Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
Space-based Observational Astronomy
Prof. Dr. Şölen Balman
METU
◗ Astronomy & Astrophysics is the study of space outside our atmosphere.
◗ What can we see when we look at the sky on a clear night ?
Twinkle Twinkle little star ?….Planets….. Satellites!!…comets...meteor showers…..
◗ Where are we located ?Where are we located ? Earth !!!Earth !!! Solar SystemSolar System
Milkyway GalaxyMilkyway Galaxy
Local GroupLocal Group
Local Super Cluster Local Super Cluster
Great Attractor (Wall)Great Attractor (Wall)
UniverseUniverse
How Do We View the Sky ?
The Solar System --- FormationThe Solar System --- Formation
Size = 80 A.U. 1 A.U.=1.5x1013 cm
MILKY WAY GALAXY ---- SIDE VIEW
1 pc = 3.09x1018 cm ≃ 3.26 ly ---- 1kpc = 1000 pc
1 ly = c t = 3x1010 cm/s 3x107 sec = 9x1017 cm
GALAXY FORMATIONGALAXY FORMATION
View of our Galaxy as we View of our Galaxy as we observe it through Telescopesobserve it through Telescopes
LOFAR is the largest connected radio telescope ever built,using a new concept based on a vast array of omni-directional antennas. The project is based on an interferometric array of radio telescopes using about 25,000 small antennas concentrated in at least 48 larger stations. 40 of these stations are distributed across the Netherlands, five stations in Germany, and one each in Great Britain, France and Sweden. The total effective collecting area is up to approximately 300,000 square me meter.
408 Mhz
THE LOCAL GROUP ---- 20-30 galaxies
THE LOCAL SUPER CLUSTERTHE LOCAL SUPER CLUSTER
------ 200 Million LY IN SIZE
HOSTS OVER A MILLION
GALAXY
CLUSTERS
2 Micron All-Sky Redshift Survey
This survey aims to map the distribution of galaxies and dark matter in the local universe, out to a mean redshift of z = 0.03 (roughly equivalent to 115 Mpc or 370 million light-years). Out to a Limiting magnitude of K=11.8 is used and 45000 galaxies is displayed. Red are the farthest objects with redshift around 0.07 and blue toviolet are the lowest reshift objects that are closest.
Visiable Universe out to 600 Mpc
OUR VISOR OF THE UNIVERSE : TELESCOPES
Why do we need Telescopes ?◗ Large collection area◗ long integration time◗ Magnification◗ Resolution --- Θ = λ / D
Transmission of the Atmosphere --- Why do we need telescopes in space ?
REFLECTORSREFLECTORS
REFRACTORSREFRACTORS
AND AND
DIFFERENTDIFFERENT
WAVELENGTHWAVELENGTH
CONFIGURATIONSCONFIGURATIONS
ARECIBOARECIBO -- 300m300m
Radio wavelengthsRadio wavelengths
3.5 m -- CTIO Chile3.5 m -- CTIO Chile
optical wavelengthsoptical wavelengths
Very Large Array, New Mexico USA
TWIN KECK TelescopesMulti-mirror telescopeMount Kea Hawaii10 m each mirror with 36 segments of 1.8m mirrors
AUXILLIARY INSTRUMENTS◗ Guiding Systems◗ Cameras◗ Cooling Systems◗ Spectrographs (gratings that disperse light in
wavelength)◗ Detectors
Charge Coupled Devices (CCD)
Scintillation Counters
Proportional Counter Arrays
Multi-Channel Plates
OBSERVATORIES IN SPACE
◗ Microwave : COBE -- WMAP ◗ Infra Red : IRAS, ISO – SPITZER,
Planck, Herschel◗ Optical : HST◗ Ultra Violet : IUE, EUVE – FUSE, GALEX◗ X-Ray : ROSAT, ASCA, Beppo-Sax--
RXTE, Chandra, Suzaku, XMM-Newton◗ Gamma-Ray : GRO -- INTEGRAL, SWIFT,
Fermi, AGILE
CHANDRA OBSERVATORY 0.1 -- 10 keV
July 199910mx1.2m4790 kg133000 km-16000 km64.2 hours
CHANDRA CHANDRA SCIENCE: DATA SCIENCE: DATA AND SPECTRAAND SPECTRA
Chandra X-Ray Observatory -- 0.1-10 keV
Crab Nebula CAS A
Galactic Plane
Chandra X-Ray Observatory
CXChttp://chandra.harvard.edu
HUBBLE SPACE TELESCOPEHUBBLE SPACE TELESCOPE
April 1990 - today
2.4 m mirror size
0.05 arcsec resolution
11110 kg – 559 km
97 minutes
HST STIS DATA AND SPECTRAHST STIS DATA AND SPECTRA
HST HERITAGEHST HERITAGE
MULTIWAVELENGTH STUDIES MULTIWAVELENGTH STUDIES