Friday at start of class HW5 and Computer Lab 1 due Night Observing continues next week Lecture 18, March 1 Computer Lab 1 due next Friday Guest Lecturer:
More information9-1 The Sun s energy is generated by thermonuclear reactions in its core The Sun s luminosity is the amount of energy emitted each second and is
1 9-1 The Sun s energy is generated by thermonuclear reactions in its core The Sun s luminosity is the amount of energy emitted each second and is produced by the proton-proton chain in which four hydrogen
More informationAstr 1050 Mon. March 30, 2015 This week s Topics
Astr 1050 Mon. March 30, 2015 This week s Topics Chapter 14: The Sun, Our Star Structure of the Sun Physical Properties & Stability Photosphere Opacity Spectral Line Formation Temperature Profile The Chromosphere
More informationAstronomy Ch 16 The Sun. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Name: Period: Date: Astronomy Ch 16 The Sun MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The light we see from the Sun comes from which layer?
More informationThe Quiet Sun The sun is currently being studied by several spacecraft Ulysses, SOHO, STEREO, and ACE.
The Quiet Sun The sun is currently being studied by several spacecraft Ulysses, SOHO, STEREO, and ACE. Messenger also contains instruments that can do some solar studies. http://www.stereo.gsfc.nasa.gov
More informationAstronomy Chapter 12 Review
Astronomy Chapter 12 Review Approximately how massive is the Sun as compared to the Earth? A. 100 times B. 300 times C. 3000 times D. 300,000 times E. One million times Approximately how massive is the
More information10/17/ A Closer Look at the Sun. Chapter 11: Our Star. Why does the Sun shine? Lecture Outline
Lecture Outline 11.1 A Closer Look at the Sun Chapter 11: Our Star Our goals for learning: Why does the Sun shine? What is the Sun's structure? Why does the Sun shine? Is it on FIRE? Is it on FIRE? Chemical
More informationOn 1 September 1859, a small white light flare erupted on the Solar surface
The Sun Our Star On 1 September 1859, a small white light flare erupted on the Solar surface 17 hours later Magnetometers recorded a large disturbance Aurorae were seen in the Carribean, Telegraphs went
More information10/18/ A Closer Look at the Sun. Chapter 11: Our Star. Why does the Sun shine? Lecture Outline
10/18/17 Lecture Outline 11.1 A Closer Look at the Sun Chapter 11: Our Star Our goals for learning: Why does the Sun shine? What is the Sun's structure? Why does the Sun shine? Is it on FIRE? Is it on
More informationAnnouncements. - Homework #5 due today - Review on Monday 3:30 4:15pm in RH103 - Test #2 next Tuesday, Oct 11
Announcements - Homework #5 due today - Review on Monday 3:30 4:15pm in RH103 - Test #2 next Tuesday, Oct 11 Review for Test #2 Oct 11 Topics: The Solar System and its Formation The Earth and our Moon
More informationPhys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 8
Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 8 MULTIPLE CHOICE 1. Granulation is caused by a. sunspots. * b. rising gas below the photosphere. c. shock waves in the corona. d. the
More informationAstronomy 1 Fall Reminder: When/where does your observing session meet? [See from your TA.]
Astronomy 1 Fall 2016 Reminder: When/where does your observing session meet? [See email from your TA.] Lecture 9, October 25, 2016 Previously on Astro-1 What is the Moon made of? How did the Moon form?
More informationWeight of upper layers compresses lower layers
Weight of upper layers compresses lower layers Gravitational equilibrium: Energy provided by fusion maintains the pressure Gravitational contraction: Provided energy that heated core as Sun was forming
More informationThe Project. National Schools Observatory
Sunspots The Project This project is devised to give students a good understanding of the structure and magnetic field of the Sun and how this effects solar activity. Students will work with sunspot data
More informationOur Star: The Sun. Layers that make up the Sun. Understand the Solar cycle. Understand the process by which energy is generated by the Sun.
Goals: Our Star: The Sun Layers that make up the Sun. Understand the Solar cycle. Understand the process by which energy is generated by the Sun. Components of the Sun Solar Interior: Core: where energy
More informationThe Sun: Our Star. The Sun is an ordinary star and shines the same way other stars do.
The Sun: Our Star The Sun is an ordinary star and shines the same way other stars do. Announcements q Homework # 4 is due today! q Units 49 and 51 Assigned Reading Today s Goals q Today we start section
More informationAn Overview of the Details
Guiding Questions The Sun Our Extraordinary Ordinary Star 1. What is the source of the Sun s energy? 2. What is the internal structure of the Sun? 3. How can astronomers measure the properties of the Sun
More informationHow the Sun Works. Presented by the
How the Sun Works Presented by the The Sun warms our planet every day, provides the light by which we see and is absolutely necessary for life on Earth. In this presentation, we will examine the fascinating
More informationThe Sun as Our Star. Properties of the Sun. Solar Composition. Last class we talked about how the Sun compares to other stars in the sky
The Sun as Our Star Last class we talked about how the Sun compares to other stars in the sky Today's lecture will concentrate on the different layers of the Sun's interior and its atmosphere We will also
More informationLecture 17 The Sun October 31, 2018
Lecture 17 The Sun October 31, 2018 1 2 Exam 2 Information Bring a #2 pencil! Bring a calculator. No cell phones or tablets allowed! Contents: Free response problems (2 questions, 10 points) True/False
More informationStudent Instruction Sheet: Unit 4 Lesson 3. Sun
Student Instruction Sheet: Unit 4 Lesson 3 Suggested time: 1.25 Hours What s important in this lesson: Sun demonstrate an understanding of the structure, and nature of our solar system investigate the
More informationCorrection to Homework
Today: Chapter 10 Reading Next Week: Homework Due March 12 Midterm Exam: March 19 Correction to Homework #1: Diameter of eye: 2.5 cm #10: See Ch. 11 Office Hours Monday. 11AM -2 PM Help Sessions Available:
More informationThe Sun Our Extraordinary Ordinary Star
The Sun Our Extraordinary Ordinary Star 1 Guiding Questions 1. What is the source of the Sun s energy? 2. What is the internal structure of the Sun? 3. How can astronomers measure the properties of the
More informationAn Overview of the Details
The Sun Our Extraordinary Ordinary Star 1 Guiding Questions 1. What is the source of the Sun s energy? 2. What is the internal structure of the Sun? 3. How can astronomers measure the properties of the
More informationThe Structure of the Sun. CESAR s Booklet
How stars work In order to have a stable star, the energy it emits must be the same as it can produce. There must be an equilibrium. The main source of energy of a star it is nuclear fusion, especially
More informationLesson 3 THE SOLAR SYSTEM
Lesson 3 THE SOLAR SYSTEM THE NATURE OF THE SUN At the center of our solar system is the Sun which is a typical medium sized star. Composed mainly of Hydrogen (73% by mass), 23% helium and the rest is
More informationB B E D B E D A C A D D C
B B A C E E E E C E D E B B A D B E E A E E B C C A B B E D B E D A C A D D C E D Assigned Reading Read Chapters 8.1 and 8.2 Colonel Cady Coleman, Astronaut: Lessons from Space Lead Straight Back to Earth,
More informationChapter 14 Our Star Pearson Education, Inc.
Chapter 14 Our Star Basic Types of Energy Kinetic (motion) Radiative (light) Potential (stored) Energy can change type, but cannot be created or destroyed. Thermal Energy: the collective kinetic energy
More informationThe Sun: A Star of Our Own ASTR 2110 Sarazin
The Sun: A Star of Our Own ASTR 2110 Sarazin Sarazin Travel Wednesday, September 19 afternoon Friday, September 21 Will miss class Friday, September 21 TA Molly Finn will be guest lecturer Cancel Office
More informationNext quiz: Monday, October 24
No homework for Wednesday Read Chapter 8! Next quiz: Monday, October 24 1 Chapter 7 Atoms and Starlight Types of Spectra: Pictorial Some light sources are comprised of all colors (white light). Other light
More informationChapter 14 Lecture. The Cosmic Perspective Seventh Edition. Our Star Pearson Education, Inc.
Chapter 14 Lecture The Cosmic Perspective Seventh Edition Our Star 14.1 A Closer Look at the Sun Our goals for learning: Why does the Sun shine? What is the Sun's structure? Why does the Sun shine? Is
More informationAstronomy 210. Outline. Nuclear Reactions in the Sun. Neutrinos. Solar Observing due April 15 th HW 8 due on Friday.
Astronomy 210 Outline This Class (Lecture 30): Solar Neutrinos Next Class: Stars: Physical Properties Solar Observing due April 15 th HW 8 due on Friday. The Sun Our closest star The Outer Layers of the
More informationName: Date: 2. The temperature of the Sun's photosphere is A) close to 1 million K. B) about 10,000 K. C) 5800 K. D) 4300 K.
Name: Date: 1. What is the Sun's photosphere? A) envelope of convective mass motion in the outer interior of the Sun B) lowest layer of the Sun's atmosphere C) middle layer of the Sun's atmosphere D) upper
More informationThe Sun is the nearest star to Earth, and provides the energy that makes life possible.
1 Chapter 8: The Sun The Sun is the nearest star to Earth, and provides the energy that makes life possible. PRIMARY SOURCE OF INFORMATION about the nature of the Universe NEVER look at the Sun directly!!
More informationChapter 14 Lecture. Chapter 14: Our Star Pearson Education, Inc.
Chapter 14 Lecture Chapter 14: Our Star 14.1 A Closer Look at the Sun Our goals for learning: Why does the Sun shine? What is the Sun's structure? Why does the Sun shine? Is it on FIRE? Is it on FIRE?
More informationStars and Galaxies. The Sun and Other Stars
CHAPTER 22 Stars and Galaxies LESSON 2 The Sun and Other Stars What do you think? Read the two statements below and decide whether you agree or disagree with them. Place an A in the Before column if you
More informationASTRONOMY. Chapter 15 THE SUN: A GARDEN-VARIETY STAR PowerPoint Image Slideshow
ASTRONOMY Chapter 15 THE SUN: A GARDEN-VARIETY STAR PowerPoint Image Slideshow FIGURE 15.1 Our Star. The Sun our local star is quite average in many ways. However, that does not stop it from being a fascinating
More informationThe Sun. The Chromosphere of the Sun. The Surface of the Sun
Key Concepts: Lecture 22: The Sun Basic properties of the Sun The outer layers of the Sun: Chromosphere, Corona Sun spots and solar activity: impact on the Earth Nuclear Fusion: the source of the Sun s
More informationChapter 14 Our Star A Closer Look at the Sun. Why was the Sun s energy source a major mystery?
Chapter 14 Our Star 14.1 A Closer Look at the Sun Our goals for learning Why was the Sun s energy source a major mystery? Why does the Sun shine? What is the Sun s structure? Why was the Sun s energy source
More informationOur sole source of light and heat in the solar system. A very common star: a glowing g ball of gas held together by its own gravity and powered
The Sun Visible Image of the Sun Our sole source of light and heat in the solar system A very common star: a glowing g ball of gas held together by its own gravity and powered by nuclear fusion at its
More informationMeteorites. A Variety of Meteorite Types. Ages and Compositions of Meteorites. Meteorite Classification
Meteorites A meteor that survives its fall through the atmosphere is called a meteorite Hundreds fall on the Earth every year Meteorites do not come from comets First documented case in modern times was
More informationThe Magnetic Sun. CESAR s Booklet
The Magnetic Sun CESAR s Booklet 1 Introduction to planetary magnetospheres and the interplanetary medium Most of the planets in our Solar system are enclosed by huge magnetic structures, named magnetospheres
More informationXV. Understanding recent climate variability
XV. Understanding recent climate variability review temperature from thermometers, satellites, glacier lengths and boreholes all show significant warming in the 2th C+ reconstruction of past temperatures
More informationA Closer Look at the Sun
Our Star A Closer Look at the Sun Our goals for learning Why was the Sun s energy source a major mystery? Why does the Sun shine? What is the Sun s structure? Why was the Sun s energy source a major mystery?
More informationChapter 9 The Sun. Nuclear fusion: Combining of light nuclei into heavier ones Example: In the Sun is conversion of H into He
Our sole source of light and heat in the solar system A common star: a glowing ball of plasma held together by its own gravity and powered by nuclear fusion at its center. Nuclear fusion: Combining of
More informationThe Sun. Nearest Star Contains most of the mass of the solar system Source of heat and illumination
The Sun Nearest Star Contains most of the mass of the solar system Source of heat and illumination Outline Properties Structure Solar Cycle Energetics Equation of Stellar Structure TBC Properties of Sun
More informationPrentice Hall EARTH SCIENCE
Prentice Hall EARTH SCIENCE Tarbuck Lutgens Chapter 24 Studying the Sun 24.1 The Study of Light Electromagnetic Radiation Electromagnetic radiation includes gamma rays, X-rays, ultraviolet light, visible
More informationModule 4: Astronomy - The Solar System Topic 2 Content: Solar Activity Presentation Notes
The Sun, the largest body in the Solar System, is a giant ball of gas held together by gravity. The Sun is constantly undergoing the nuclear process of fusion and creating a tremendous amount of light
More informationChapter 10 Our Star. X-ray. visible
Chapter 10 Our Star X-ray visible Radius: 6.9 10 8 m (109 times Earth) Mass: 2 10 30 kg (300,000 Earths) Luminosity: 3.8 10 26 watts (more than our entire world uses in 1 year!) Why does the Sun shine?
More information8.2 The Sun pg Stars emit electromagnetic radiation, which travels at the speed of light.
8.2 The Sun pg. 309 Key Concepts: 1. Careful observation of the night sky can offer clues about the motion of celestial objects. 2. Celestial objects in the Solar System have unique properties. 3. Some
More informationIX. Dwarf Planets A. A planet is defined to be an object that is large enough to coalesce into a sphere and to have cleared its orbit of other
7/1 VII. VIII. Uranus A. Gas Giant 1. Rings but not visible 2. HUGE axial tilt 97! 3. Mostly hydrogen and helium 4. Medium rotation rate 5. Cold 55 K at the cloud tops B. Physical characteristics 1. Mass:
More informationThe General Properties of the Sun
Notes: The General Properties of the Sun The sun is an average star with average brightness. It only looks bright because it s so close. It contains 99% of the mass of the solar system. It is made of entirely
More informationOutline. Astronomy: The Big Picture. Earth Sun comparison. Nighttime observing is over, but a makeup observing session may be scheduled. Stay tuned.
Nighttime observing is over, but a makeup observing session may be scheduled. Stay tuned. Next homework due Oct 24 th. I will not be here on Wednesday, but Paul Ricker will present the lecture! My Tuesday
More informationHydrogen Lines. What can we learn from light? Spectral Classification. Visible Hydrogen Spectrum Lines: Series. Actual Spectrum from SDSS
What can we learn from light? Hydrogen Lines Temperature Energy Chemical Composition Speed towards or away from us All from the! Lower E, Lower f, λ Visible! Higher E, Higher f, λ Visible Hydrogen Spectrum
More informationSolar Dynamics Affecting Skywave Communications
Solar Dynamics Affecting Skywave Communications Ken Larson KJ6RZ October 2010 1 Page Subject 3 1.0 Introduction 3 2.0 Structure of the Sun 3 2.1 Core 3 2.2 Radiation Zone 4 2.3 Convection Zone 4 2.4 Photosphere
More informationStars. The size of the Sun
Stars Huge spheres of gas floating in space Composed primarily of H, He. Produce their own energy. Our Galaxy: 10 11 (100 billion) stars. The Sun: a typical star Stars range from ~ 0.1 to ~ 20 M M = solar
More informationConvection causes granules. Photosphere isn t actually smooth! Granules Up-Close: like boiling water. Corona or of the Sun. Chromosphere: sphere of
Overview Properties of the Sun Sun s outer layers Photosphere Chromosphere Corona Solar Activity Sunspots & the sunspot cycle Flares, prominences, CMEs, aurora Sun s Interior The Sun as an energy source
More informationOur sun is the star in our solar system, which lies within a galaxy (Milky Way) within the universe. A star is a large glowing ball of gas that
Our sun is the star in our solar system, which lies within a galaxy (Milky Way) within the universe. A star is a large glowing ball of gas that generates energy through nuclear fusion in its core. The
More informationThe Sun. the main show in the solar system. 99.8% of the mass % of the energy. Homework due next time - will count best 5 of 6
The Sun the main show in the solar system 99.8% of the mass 99.9999...% of the energy 2007 Pearson Education Inc., publishing as Pearson Addison-Wesley Homework due next time - will count best 5 of 6 The
More information2. Terrestrial Planet G 9. Coulomb Force C 16. Babcock model Q. 3. Continuous Spectrum K 10. Large-impact hypothesis I 17.
Astronomy 1 S 16 Exam 1 Name Identify terms Label each term with the appropriate letter of a definition listed 1. Spectral line R 8. Albedo H 15. helioseismology E 2. Terrestrial Planet G 9. Coulomb Force
More informationThe Sun: Our Star. A glowing ball of gas held together by its own gravity and powered by nuclear fusion
Our Star, the Sun The Sun: Our Star A glowing ball of gas held together by its own gravity and powered by nuclear fusion Radius: 700,000 km (435,000 miles) Diameter: 1.392 million km (865,000 miles) Circumference:
More informationPTYS/ASTR 206. The Sun 3/1/07
The Announcements Reading Assignment Review and finish reading Chapter 18 Optional reading March 2006 Scientific American: article by Gene Parker titled Shielding Space Travelers http://en.wikipedia.org/wiki/solar_variability
More informationShort-Term Climate Variability (Ch.15) Volcanos and Climate Other Causes of Holocene Climate Change
Short-Term Climate Variability (Ch.15) Volcanos and Climate Other Causes of Holocene Climate Change Volcanos and Climate We learned in Chapter 12 that the volanos play an important role in Earth s climate
More informationThe Sun. 1a. The Photosphere. A. The Solar Atmosphere. 1b. Limb Darkening. A. Solar Atmosphere. B. Phenomena (Sunspots) C.
The Sun 1 The Sun A. Solar Atmosphere 2 B. Phenomena (Sunspots) Dr. Bill Pezzaglia C. Interior Updated 2014Feb08 A. The Solar Atmosphere 1. Photosphere 2. Chromosphere 3. Corona 4. Solar Wind & earthly
More informationChap 14: The Sun A Typical Star Here s the Story I ll Unfold for you
Chap 14: The Sun A Typical Star Here s the Story I ll Unfold for you What s it made of? A star: self-supporting partially ionized gas balancing gravity w/ pressure Nuclear fusion and how it powers the
More informationAstronomy 404 October 18, 2013
Astronomy 404 October 18, 2013 Parker Wind Model Assumes an isothermal corona, simplified HSE Why does this model fail? Dynamic mass flow of particles from the corona, the system is not closed Re-write
More informationAstronomy 1 Winter 2011
Astronomy 1 Winter 2011 Lecture 19; February 23 2011 Asteroids Comets Meteors Previously on Astro-1 Homework Due 03/02/11 On your own: answer all the review questions in chapters 16 17 and 18 To TAs: answer
More informationTypes of Stars 1/31/14 O B A F G K M. 8-6 Luminosity. 8-7 Stellar Temperatures
Astronomy 113 Dr. Joseph E. Pesce, Ph.D. The Nature of Stars For nearby stars - measure distances with parallax 1 AU d p 8-2 Parallax A January ³ d = 1/p (arcsec) [pc] ³ 1pc when p=1arcsec; 1pc=206,265AU=3
More informationThe Sun. 1a. The Photosphere. A. The Solar Atmosphere. 1b. Limb Darkening. A. Solar Atmosphere. B. Phenomena (Sunspots) C.
The Sun 1 The Sun A. Solar Atmosphere 2 B. Phenomena (Sunspots) Dr. Bill Pezzaglia C. Interior Updated 2006Sep18 A. The Solar Atmosphere 1. Photosphere 2. Chromosphere 3. Corona 4. Solar Wind 3 1a. The
More informationSunspot Cycle Worksheet
Sunspot Cycle Worksheet Read the Explore information and answer the Explain questions in your own words. Explore: Global warming and climate change are international concerns and the focus of much controversy.
More informationLecture 14: Solar Cycle. Observations of the Solar Cycle. Babcock-Leighton Model. Outline
Lecture 14: Solar Cycle Outline 1 Observations of the Solar Cycle 2 Babcock-Leighton Model Observations of the Solar Cycle Sunspot Number 11-year (average) cycle period as short as 8 years as long as 15
More informationEarth/Space/Physics Kristy Halteman.
Earth/Space/Physics Kristy Halteman http://www.lesia.obspm.fr/~bonnin/fichiers/images/sun-soho011905-1919z.jpg A. Properties 1. 330,000 times more massive than the Earth. http://www.37signals.com/svn/images/sun_v_planets.jpg
More informationHas the Sun lost its spots?
Has the Sun lost its spots? M. S. Wheatland School of Physics Sydney Institute for Astrophysics University of Sydney Research Bite 3 September 2009 SID ERE MENS E A DEM MUT ATO The University of Sydney
More informationThe Sun. How are these quantities measured? Properties of the Sun. Chapter 14
The Sun Chapter 14 The Role of the Sun in the Solar System > 99.9% of the mass Its mass is responsible for the orderly orbits of the planets Its heat is responsible for warming the planets It is the source
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Clouds Meteorology Photochemistry Atmospheric Escape EAS 4803/8803 - CP 11:1 Structure Generalized Hydrostatic Equilibrium P( z) = P( 0)e z # ( ) " dr / H r
More informationAy 1 Lecture 8. Stellar Structure and the Sun
Ay 1 Lecture 8 Stellar Structure and the Sun 8.1 Stellar Structure Basics How Stars Work Hydrostatic Equilibrium: gas and radiation pressure balance the gravity Thermal Equilibrium: Energy generated =
More informationLogistics 2/14/17. Topics for Today and Thur. Helioseismology: Millions of sound waves available to probe solar interior. ASTR 1040: Stars & Galaxies
ASTR 1040: Stars & Galaxies Pleiades Star Cluster Prof. Juri Toomre TAs: Piyush Agrawal, Connor Bice Lecture 9 Tues 14 Feb 2017 zeus.colorado.edu/astr1040-toomre Topics for Today and Thur Helioseismology:
More informationChapter 24: Studying the Sun. 24.3: The Sun Textbook pages
Chapter 24: Studying the Sun 24.3: The Sun Textbook pages 684-690 The sun is one of the 100 billion stars of the Milky Way galaxy. The sun has no characteristics to make it unique to the universe. It is
More informationAstronomy Exam 3 - Sun and Stars
Astronomy Exam 3 - Sun and Stars Study online at quizlet.com/_4zgp6 1. `what are the smallest group of stars in the H-R diagram 2. A star has a parallax of 0.05". what is the distance from the earth? white
More informationSolar Activity The Solar Wind
Solar Activity The Solar Wind The solar wind is a flow of particles away from the Sun. They pass Earth at speeds from 400 to 500 km/s. This wind sometimes gusts up to 1000 km/s. Leaves Sun at highest speeds
More informationCHAPTER 29: STARS BELL RINGER:
CHAPTER 29: STARS BELL RINGER: Where does the energy of the Sun come from? Compare the size of the Sun to the size of Earth. 1 CHAPTER 29.1: THE SUN What are the properties of the Sun? What are the layers
More informationStars, Galaxies & the Universe Announcements. Stars, Galaxies & the Universe Observing Highlights. Stars, Galaxies & the Universe Lecture Outline
Stars, Galaxies & the Universe Announcements Lab Observing Trip Next week: Tues (9/28) & Thurs (9/30) let me know ASAP if you have an official conflict (class, work) - website: http://astro.physics.uiowa.edu/~clang/sgu_fall10/observing_trip.html
More informationSun s Properties. Overview: The Sun. Composition of the Sun. Sun s Properties. The outer layers. Photosphere: Surface. Nearest.
Overview: The Sun Properties of the Sun Sun s outer layers Photosphere Chromosphere Corona Solar Activity Sunspots & the sunspot cycle Flares, prominences, CMEs, aurora Sun s Interior The Sun as an energy
More informationHelios in Greek and Sol in Roman
Helios in Greek and Sol in Roman Drove his chariot across the sky to provide daylight Returned each night in a huge golden cup on the river Oceanus His son Phaeton drove the chariot one day but lost control
More informationAstronomy 114. Lecture 13: Energy generation, magnetic fields. Martin D. Weinberg. UMass/Astronomy Department
Astronomy 114 Lecture 13: Energy generation, magnetic fields Martin D. Weinberg weinberg@astro.umass.edu UMass/Astronomy Department A114: Lecture 13 05 Mar 2007 Read: Ch. 19 Astronomy 114 1/17 Announcements
More information