1 AFG Observations of the Sun Pål Brekke Norwegian Space Centre/UNIS
2 Types of telescopes Refractor - light passes through a primary lense and a eyepiece lens Reflector - light is reflected and focussed by a primary and secondary mirrors, thus can be built more compact. 2
3 History of Solar Observatories Huygens 123-foot-long refractor Hevelius 150-foot-long refractor
4 History of Solar Observatories Harvard 15-inch refractor Naval Observatory 26 inch refractor
5 History of Solar Observatories Yerkes 40-inch refractor Newtons reflector
6 History of Solar Observatories Herchel 20-foot-long refractor Hooker 100-inch reflector
7 History of Solar Observatories Herchel 200-inch refractor Pål Brekke, Norwegian Space Centre/UNIS
8 History of Solar Observatories Reber s Radio telescope
9 History of Solar Observatories Very Large Array Radio telescope
10 Pål Brekke, Norwegian Space Centre/UNIS Kitt Peak National Observatory, USA
11 Turbulence in the atmosphere limits the performance of astronomical Telescopes! Turbulence is the reason why stars twinkle! More important for astronomy, turbulence spreads out the light from a star; makes it a blob rather than a point Even the largest ground-based astronomical telescopes have no better resolution than an 8" backyard telescope!
12 How to correct for atmospheric blurring Measure details of blurring from guide star near the object you want to observe Calculate (on a computer) the shape to apply to deformable mirror to correct blurring Light from both guide star and astronomical object is reflected from deformable mirror; distortions are removed
13 Schema4c of adap4ve op4cs system
14 Neptune at 1.65 microns Without adaptive optics With Keck adaptive optics 2.3 arc sec May 24, 1999 June 27, 1999
15 URANUS at 1.65 microns
16 Tenerife Without corrections With corrections Pål Brekke, Norwegian Space Centre/UNIS
17 Observatories on top of vulcanoes
18 Pål Brekke, Norwegian Space Centre/UNIS World best telescope Sharpest ever pictures of the Sun Swedish Vacuum Telescope at LaPalma Can resolve features 35 km on the solar surface
19 Close-up of sunspots Sunspots Sharpest ever pictures of the Sun SWT LaPalma
20 Venus Transit from LaPalma
21 Solar and spectrum
22 Electromagnetic radiation 22
23 The Sun from Space
24 Exploring the Sun at different wavelengths ç Different views of a biking kid Different views of the Sun è Pål Brekke, Norwegian Space Centre/UNIS
25 Spectrum is like fingerprints of a star Spectrum is like fingerprints of a star. It provides information about the physical properties of the star: composition, abundance, temperature, density and line-of-sight motions, etc. Once we have these information, we can develop models and theories to understand how a star works. SOHO/UVCS Observations of the corona above an active region
26 What can we learn from a spectrum #1: Line Intensity Less particles lower intensity (fainter line) More particles higher intensity (brighter line)
27 What can we learn from a spectrum #2: Line Profile Slower random motion à narrower width Faster random motion à wider width
28 What can we learn from a spectrum #3: Line ShiM Source moving toward us à blue shift (shorter wavelength) Source moving away from us à red shift (longer wavelength)
30 First Glimpse of the Sun from Space After World War II, captured V2 rockets provided a means for sending scientific instruments above the bulk of the earth's atmosphere, which absorbed ultraviolet (UV) radiation. To study the nature of that absorption, and to examine the ultraviolet portion of the solar spectrum, a group at the Naval Research Laboratory (NRL) in Washington D.C. led by physicist Richard Tousey designed a rugged solar spectrograph to fly in the V2 warhead. 12 spectrometers were built The first spectrograph was placed in the warhead of the missile for a flight in June 1946 and confirmed that recovery was going to be a major problem. The spectrographs were then placed in the tail fins, and explosive bolts were added break the vehicle into two pieces on descent, destroying is aerodynamic form. The first successful flight of the NRL UV spectrograph was on October 10, The missile reached an altitude of 173 km and the series of spectra obtained during ascent showed the decrease in UV absorption with altitude and helped set the upper limit to the Earth's ozone layer.
31 First UV spectrum of the Sun
32 Sounding rockets s4ll useful for Solar Observa4ons
33 High Resolu4on Telescope and Spectrograph Since its first flight in 1975, the NRL High Resolu4on Telescope and Spectrograph (HRTS) has now recorded high quality ultraviolet spectra of the sun on 8 rocket flights and during extended opera4ons on the Space ShuTle Spacelab 2 mission in 1985.
34 Previous Solar Space Missions OSO 1-8 ( ) Skylab SO54 Skylab ATM ( ) Coronal holes Coronal loops Spectral atlas Dynamics of the TR Helios 1 & 2 ( ) Plasma & par4cles down to 0.3 AU SMM ( ) Solar irradiance (ACRIM) Flares (Hard and Soa X- ray) CME s UV spectral atlas, dynamics Hinotori ( ) Coronas- I ( ) Yohkoh ( ) Ulysses ( )
35 The OSO Satellites The Orbi4ng Solar Observatories were the earliest set of satellites designed to study the Sun. They arose from even earlier sounding rockets flights that showed the importance of gefng above the Earth's atmosphere to observe the Sun.
36 First observations of a coronal mass ejection The total solar eclipse of 18 July 1860 was probably the most thoroughly observed eclipse up to that time. Modern Solar Observatories
37 Skylab Apollo Telescope Mount Skylab, the first US space sta4on, was launched into orbit on May 14, 1973 as part of the Apollo program. This 91 metric ton structure was 36 meters (four stories) high, 6.7 meters in diameter and flew at an al4tude of 435 km (270 miles). When Skylab was launched it lost a solar panel and part of its external shielding. Skylab astronauts had to rig a "golden umbrella" to keep their habitat comfortable. Skylab re- entered the Earth's atmosphere in 1979 over Australia. This re- entry was a year or two earlier than expected.
38 Skylab Apollo Telescope Mount Skylab included eight separate solar experiments on its Apollo Telescope Mount: two X- ray telescopes (an X- ray and extreme ultraviolet camera); an ultraviolet spectroheliometer; an extreme ultraviolet spectroheliograph and an ultraviolet spectroheliograph; a white light coronagraph; and two hydrogen- alpha telescopes
39 The Solar Maximum Mission The Solar Maximum Mission (SMM or SolarMax) was launched on February 14, It carried several scien4fic instruments which provided new insights into the nature of solar flares. The spacecraa was rescued and repaired by a 1984 Space ShuTle Challenger mission. This rescue and repair of SMM, extended the useful life4me of the mission to allow for beter coverage of the solar ac4vity cycle. Replaced both the spacecraa Aftude Control System and the coronagraph's Main Electronics Box. SMM reentered the Earth's atmosphere and burned- up on December 2, 1989.
40 Spacelab 2 Spacelab 2, launched on the Space ShuTle Challenger on July 29, 1985, carried several solar instruments including the Solar Op4cal Universal Polarimeter (SOUP), the Coronal Helium Abundance Spacelab Experiment (CHASE), the High Resolu4on Telescope and Spectrograph (HRTS), and the Solar Ultraviolet Spectral Irradiance Monitor (SUSIM). The HRTS experiment studied features in the chromosphere, corona, and transi4on region using a telescope and spectrograph to observe emissions in the ultraviolet region of the solar spectrum.
41 Yohkoh The Yohkoh Mission is a Japanese Solar mission with US and UK collaborators. It was launched into Earth orbit in August of 1991 and con4nues to provide valuable data about the Sun's corona and solar flares. The satellite carries four instruments - a Soa X- ray Telescope (SXT), a Hard X- ray Telescope (HXT), a Bragg Crystal Spectrometer (BCS), and a Wide Band Spectrometer (WBS). Yohkoh recently (December 2001) suffered a spacecraa failure that has put this mission on hold. During the solar eclipse of December 14th the spacecraa lost poin4ng and the bateries discharged. The spacecraa operators have been unable to command the satelite to point toward the sun.
42 Ulysses The Ulysses Mission was originally proposed as a dual spacecraa mission to simultaneously explore the regions over the Sun's north and south poles. Funding problems reduced the mission to a single spacecraa set for launch in The Challenger disaster then pushed the actual launch by four years. The Ulysses spacecraa was launched from the Space ShuTle Discovery on October 6, 1990 on its mission over the Sun's south and north poles. This ESA/NASA mission is designed to sample the solar wind and the heliosphere at la4tudes unexplored by any other spacecraa. The Ulysses spacecraa carried a suite of instruments out to Jupiter where that planet's gravity pulled the spacecraa into a trajectory that carried it over the Sun's south pole in the fall of 1994 and its north pole in the summer of 1995
45 Ongoing Missions SOHO ( ) ACE ( ) TRACE ( ) GENESIS ( ) CORONAS- F ( ) RHESSI ( ) STEREO ( ) HINODE (2006- ) SDO ( ) IRIS (2013- )
46 The SOHO Mission Joint program between the European Space Agency (ESA) and NASA. An industry team led by Matra Marconi Space built SOHO in Europe. It s instruments were provided by nine European and three U.S. Principle Inves4gators ESA: responsible for SOHO s procurement, integra4on, and tes4ng NASA: provided launch and mission opera4ons (at Goddard Space Flight Center) Launch 2 December 1995
47 Mission Operation at NASA Goddard Space Flight Centre SOHO
48 The SOHO Mission Special orbit around Lagrangian point no 1: SOHO will follow the Earths rotation and always see the Sun Solar Interior: What are its structure and dynamics? Corona: Why does it exist and how is it heated? Solar Wind: Where is it accelerated and how? Pål Brekke, Norwegian Space Centre/UNIS
49 The en4re Sun is vibra4ng due to sound waves propaga4ng inside. The sound waves are refelcted off the surface - casuing the surface to oscillate up and down. By observing the escilla4ons, and thus the sound waves we can obtain informa4on about the solar interior (temperature, density and flow veloci4es). Helioseismology Pål Brekke, Norwegian Space Centre/UNIS
50 Helioseismology New technique which is primarily developing with SOHO/MDI data First ever images of flows in the convection zone of a star First images of the subsurface structure of sunspots Can give us the first insight into how sunspots are formed
51 We can «see» below sunspots For the first time one could study the layers below sunspots How do they form and what sustain them, Zhao et al.: 2001, ApJ 557, 384
52 SOHO «see» through the Sun Using helioseismology we can even «see» the far side of the Sun. Strong magnetic fields cause the sound waves to move slower. Far side Pål Brekke, Norwegian Space Centre/UNIS
53 Why Spectroscopy? From studying the position, shape and intensity of spectral lines we can derive physical properties of the emitting gas like: Temperature Density Flow velocities
54 Why Spectroscopy? From studying the position, shape and intensity of spectral lines we can derive physical properties of the emitting gas like: Temperature Density Flow velocities
55 Comets SOHO's Current Discovery Count is 2,378 Comets!! 55
56 Comet ISON SOHO Comet 3000 contest: 56
58 STEREO 58
60 HINODE 60
61 Microscopic observation by SOT (size of Earth) 50000km 430nm wavelength band (G-band) Solar Optical Telescope (SOT) on Hinode is the largest solar telescope flown in space, which provides the best spatial resolution. Its microscopic observation allows to observe fine structures in a Sun spot.
62 Close-up of granules 16000km 4000km 0.2 arcsec Granules and bright points corresponding to tiny magnetic features are clearly seen in the movie. Obtained data proves that SOT achieves the diffraction limit resolution of 50cm-aperture telescope, 0.2 arcsec in the wavelength of 430 nm.
63 Solar Dynamics Observatory
64 Solar Dynamics Observatory
65 The Sun observed with differet filters Photosphere Lower Chromosphere Upper Chromosphere Corona Corona Corona Pål Brekke, Norwegian Space Centre/UNIS
66 Norwegian participation i NASAs IRIS NASA SMEX solar mission to be launhed in built by Lockheed Palo Alto Super high spatial and temoral resolution Norwegian scientists at UiO involved Data download at SVALSAT - financed by Norwegian PRODEX (ESA) funding
67 Front page in Science
68 Planned Future International Solar Missions Solar Orbiter [2017+] ESA (+NASA) Out of Eccliptic, Far-Side, Co-Rotation, Inner Heliosphere/Corona Solar Probe - NASA A Closer look Solar Sentinels NASA. Multipoint Inner Heliosphere
69 Solar Orbiter: Close- up Imaging and spectroscopy, due to proximity, with an order of magnitude improvement over past missions SOHO/EIT TRACE Solar Orbiter 1850 km pixels 350 km pixels 35 km pixels
70 International Living With a Star Some candidate missions In the years ahead, portions of this spacecraft fleet will be configured into constellations - smart, strategically-located satellites that can work together to provide the timely, on-demand data and analysis to users who enable the practical benefits for scientific research, national policymaking, economic growth, hazard mitigation and the exploration of other planets in this solar system and beyond.
71 International Living With a Star