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EXTRASOLAR PLANETARY SYSTEMS DETECTION METHODS, RESULTS AN EASY INTRODUCTION AND EVERYBODY PERSPECTIVES FOR MICHAŁ RÓŻYCZKA NICOLAUS COPERNICUS ASTRONOMICAL CENTER 1ST PLANETS SHOOL, HEIDELBERG, OCT. 8TH, 2003 • The first discoveries • Observing planet formation • Detecting „mature” planets • Statistics of extrasolar systems • Future space missions THE FIRST DISCOVERIES 1ST EXTRASOLAR PLANETARY SYSTEM ANNOUNCED IN JANUARY 1992 ALEX WOLSZCZAN 2 PLANETS (NOW 3) 1600 LIGHT YEARS FROM THE SUN CONSTELLATION VIRGO PSR 1257+12 A B C SUN DISTANCE (EARTH = 1) MERCURY VENUS EARTH PSR 1257+12 A B C SUN DISTANCE (EARTH = 1) MERCURY VENUS EARTH ... BUT CERTAINLY THE FIRST ... BUT RATHER SURPRISING EXTRASOLAR SYSTEM : PROMISING GLORIOUS... UNFRIENDLY 1ST PLANET AT A SOLAR-LIKE STAR ANNOUNCED IN OCTOBER 1995 LONG BEFORE THAT MICHEL MAYOR STARBIRTH-PROCESSES DIDIER QUELOZ HAVE BEEN STUDIED, YIELDING CLUES STAR 51 PEGASI ABOUT 40 LIGHT YEARS FROM THE SUN CONSTELLATION PEGASUS PLANET FORMATION OBSERVING PLANET FORMATION (INDIRECTLY) 50 000 LIGHT YEARS 25 000 LIGHT YEARS 1011 STARS MILKY WAY – STARS ONLY MILKY WAY – VISIBLE LIGHT MILKY WAY - INFRARED CO, 2.64 mm 3-6×109 M 3×105 M mostly H2 300 l.y. INFRARED CO ORION STAR-FORMING REGION ORION NEBULA VISIBLE 2.5 l.y. INFRARED ORION NEBULA AGE: A FEW MILLION YEARS 150 objects R = 50 -1000 AU M > 600 M (H2 emission; absorption of visible light emitted by the nebula ) M > 2000 M Concave Disk b Pictoris 63 l.y. 1.7 M 50 AU AGE: 108 years dust mass: 0.1 M gas mass: 100 M Infrared 1,2m resolution 0,12’’ THE STARS DISCS ARE DISPERSE BORN DETAILS OF STAR DISC AND WITHIN DISC WITHFORMATION DISPERSAL CIRCUMSTELLAR ~ 107 YEARSDISCS UNKNOWN RESIDUAL DISCS SEEM TO CONTAIN MORE THAN JUST DUST A PLANET? WARP b Pictoris FOMALHAUT 25 l.y. 2.8 M AGE: 108 years dust mass: 0.1 M HOLE HOLE WARP OUTER PLANET INNER PLANET(S)? OUTER PLANET? INDIRECT EVIDENCE: PLANETS RESIDUAL DISCS CONTAIN DETECTING MATURE PLANETS JUPITER SHINES WEAKER THAN THE SUN: 1 000 000 000 TIMES 50 000 TIMES 5 000 TIMES (visible light) (infrared) (mm and sub-mm) JUPITER OBSERVED FROM THE NEAREST STAR 0.1” DISTANT FROM THE SUN „DROWNED” IN SUNSHINE !! PSF, SEEING, ZODIACAL LIGHT, BACKGROUD SKY REMNANT DISK AND YET WITHIN THE LAST 8 YEARS HOW ?? MORE THAN 110 EXTRASOLAR PLANETS HAVE BEEN FOUND POPULAR VIEW POPULAR VIEW REALITY X = CENTER OF MASS SYSTEM VIEWED POLE-ON (RARE) REALITY SYSTEM VIEWED OBLIQUELY (MORE COMMON) THE PLANET CANNOT BE SEEN ...BUT MOTIONS OF THE STAR BETRAY ITS PRESENCE ! 450 km 9 cm/s 150 000 000 km 30 km/s X EARTH 750 000 km 13 m/s JUPITER X 780 000 000 km 13 km/s MOTIONS OF THE SUN VIEWED FROM A STAR 30 LIGHT YEARS AWAY 2020 1995 2010 1990 0.002’’ IS THE ANGULAR SIZE OF A MAN ON THE MOON OR A STANDARD NEWSPAPER FONT 300 KM AWAY 2015 2000 0.002” 2005 STELLAR WOBBLE RECEDING: REDDER APPROACHING: BLUER 1 Angstrom = 10-8 cm PLANET DETECTION DUE TO STELLAR WOBBLE 100 m/s P normal to the orbit i to the observer 50 K 0 V -50 -100 0 1 2 days 3 K = Vsin i PLANET DETECTION DUE TO STELLAR WOBBLE MK /(sin i VPL) MPL sin i = MK / VPL K = V sin i KNOWN: 1. ORBITAL PERIOD 2. AMPLITUDE OF VELOCITY VARIATIONS 3. MASS OF THE STAR * COMPUTED: 1. MASS OF THE PLANET (LOWER LIMIT) 2. ORBITAL RADIUS ANOTHER EFFECT: TRANSIT PLANET IN FRONT OF THE STAR TRANSIT BRIGHTNESS LIGHT CURVE 1% TIME FIRST DETECTION OF A PLANET VIA THE TRANSIT PHENOMENON ANNOUNCED IN 2002/2003 ANDRZEJ UDALSKI MACIEJ KONACKI STAR OGLE-TR-56 ~5000 LIGHT YEARS FROM THE SUN CONSTELLATION SAGITTARIUS KNOWN: 1. ORBITAL PERIOD 2. AMPLITUDE OF VELOCITY VARIATIONS 3. MASS OF THE STAR 4. LIGHT CURVE COMPUTED: 1. MASS1.OF MASS THE OF PLANET THE PLANET (LOWER LIMIT) 2. RADIUS AND SHAPE OF THE ORBIT 3. RADIUS OF THE PLANET BASIC STATISTICS OF EXTRASOLAR PLANETS excentricity e data from February 2001 b a e=(a2-b2)1/2/a semimajor axis (AU) ASTRONOMICAL UNITS COMPOSITE EXTRASOLAR SYSTEM -1 EARTH’S ORBIT ASTRONOMICAL UNITS COMPOSITE EXTRASOLAR SYSTEM -2 ASTRONOMICAL UNITS MERCURY’S ORBIT EARTH’S ORBIT JUPITERS” „ ASTRONOMICAL UNITS DEEP INSIDE MERCURY’S ORBIT !!! Planetary system of u And 0.85 AU 242 days 2 MJ 0.06 AU 4.5 days 0.75 MJ 0.39 AU 89 days 0.73 AU 228 days 1 AU 1 year 2.5 AU 3.5 years 4 MJ 1.54 AU 1.9 years Solar system Source: Harvard-Smithsonian CfA EXPECTED: NEARLY CIRCULAR ORBITS BIG PLANETS FAR AWAY FROM THE STAR NO PLANETS BIGGER THAN JUPITER DISCOVERED: STRONGLY ELONGATED ORBITS BIG PLANETS VERY CLOSE TO THE STAR MANY PLANETS BIGGER THAN JUPITER CONCLUSION ARE THERE WHO WE ARE: SOME PLANETARY SYSTEMS HAVE FORMED AND/OR EVOLVED ANY EARTH-LIKE ENTIRELYSTANDARD DIFFERENTLY COSMIC PLANETS THAN THE SOLAR SYSTEM AT DISTANT STARS? OR COSMIC QUESTIONS: EXCEPTION? Distribution of masses of known extrasolar planets. About 1000 stars have been surveyed: a nearly complete sample of solar-type stars within 30 pc. Occurrence varies inversely with mass. PLANETS AND METALLICITY FUTURE SPACE MISSIONS RELATED TO EXTRASOLAR PLANETS SIRTF 3.09.2003 INFRARED This engineering image is a quick look at the sky through LAUNCH: the Infrared ArrayTH Camera AUGUST (IRAC), one of 25 three scientific instruments aboard SIRTF. The instrument was powered on for a brief electronics checkout, and some imagesof the sky were taken to test whether the IRAC detectors were functioning. The 5 arcmin x 5 arcmin image was taken in a low Galactic latitude region in the constellation Perseus. PROTOSTARS PTOTPLANETARY DISCS COROT, KEPLER, EDDINGTON LAUNCH IN 3-5 YEARS TRANSITS SEARCH FOR EARTH-LIKE PLANTES SIM LAUNCH IN ~6 YEARS WOBBLE DUE TO EARTH-LIKE PLANTES STELLAR MASS ( M) B 0.01 0.1 ORBITAL PERIOD (YEARS) 10 100 1000 1 10 Main Sequence A habitable zone F 1 Solar System G K M 0.1 0.001 Kepler search space 0.01 STELLAR RADIUS 0.1 1 ORBITAL RADIUS (AU ) 10 100 DARWIN INTENSITY LAUNCH IN MIN. 11 YEARS × 1/10 000 cm DIRECT OBSERVATIONS OF EARTH-LIKE PLANETS the of lifereview on another Thediscovery 2001 decadal of planet is potentially one of the astronomy and astrophysics, most important prepared by thescientific U.S. National advances this century Researchof Council, stated that: it would have enormous philosophical implications IN MORE PRACTICAL TERMS: PLANETS ATTRACT MONEY LIGHT YEARUNIT ASTRONOMICAL 1l.y. = 63000 115000 AUkm 1AU = 150 13 = 10 km = 8.3 light minutes