Shadow Imaging of Geosynchronous Satellites

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Shadow Imaging of Geosynchronous Satellites"

Transcription

1 Shadow Imaging of Geosynchronous Satellites AFOSR Workshop, Maui Dennis Douglas Bobby Hunt David Sheppard Integrity Applications Incorporated Sept 17 th, 2016 United States Air Force Office of Scientific Research (AFOSR) Grant FA C-0035 Dr. Stacie Williams

2 Outline Top Level Basic Research Objectives Part I: Overview of Shadow Imaging Part II: Basic Research Objectives and Progress Part II-a: Shadow Science and Simulation Part II-b: Shadow Image Processing Part II-c: Shadow Prediction Part III: Summary and Path Forward

3 Part I Overview of Shadow Imaging

4 Motivation and Significance Space Situational Awareness Based Resolved imaging of LEO satellites is routinely performed LEO satellite orbits at range of 160 km to 2000 km Ground based telescopes 1 m aperture using AO/MFBD/speckle imaging techniques Resolved imaging of GEO satellites is not practical using conventional imaging techniques GEO satellite orbits at range of ~ 36,000 km from Earth surface at the equator Ground based telescopes can detect solar illuminated GEO satellites but lack resolved imaging capability due to the extended range Brief history of shadow observations from stellar occultations Shadow observations are routinely performed by the professional and amateur astronomical community (Kuiper belt objects, asteroids, exoplanet detection) 1D The extension of shadow imaging to GEO satellites has been examined only to a limited degree and has not been demonstrated to date Only two published papers exist prior to 2014 that specifically address shadow imaging as a means of obtaining resolved images of GEO satellites (Burns, et al 2005 & Luu, et al 2008)

5 Classical Spatial Resolution Limits At GEO Distance of 36,000 km AEOS / Starfire Keck TMT

6 2D GEO Shadow Observation

7 Far Field Near Field GEO Shadows are Typically in the Fresnel Region and Traverse the Earth at High Velocities GEO distance bound by solid and dashed lines N f = a2 λz

8 Part II-a Shadow Science and Simulation Development

9 Simulation Step 1 True Ground Irradiance Spectral Binning

10 Simulation Step 2 Measurement Inferred Ground Irradiance

11 Baseline Simulation Parameters

12 Satellite Model and Varied Parameters for Simulation Cases

13 Ground Irradiance Map Zoomed View: 100x100 m 28x28 m W/m 2 W/m 2 28 m 28 m 28 m 28 m

14 Signal to Noise Ratio Profile through Center Row

15 Part II-b Shadow Image Reconstruction

16 Reconstruction Step 1 Multi Step Fresnel Integral version of Gerchberg Saxton Phase Retrieval Algorithm Multi-Step Fresnel Multi-Step Inverse Fresnel

17 Reconstruction Step 2 Sum Wavelength Block Reconstructions

18 Reconstructed Images All Simulation Cases: Zoomed to 28x28 m High SNR (mv=8, D=0.4m) Low SNR (mv=11, D=0.4m) High SNR (mv=8, D=0.8m)

19 Enlarged Display of Sim Cases 3A and 3B With and Without Star Phase Compensation

20 Resolution Limits For Each Simulation Case 0.4 m Apertures 0.8 m Apertures

21 Part II-c Shadow Prediction Macroscopic Density Maps & Localized Shadow Tracks

22 Shadow Prediction Process Proper Motion of Stars and Satellite Positions Known Step 1 Earth Spheroid Intersection Calculation Step 2 Refraction Calculation Step 3 Displacement Calculation Step 4 Site Location Calculation Step 1 Step 2 Step 3 Step 4 No Atmosphere Vector from occulted star to satellite normalized to unit length Pucinelli algorithm provides intersection with the spheroid directly WGS-84 Earth model Compute height of reduced atmosphere Compute index of refraction of air (P, T, λ) Compute refraction at the upper atmosphere boundary using Cassini s equation This is an exact geometric solution Vallado sensor boresight calculations are used (11.3) Solving for Range Angle Λ max Λ min Spherical earth assumption reasonable for very small displacements Computations are localized with site distance from center of earth Angular displacement converted to distance on the earth surface Displacement is in the azimuth direction to the satellite from the observer Latitude and longitude are computed of new site are computed

23 Macroscopic Shadow Density Map Night of Jan 19 th, 2016: Shadow Tracks for Single GEO Satellite = Galaxy3C Elevation Look Angle >= 15 o Stellar Visual Magnitude Range m v = [2,8] This is a 2-D histogram with bin sizes 1 X 1 degrees Lat/Lon. Each bin count has been normalized by the area of its quadrangle on the earth ellipsoid. This is for one 24-hour period.

24 Macroscopic Shadow Density Map Night of Jan 19 th, 2016: Shadow Tracks for Single GEO Satellite = Galaxy3C Elevation Look Angle >= 15 o Stellar Visual Magnitude Range m v = [2,10] This is a 2-D histogram with bin sizes 1 X 1 degrees Lat/Lon. Each bin count has been normalized by the area of its quadrangle on the earth ellipsoid. This is for one 24-hour period.

25 Total Night Occultations Vs. Time Lots of Shadows in a Single Night for GEO Satellite Galaxy 3C Night of Jan 19 th, 2016 Night Day Night Visual Magnitude The horizontal axis spans a 24-hour period with 0.5 second time steps. Includes a minimum observer elevation look angle of 15 degrees. Lots of Shadows from Single GEO Satellite

26 Localized Nominal Shadow Tracks Assumes no Astrometric Uncertainties Shadow tracks over 2 x 2 km area in Kihei, HI for the of night of Jan. 19th, 2016 from GEO satellite YAMAL 300K Red dots are computed shadow locations at a 0.1 s time step. The blue lines are interpolated Imagery is from the USGS Orthographic 1-foot database The viewing elevation angle is limited to be greater than 15 degrees Star magnitudes from [2,10] considered 25 shadow GEO satellite tracks in this scenario

27 Astrometric Errors Influence on Ground Shadow Track Uncertainty Two shadow tracks from upper right of previous slide Monte Carlo of each shadow ground track position using 100 trials Lower track uses a stellar position uncertainty of 9 mas, yielding a shadow track uncertainty of =2 m Upper track uses a stellar position uncertainty of 110 mas, yielding a shadow track uncertainty of =24 m

28 GEO Occultation Events over a Year Temporal Morphology Attributed to View Angle with Respect to Galactic Plane Orientation GEO Satellite Galaxy 3C x-axis: 1 sec time steps Animation in 10 days steps Star mags [2,8] Elevation angle >15 deg

29 Part III Summary and Path Forward

30 Summary and Future Research Shadow Simulation Supports diverse observing scenarios Implement deep turbulence models Implement additional detector technology (RULLI, LANL N-Cam, standard types) Optimize collection parameters based on observing scenario Shadow Image Processing Fresnel integral version of G-S algorithm Sub meter resolution readily attainable given sufficient SNR Poisson Maximum Likelihood Estimation (PMLE) for optimal reconstruction Shadow prediction Global shadow density maps Localized shadow track prediction Extend to multiple satellites (density maps and localized track views) Implement soon to be released Gaia star catalog (less astrometric error for stars) Further quantify collection opportunity versus system mobility Capture GEO satellite shadow using single aperture Thank You: United States Air Force Office of Scientific Research (AFOSR) grant FA C-0035 Dr. Stacie Williams

31 Backup Slides

32 Satellite Plane Propagation Planes and Distances Satellite to Top of Atmosphere Vacuum Top of Atmosphere to Ground 10 Phase Screens Applied

33 Developments in Previously Published work on GEO Satellite Shadow Imaging Burns, et al. Sizes of GEO satellites and distance are consistent with Fresnel region diffraction pattern on Earth using visible wavelengths Gerchberg-Saxton phase retrieval algorithm can be used to reconstruct the satellite image from diffraction pattern Probability of a GEO satellite shadow crossing a linear array of collection apertures is significantly increased if the collection system is placed on a mobile platform that moves along the north/south direction Luu, et al. Spectrally resolved shadow imaging introduced to increase spatial resolution Wavelength binning instead of single wide band collection Each bin reconstructed independently then stacked for final image Shadow imaging shown to be very resilient to atmospheric turbulence

34 Exposure Time Determined by Transit Time over Single Collection Aperture Collected Light is Binned into Spectral Blocks Given total spectral range: a b Single binned spectral block width: K Number of Spectral Blocks: J = ( b - a) / K Single Spectral Block: j Λ 1 Det 1 Single Collection Aperture Λ 2 Det 2 Λ 3 Det 3 Λ J Det J

35 Development of End-to-End Shadow Imaging Simulation Capability Source Star Attributes Brightness Angular extent GEO Satellite Geometry Symmetry and feature sizes Environmental Parameters Atmospheric attenuation/refraction/dispersion/turbulence Light Collection Parameters Diameter of each individual collection aperture Spatial sampling of shadow collection Spectral binning associated with each collection aperture GM-APD Measurement Parameters Photon detection efficiency Noise: dark count rate and afterpulsing Timing errors in synchronization An end-to-end simulation was constructed to quantify the impact of each of these factors using a rigorous treatment of the GM-APD measurement process

36 Sampling in Propagation Planes Fixed Grid Spacing Sampling criteria using Fresnel transfer propagation kernel

37 Equatorial Coordinates for Tycho-2 Stars Right Ascension and Declination

38 Density of Stars in the Sky Equatorial and Galactic Coordinate Systems

39 Brightness of Tycho-2 Stars V Magnitude

40 Angular Extent of Largest Stars in the Sky Vast majority of stars

41 Fresnel Impulse Response Function Fresnel Transfer Function used as Light Propagation Kernel Fresnel Transfer Function (Angular Spectrum) Equivalent Analytic Implementations Transfer Function Method used in Numerical Propagation Propagation of polychromatic light

42 Spectral Irradiance of Vega used as Radiometric Basis Data from Space Telescope Science Institute AB magnitude of Vega Spectral irradiance at satellite Electric field amplitude at satellite

43 Angular Extent of Star Applied as Phase Term Continuum of Tilted Plane Waves Tilt Term Star Phase at Satellite Radial Integral of Tilt Term Complex Electric Field at Satellite

44 MODTRAN used for Nominal Atmospheric Transmission Scaled by Airmass per Off Zenith Pointing (approximation) Airmass Scaled atm. transmission

45 Atmospheric Refraction 500 nm Light

46 Atmospheric Dispersion Centered at 500 nm Light

47 Atmospheric Refractive Index Structure Constant versus Altitude Hufnagel-Valley 5/7 Profile

48 Atmospheric Turbulence Applied to Electric Field as Phase Term Atm. coherence length (Fried parameter) Spatial frequency PSD Phase from single atm. layer Phase applied to electric field

49 Notation used to Define Propagation Planes

50 Avalanche Photo Diode Basics Linear and Geiger Modes: Photon Counting Device GM-APD measurement process is inherently different from a CCD or CMOS detector APD: Reverse bias PN junction with strong electric field Photo generated electrons gain sufficient kinetic energy to free other electron through collisions (avalanche effect) Breakdown voltage: balance of electron creation and loss through current Linear mode (LM) operates below the breakdown voltage current is linear with incident light flux GM-APD: Operates above the breakdown voltage electron population grows exponentially (avalanche) Binary operation (avalanche or no avalanche within gate time) Avalanche probability over many samples calculated and used to estimate flux

51 Overview of GM-APD Parameters Dead Time (t d ): Time it takes the GM-APD to be quenched after an avalanche and then returned to nominal geiger mode Gate Time (t g ): Time in which the device is in the nominal steady state and capable of detecting an avalanche event Number of Gates (n g ): Number of measurement windows within the total exposure time Exposure Time (t): The exposure time is the duration of the device measurement and consists of multiple discrete units of t g + t d Photon Detection Efficiency (P d ): Combines the quantum efficiency (QE) and spatially dependent detection efficiency on the active area of the GM- APD pixel Dark Count Rate (N D ): Number of excited electrons that trigger an avalanches without a photon being absorbed Afterpulsing (P ap ): : Probability of the release of a previously "trapped" electron that causes an avalanche within a single gate time

52 Signal to Noise Ratio for GM-APD Actively Quenched Gated Mode Operation Signal photons per gate Background photons per gate Signal photon rate Dark noise detections per gate Effective photons per gate Sky background photon rate

53 Numerical Simulation of GM-APD Measurement Process with No Afterpulsing Probability that single gate has n p photons given by Poisson distribution: Bernoulli trial determines if the i th gate records an avalanche (each gate is independent) Random number generated from binomial distribution Number of recorded avalanches over exposure time Inferred photon fluence Binary measurement of avalanche occurrence within each gate Inferred photon fluence

54 Photon Fluence to GM-APD Pixel Source Star Magnitude and Collection Aperture Diameter Fluence # photons/pixel/s

55 Impact on SNR based on GM-APD Parameters and Photon Fluence

56 Two GM-APD Detector Baselines A = Current Capability, B = Near Future Capability

57 SNR versus Photon Fluence Using Baseline GM-APD Detectors

58 SNR versus Photon Fluence Low Fluence Region with Ideal Detector Comparison

59 Simulation Group 6 Large Angular Extent of Source Star Applied

60 Timing Error Modeled as Displacement in Collection Aperture Position

61 Example of Image Reconstruction based on Number of Wavelength Blocks

62 Aperture Size Impacts Fidelity of Collected Diffraction Pattern Self Normalized Collected Irradiance Shown Satellite Transmission Function Intensity ripples lost as collection aperture size increases

63 Conclusion Set I Shadow Imaging Resolution Limits using a Bright Source Star Sub Meter Resolution Readily Achieved using Small Apertures Very large telescope diameter required to achieve similar capability

64 Conclusion Set II Shadow imaging is shown to be insensitive to satellite shape and geometry Modest atmospheric turbulence is confirmed to have very little impact on shadow imaging performance Timing errors on the order of have small impact on shadow imaging performance. When the timing error reaches a value of resolution is limited to D a A source star with an angular extent of 10 nrad is shown to negatively impact shadow imaging resolution. At 20 nrad the image quality is significantly degraded.

65 Conclusion Set IV SNR Thresholds Single wavelength block SNR < 1 is shown to yield low contrast 1 meter resolvable features Based on results from Simulation Group 8 Reconstructed image corresponds to red SNR line on left plot

66 Conclusion Set V Source Star Brightness Resolvable features of 1 meter readily attained for a source star brightness down to m v = 10. Limit of 1 meter feature size resolvability near m v = 11 Based on results from Simulation Group 8 Resolvable Spatial Feature Size Approximately 873,000 potential source stars with m v 11 Approximately 1,400,000 potential source stars with m v 11.5

Shadow Imaging of Geosynchronous Satellites: Simulation, Image Reconstruction, and Shadow Prediction

Shadow Imaging of Geosynchronous Satellites: Simulation, Image Reconstruction, and Shadow Prediction Shadow Imaging of Geosynchronous Satellites: Simulation, Image Reconstruction, and Shadow Prediction Dennis M. Douglas 1 Bobby R. Hunt 1 David G. Sheppard 1 1 Integrity Applications Incorporated, 535 Lipoa

More information

SHADOW IMAGING OF GEOSYNCHRONOUS SATELLITES

SHADOW IMAGING OF GEOSYNCHRONOUS SATELLITES SHADOW IMAGING OF GEOSYNCHRONOUS SATELLITES by Dennis Michael Douglas Copyright Dennis Michael Douglas 2014 A Dissertation Submitted to the Faculty of the COLLEGE OF OPTICAL SCIENCES In Partial Fulfillment

More information

Copyright 2016 Advanced Maui Optical and Space Surveillance Technologies Conference (AMOS)

Copyright 2016 Advanced Maui Optical and Space Surveillance Technologies Conference (AMOS) Application of satellite laser ranging techniques for space situational awareness efforts M. Shappirio, NASA Goddard Space Flight Center J.F. McGarry, NASA Goddard Space Flight Center J. Bufton, Global

More information

DOME C AS A SETTING FOR THE PERMANENT ALL SKY SURVEY (PASS)

DOME C AS A SETTING FOR THE PERMANENT ALL SKY SURVEY (PASS) Title : will be set by the publisher Editors : will be set by the publisher EAS Publications Series, Vol.?, 2005 DOME C AS A SETTING FOR THE PERMANENT ALL SKY SURVEY (PASS) H.J. Deeg, J.A. Belmonte, R.

More information

ADVANCED CCD PHOTOMETRY AND EXOPLANET TRANSIT PHOTOMETRY. By : Kenny A. Diaz Eguigure

ADVANCED CCD PHOTOMETRY AND EXOPLANET TRANSIT PHOTOMETRY. By : Kenny A. Diaz Eguigure ADVANCED CCD PHOTOMETRY AND EXOPLANET TRANSIT PHOTOMETRY By : Kenny A. Diaz Eguigure KELT: THE KILODEGREE EXTREMELY LITTLE TELESCOPE Robotic Survey for Transiting Exoplanets KELT-North Deployed 2005 to

More information

High Precision Exoplanet Observations with Amateur Telescopes

High Precision Exoplanet Observations with Amateur Telescopes High Precision Exoplanet Observations with Amateur Telescopes Dennis M. Conti Chair, AAVSO Exoplanet Section Member, KELT Follow-up Team Member, TESS TFOP Working Group HAL Meeting: October 19, 2017 1

More information

Observation of Light Curves of Space Objects. Hirohisa Kurosaki Japan Aerospace Exploration Agency Toshifumi Yanagisawa.

Observation of Light Curves of Space Objects. Hirohisa Kurosaki Japan Aerospace Exploration Agency Toshifumi Yanagisawa. Observation of Light Curves of Space Objects Hirohisa Kurosaki Japan Aerospace Exploration Agency Toshifumi Yanagisawa Japan Aerospace Exploration Agency Atsushi Nakajima Japan Aerospace Exploration Agency

More information

Chapter 6 Telescopes: Portals of Discovery

Chapter 6 Telescopes: Portals of Discovery Chapter 6 Telescopes: Portals of Discovery 6.1 Eyes and Cameras: Everyday Light Sensors Our goals for learning: How does your eye form an image? How do we record images? How does your eye form an image?

More information

Chapter 5: Telescopes

Chapter 5: Telescopes Chapter 5: Telescopes You don t have to know different types of reflecting and refracting telescopes. Why build bigger and bigger telescopes? There are a few reasons. The first is: Light-gathering power:

More information

Answer Key for Exam C

Answer Key for Exam C Answer Key for Exam C 1 point each Choose the answer that best completes the question. Read each problem carefully and read through all the answers. Take your time. If a question is unclear, ask for clarification

More information

Chapter 6 Telescopes: Portals of Discovery. Agenda. How does your eye form an image? Refraction. Example: Refraction at Sunset

Chapter 6 Telescopes: Portals of Discovery. Agenda. How does your eye form an image? Refraction. Example: Refraction at Sunset Chapter 6 Telescopes: Portals of Discovery Agenda Announce: Read S2 for Thursday Ch. 6 Telescopes 6.1 Eyes and Cameras: Everyday Light Sensors How does your eye form an image? Our goals for learning How

More information

Joint R&D and Ops: a Working Paradigm for SSA

Joint R&D and Ops: a Working Paradigm for SSA Joint R&D and Ops: a Working Paradigm for SSA 23 July 2017 Stacie Williams Program Officer Air Force Office of Scientific Research Integrity «Service «Excellence Air Force Research Laboratory 1 2 Joint

More information

Infrared Earth Horizon Sensors for CubeSat Attitude Determination

Infrared Earth Horizon Sensors for CubeSat Attitude Determination Infrared Earth Horizon Sensors for CubeSat Attitude Determination Tam Nguyen Department of Aeronautics and Astronautics Massachusetts Institute of Technology Outline Background and objectives Nadir vector

More information

Some Issues of Creation of Wide-Field Telescopes for Monitoring Satellites and Space Debris in High Earth Orbits. Maui, Hawaii, April 2010

Some Issues of Creation of Wide-Field Telescopes for Monitoring Satellites and Space Debris in High Earth Orbits. Maui, Hawaii, April 2010 Some Issues of Creation of Wide-Field Telescopes for Monitoring Satellites and Space Debris in High Earth Orbits I. Tarasenko (1), V. Terebizh (1), S. Markelov (2) (1) Open Joint tstock kcompany Research-and-Production

More information

Refraction is the bending of light when it passes from one substance into another. Your eye uses refraction to focus light.

Refraction is the bending of light when it passes from one substance into another. Your eye uses refraction to focus light. Telescopes Portals of Discovery Chapter 6 Lecture The Cosmic Perspective 6.1 Eyes and Cameras: Everyday Light Sensors How do eyes and cameras work? Seventh Edition Telescopes Portals of Discovery The Eye

More information

Fundamentals of Exoplanet Observing

Fundamentals of Exoplanet Observing Fundamentals of Exoplanet Observing Dennis M. Conti Chair, AAVSO Exoplanet Section Copyright Dennis M. Conti 2017 1 The Strange World of Exoplanets Most exoplanets we have discovered are close-in, large

More information

Fundamentals of Exoplanet Observing

Fundamentals of Exoplanet Observing Fundamentals of Exoplanet Observing Dennis M. Conti Chair, AAVSO Exoplanet Section Copyright Dennis M. Conti 2017 1 The Strange World of Exoplanets Most exoplanets we have discovered are close-in, large

More information

Dr. Linlin Ge The University of New South Wales

Dr. Linlin Ge  The University of New South Wales GMAT 9600 Principles of Remote Sensing Week2 Electromagnetic Radiation: Definition & Physics Dr. Linlin Ge www.gmat.unsw.edu.au/linlinge Basic radiation quantities Outline Wave and quantum properties Polarization

More information

Characterisation of Silicon Photomultipliers for the T2K Experiment

Characterisation of Silicon Photomultipliers for the T2K Experiment Characterisation of Silicon Photomultipliers for the T2K Experiment, 18th May 2010 Martin Haigh, University of Oxford Outline Brief introduction to the T2K experiment. Overall configuration and goals.

More information

Theoretical Examination

Theoretical Examination Page 1 of (T1) True or False Determine if each of the following statements is True or False. In the Summary Answersheet, tick the correct answer (TRUE / FALSE) for each statement. No justifications are

More information

Single Photon detectors

Single Photon detectors Single Photon detectors Outline Motivation for single photon detection Semiconductor; general knowledge and important background Photon detectors: internal and external photoeffect Properties of semiconductor

More information

Influence of moon light on tip-tilt sensing accuracy using STRAP

Influence of moon light on tip-tilt sensing accuracy using STRAP Keck Adaptive Optics Note 425 Influence of moon light on tip-tilt sensing accuracy using STRAP Stephan Kellner, David Le Mignant and Marcos van Dam Version 1.0: 2 October 2006 Abstract AO observations

More information

Basic Theory of Speckle Imaging

Basic Theory of Speckle Imaging 1 Basic Theory of Speckle Imaging Elliott Horch, Southern Connecticut State University 1 arcsec BU 151AB 2 Speckle Often Means Binary Stars Stellar Masses. Mass-Luminosity Relation (MLR) Initial Mass Function

More information

100 µas Astrometry with Adap2ve Op2cs on Moderate- Sized Telescopes

100 µas Astrometry with Adap2ve Op2cs on Moderate- Sized Telescopes 100 µas Astrometry with Adap2ve Op2cs on Moderate- Sized Telescopes Drs. Richard Dekany and Nick Law Caltech Optical Observatories Workshop on Astronomy with Adaptive Optics on Moderate-Sized Telescopes

More information

USAAAO First Round 2015

USAAAO First Round 2015 USAAAO First Round 2015 This round consists of 30 multiple-choice problems to be completed in 75 minutes. You may only use a scientific calculator and a table of constants during the test. The top 50%

More information

AstroBITS: Open Cluster Project

AstroBITS: Open Cluster Project AstroBITS: Open Cluster Project I. Introduction The observational data that astronomers have gathered over many years indicate that all stars form in clusters. In a cloud of hydrogen gas, laced with helium

More information

Lecture Outline: Chapter 5: Telescopes

Lecture Outline: Chapter 5: Telescopes Lecture Outline: Chapter 5: Telescopes You don t have to know the different types of optical reflecting and refracting telescopes. It is important to understand the difference between imaging, photometry,

More information

Telescopes: Portals of Discovery

Telescopes: Portals of Discovery Telescopes: Portals of Discovery How do light and matter interact? Emission Absorption Transmission Transparent objects transmit light Opaque objects block (absorb) light Reflection or Scattering Reflection

More information

Tentative observation of a gamma-ray line at the Fermi Large Area Telescope

Tentative observation of a gamma-ray line at the Fermi Large Area Telescope Tentative observation of a gamma-ray line at the Fermi Large Area Telescope arxiv:1203.1312 with T. Bringmann, X. Huang, A. Ibarra, S. Vogl (accepted for JCAP), arxiv:1204.2797 (accepted for JCAP) Christoph

More information

Introduction to SDSS -instruments, survey strategy, etc

Introduction to SDSS -instruments, survey strategy, etc Introduction to SDSS -instruments, survey strategy, etc (materials from http://www.sdss.org/) Shan Huang 17 February 2010 Survey type Status Imaging and Spectroscopy Basic Facts SDSS-II completed, SDSS-III

More information

Geostationary Satellites and Astrophotography

Geostationary Satellites and Astrophotography Geostationary Satellites and Astrophotography By Clay S. Turner 11/14/08 Introduction When I first started doing astrophotography last January, it was only natural to take pictures of some of Orion s deep

More information

Astronomy. Optics and Telescopes

Astronomy. Optics and Telescopes Astronomy A. Dayle Hancock adhancock@wm.edu Small 239 Office hours: MTWR 10-11am Optics and Telescopes - Refraction, lenses and refracting telescopes - Mirrors and reflecting telescopes - Diffraction limit,

More information

THE DYNAMIC TEST EQUIPMENT FOR THE STAR TRACKERS PROCESSING

THE DYNAMIC TEST EQUIPMENT FOR THE STAR TRACKERS PROCESSING THE DYNAMIC TEST EQUIPMENT FOR THE STAR TRACKERS PROCESSING ABSTRACT Sergey Voronkov Space Research Institute, Russian Academy of Sciences, 117997, Profsoyuznaya str., 84/32, Moscow, Russia Phone: +7 095

More information

High fidelity imaging of geosynchronous satellites with the MROI

High fidelity imaging of geosynchronous satellites with the MROI High fidelity imaging of geosynchronous satellites with the MROI John Young a, Christopher Haniff a, David Buscher a, Michelle Creech-Eakman b, and Ifan Payne b a Cavendish Laboratory, University of Cambridge,

More information

Wide and Fast: A new Era of EMCCD and CMOS?

Wide and Fast: A new Era of EMCCD and CMOS? Wide and Fast: A new Era of EMCCD and CMOS? ZTF PTF?????? Gregg Hallinan California Institute of Technology gh@astro.caltech.edu Negligible 1 sec Transient Phase Space: Mansi Kasliwal Conventional CCDs

More information

FUNDAMENTALS OF REMOTE SENSING FOR RISKS ASSESSMENT. 1. Introduction

FUNDAMENTALS OF REMOTE SENSING FOR RISKS ASSESSMENT. 1. Introduction FUNDAMENTALS OF REMOTE SENSING FOR RISKS ASSESSMENT FRANÇOIS BECKER International Space University and University Louis Pasteur, Strasbourg, France; E-mail: becker@isu.isunet.edu Abstract. Remote sensing

More information

ASTRONOMY 460: PROJECT INTRO - GALACTIC ROTATION CURVE

ASTRONOMY 460: PROJECT INTRO - GALACTIC ROTATION CURVE ASTRONOMY 460: PROJECT INTRO - GALACTIC ROTATION CURVE Snežana Stanimirović, October 6, 2014 1. Introduction This project has two goals: we want to measure the Milky Way (or Galactic) rotation curve by

More information

Speckles and adaptive optics

Speckles and adaptive optics Chapter 9 Speckles and adaptive optics A better understanding of the atmospheric seeing and the properties of speckles is important for finding techniques to reduce the disturbing effects or to correct

More information

AST111 PROBLEM SET 4 SOLUTIONS. Ordinarily the binary has a magnitude of 10 and this is due to the brightness of both stars.

AST111 PROBLEM SET 4 SOLUTIONS. Ordinarily the binary has a magnitude of 10 and this is due to the brightness of both stars. AST111 PROBLEM SET 4 SOLUTIONS Homework problems 1. On Astronomical Magnitudes You observe a binary star. Ordinarily the binary has a magnitude of 10 and this is due to the brightness of both stars. The

More information

GAMMA-RAY OPTICAL COUNTERPART SEARCH EXPERIMENT (GROCSE)

GAMMA-RAY OPTICAL COUNTERPART SEARCH EXPERIMENT (GROCSE) GAMMA-RAY OPTICAL COUNTERPART SEARCH EXPERIMENT (GROCSE) Carl Akerlof, Marco Fatuzzo, Brian Lee University of Michigan, Ann Arbor, MI 48109 Richard Bionta, Arno Ledebuhr, Hye-Sook Park Lawrence Livermore

More information

AAG TPoint Mapper (Version 1.40)

AAG TPoint Mapper (Version 1.40) AAG TPoint Mapper (Version 1.40) AAG_TPointMapper works together with Maxim DL, Pinpoint, TheSky6 and TPoint to automate the process of building a TPoint model for a GOTO telescope connected to TheSky6.

More information

Properties of Thermal Radiation

Properties of Thermal Radiation Observing the Universe: Telescopes Astronomy 2020 Lecture 6 Prof. Tom Megeath Today s Lecture: 1. A little more on blackbodies 2. Light, vision, and basic optics 3. Telescopes Properties of Thermal Radiation

More information

Equatorial Telescope Mounting

Equatorial Telescope Mounting Equatorial Telescope Mounting Star Catalogs simbad IRSA The Meridian Every line of celestial longitude is a meridian of longitude, but we recognize the line of longitude, or simply the great circle line,

More information

Creating Satellite Orbits

Creating Satellite Orbits Exercises using Satellite ToolKit (STK) vivarad@ait.ac.th Creating Satellite Orbits 1. What You Will Do Create a low-earth orbit (LEO) satellite Create a medium-earth orbit (MEO) satellite Create a highly

More information

Resolving Close Double Stars with Lunar and Asteroidal Occultations

Resolving Close Double Stars with Lunar and Asteroidal Occultations Resolving Close Double Stars with Lunar and Asteroidal Occultations David W. Dunham, IOTA and Moscow Inst. of Electronics and Mathematics/H.S.E. Maui Double Star Conference Institute for Astronomy, Maui

More information

Expected Performance From WIYN Tip-Tilt Imaging

Expected Performance From WIYN Tip-Tilt Imaging Expected Performance From WIYN Tip-Tilt Imaging C. F. Claver 3 September 1997 Overview Image motion studies done at WIYN show that a significant improvement to delivered image quality can be obtained from

More information

Analyzing Spiral Galaxies Observed in Near-Infrared

Analyzing Spiral Galaxies Observed in Near-Infrared Analyzing Spiral Galaxies Observed in Near-Infrared Preben Grosbøl European Southern Observatory Karl-Schwarzschild-Str. 2, D-85748 Garching, Germany Abstract A sample of 54 spiral galaxies was observed

More information

Whipple: Exploring the Solar System Beyond Neptune Using a Survey for Occultations of Bright Stars

Whipple: Exploring the Solar System Beyond Neptune Using a Survey for Occultations of Bright Stars Whipple: Exploring the Solar System Beyond Neptune Using a Survey for Occultations of Bright Stars Charles Alcock 1, Matthew Holman 1, Matthew Lehner 2,3,1, Stephen Murray 1, Pavlos Protopapas 1,4 and

More information

SMTN-002: Calculating LSST limiting magnitudes and SNR

SMTN-002: Calculating LSST limiting magnitudes and SNR SMTN-002: Calculating LSST limiting magnitudes and SNR Release Lynne Jones 2017-12-05 Contents 1 Source Counts 3 2 Instrumental Zeropoints 5 3 Sky Counts 7 4 Instrumental Noise 9 5 Source footprint (n

More information

Detection of Artificial Satellites in Images Acquired in Track Rate Mode.

Detection of Artificial Satellites in Images Acquired in Track Rate Mode. Detection of Artificial Satellites in Images Acquired in Track Rate Mode. Martin P. Lévesque Defence R&D Canada- Valcartier, 2459 Boul. Pie-XI North, Québec, QC, G3J 1X5 Canada, martin.levesque@drdc-rddc.gc.ca

More information

Photodiodes and other semiconductor devices

Photodiodes and other semiconductor devices Photodiodes and other semiconductor devices Chem 243 Winter 2017 What is a semiconductor? no e - Empty e levels Conduction Band a few e - Empty e levels Filled e levels Filled e levels lots of e - Empty

More information

Detection of Exoplanets Using the Transit Method

Detection of Exoplanets Using the Transit Method Detection of Exoplanets Using the Transit Method De nnis A fanase v, T h e Geo rg e W a s h i n g t o n Un i vers i t y, Washington, DC 20052 dennisafa@gwu.edu Abstract I conducted differential photometry

More information

Astr 2310 Thurs. March 3, 2016 Today s Topics

Astr 2310 Thurs. March 3, 2016 Today s Topics Astr 2310 Thurs. March 3, 2016 Today s Topics Chapter 6: Telescopes and Detectors Optical Telescopes Simple Optics and Image Formation Resolution and Magnification Invisible Astronomy Ground-based Radio

More information

Signal to Noise Comparison of IS-Instruments Ltd High Throughput OEM Spectrometer and a Czerny Turner Instrument. July 2013

Signal to Noise Comparison of IS-Instruments Ltd High Throughput OEM Spectrometer and a Czerny Turner Instrument. July 2013 Signal to Noise Comparison of IS-Instruments Ltd High Throughput OEM Spectrometer and a Czerny Turner Instrument July 2013 EXECUTIVE SUMMARY IS-Instrument s new range of High Étendue Spectrometers (HES)

More information

The table summarises some of the properties of Vesta, one of the largest objects in the asteroid belt between Mars and Jupiter.

The table summarises some of the properties of Vesta, one of the largest objects in the asteroid belt between Mars and Jupiter. Q1.(a) The table summarises some of the properties of Vesta, one of the largest objects in the asteroid belt between Mars and Jupiter. Diameter / m Distance from the Sun / AU smallest largest 5.4 10 5

More information

4. Direct imaging of extrasolar planets. 4.1 Expected properties of extrasolar planets. Sizes of gas giants, brown dwarfs & low-mass stars

4. Direct imaging of extrasolar planets. 4.1 Expected properties of extrasolar planets. Sizes of gas giants, brown dwarfs & low-mass stars 4. Direct imaging of extrasolar planets Reminder: Direct imaging is challenging: The proximity to its host star: 1 AU at 1 for alpha Cen 0.15 for the 10th most nearby solar-type star The low ratio of planet

More information

Dept. of Physics, MIT Manipal 1

Dept. of Physics, MIT Manipal 1 Chapter 1: Optics 1. In the phenomenon of interference, there is A Annihilation of light energy B Addition of energy C Redistribution energy D Creation of energy 2. Interference fringes are obtained using

More information

Telescopes: Portals of Discovery Pearson Education, Inc.

Telescopes: Portals of Discovery Pearson Education, Inc. Telescopes: Portals of Discovery 6.1 Eyes and Cameras: Everyday Light Sensors Our goals for learning: How do eyes and cameras work? The Eye Refraction Incoming light ray Air Glass Refraction is the bending

More information

Exploring Data. Keck LRIS spectra. Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6

Exploring Data. Keck LRIS spectra. Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6 Exploring Data Keck LRIS spectra Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6 FITS: Flexible Image Transport System Digital file format used to store astronomical images, data, and catalogs.

More information

What are the most important properties of a telescope? Chapter 6 Telescopes: Portals of Discovery. What are the two basic designs of telescopes?

What are the most important properties of a telescope? Chapter 6 Telescopes: Portals of Discovery. What are the two basic designs of telescopes? Chapter 6 Telescopes: Portals of Discovery What are the most important properties of a telescope? 1. Light-collecting area: Telescopes with a larger collecting area can gather a greater amount of light

More information

Characterization of the exoplanet host stars. Exoplanets Properties of the host stars. Characterization of the exoplanet host stars

Characterization of the exoplanet host stars. Exoplanets Properties of the host stars. Characterization of the exoplanet host stars Characterization of the exoplanet host stars Exoplanets Properties of the host stars Properties of the host stars of exoplanets are derived from a combination of astrometric, photometric, and spectroscopic

More information

Extraction of Point Source Spectra from STIS Long Slit Data

Extraction of Point Source Spectra from STIS Long Slit Data 1997 HST Calibration Workshop Space Telescope Science Institute, 1997 S. Casertano, et al., eds. Extraction of Point Source Spectra from STIS Long Slit Data J. R. Walsh Spect Telescope European Coordinating

More information

Brightness Measurements of Stars and the Night-Sky with a Silicon-Photomultiplier-Telescope

Brightness Measurements of Stars and the Night-Sky with a Silicon-Photomultiplier-Telescope Brightness Measurements of Stars and the Night-Sky with a Silicon-Photomultiplier-Telescope von Rebecca Meißner Bachelorarbeit in Physik vorgelegt der Fakultät für Mathematik, Informatik und Naturwissenschaften

More information

Earth-Based Support for the New Horizons Kuiper Extended Mission. Richard Binzel Alan Stern John Spencer 2016 DPS Meeting, Pasadena October18 th 2016

Earth-Based Support for the New Horizons Kuiper Extended Mission. Richard Binzel Alan Stern John Spencer 2016 DPS Meeting, Pasadena October18 th 2016 Earth-Based Support for the New Horizons Kuiper Extended Mission Richard Binzel Alan Stern John Spencer 2016 DPS Meeting, Pasadena October18 th 2016 Agenda Introduction to New Horizons Kuiper Belt Extended

More information

RADIATION DAMAGE IN HST DETECTORS

RADIATION DAMAGE IN HST DETECTORS RADIATION DAMAGE IN HST DETECTORS Marco Sirianni, European Space Agency, Space Telescope Science Institute Max Mutchler, Space Telescope Science Institute Abstract: Key words: We present an analysis of

More information

The IPIE Adaptive Optical System Application For LEO Observations

The IPIE Adaptive Optical System Application For LEO Observations The IPIE Adaptive Optical System Application For LEO Observations Eu. Grishin (1), V. Shargorodsky (1), P. Inshin (2), V. Vygon (1) and M. Sadovnikov (1) (1) Open Joint Stock Company Research-and-Production

More information

Recent Results from the ANTARES experiment

Recent Results from the ANTARES experiment Recent Results from the ANTARES experiment Manuela Vecchi on behalf of the ANTARES Collaboration University of Roma La Sapienza and INFN ICATPP09- Como: October 6th 2009 Outline -astronomy: what, where,

More information

Optical Systems Program of Studies Version 1.0 April 2012

Optical Systems Program of Studies Version 1.0 April 2012 Optical Systems Program of Studies Version 1.0 April 2012 Standard1 Essential Understand Optical experimental methodology, data analysis, interpretation, and presentation strategies Essential Understandings:

More information

Stellar Composition. How do we determine what a star is made of?

Stellar Composition. How do we determine what a star is made of? Stars Essential Questions What are stars? What is the apparent visual magnitude of a star? How do we locate stars? How are star classified? How has the telescope changed our understanding of stars? What

More information

Planets Around M-dwarfs Astrometric Detection and Orbit Characterization

Planets Around M-dwarfs Astrometric Detection and Orbit Characterization Planets Around M-dwarfs Page of 7 Planets Around M-dwarfs Astrometric Detection and Orbit Characterization N. M. Law (nlaw@astro.caltech.edu), S. R. Kulkarni, R. G. Dekany, C. Baranec California Institute

More information

Keck Adaptive Optics Note 1069

Keck Adaptive Optics Note 1069 Keck Adaptive Optics Note 1069 Tip-Tilt Sensing with Keck I Laser Guide Star Adaptive Optics: Sensor Selection and Performance Predictions DRAFT to be updated as more performance data becomes available

More information

Ay 1 Lecture 2. Starting the Exploration

Ay 1 Lecture 2. Starting the Exploration Ay 1 Lecture 2 Starting the Exploration 2.1 Distances and Scales Some Commonly Used Units Distance: Astronomical unit: the distance from the Earth to the Sun, 1 au = 1.496 10 13 cm ~ 1.5 10 13 cm Light

More information

INTER-AGENCY SPACE DEBRIS COORDINATION COMMITTEE (IADC) SPACE DEBRIS ISSUES IN THE GEOSTATIONARY ORBIT AND THE GEOSTATIONARY TRANSFER ORBITS

INTER-AGENCY SPACE DEBRIS COORDINATION COMMITTEE (IADC) SPACE DEBRIS ISSUES IN THE GEOSTATIONARY ORBIT AND THE GEOSTATIONARY TRANSFER ORBITS INTER-AGENCY SPACE DEBRIS COORDINATION COMMITTEE (IADC) SPACE DEBRIS ISSUES IN THE GEOSTATIONARY ORBIT AND THE GEOSTATIONARY TRANSFER ORBITS Presented to: 37-th Session of the SCIENTIFIC AND TECHNICAL

More information

Praktikum zur. Materialanalytik

Praktikum zur. Materialanalytik Praktikum zur Materialanalytik Energy Dispersive X-ray Spectroscopy B513 Stand: 19.10.2016 Contents 1 Introduction... 2 2. Fundamental Physics and Notation... 3 2.1. Alignments of the microscope... 3 2.2.

More information

Stellar Intensity Interferometric Capabilities of IACT Arrays*

Stellar Intensity Interferometric Capabilities of IACT Arrays* Stellar Intensity Interferometric Capabilities of IACT Arrays* Dave Kieda Nolan Matthews University of Utah Salt Lake City, Utah *for VERITAS and CTA collaborations Photon Bunching & Intensity Interferometry

More information

ME 476 Solar Energy UNIT THREE SOLAR RADIATION

ME 476 Solar Energy UNIT THREE SOLAR RADIATION ME 476 Solar Energy UNIT THREE SOLAR RADIATION Unit Outline 2 What is the sun? Radiation from the sun Factors affecting solar radiation Atmospheric effects Solar radiation intensity Air mass Seasonal variations

More information

Small Satellite Laser Comm Pointing

Small Satellite Laser Comm Pointing Small Satellite Laser Comm Pointing Darren Rowen July 11, 2016 2016 The Aerospace Corporation Agenda Optical Ground Station Tracking Demo of Cubesat Laser OCSD-B/C Design & Configuration OCSD-A Star Tracker

More information

Gaia Data Release 1: Datamodel description

Gaia Data Release 1: Datamodel description Gaia Data Release 1: Datamodel description Documentation release D.0 European Space Agency and GaiaData Processing and Analysis Consortium September 13, 2016 Contents 1 Main tables 3 1.1 gaia source...............................

More information

Sky, Celestial Sphere and Constellations

Sky, Celestial Sphere and Constellations Sky, Celestial Sphere and Constellations Last lecture Galaxies are the main building blocks of the universe. Consists of few billions to hundreds of billions of stars, gas clouds (nebulae), star clusters,

More information

Model SGS Dual CCD Self-Guiding Spectrograph

Model SGS Dual CCD Self-Guiding Spectrograph .. Model SGS Dual CCD Self-Guiding Spectrograph The Self-Guiding Spectrograph is designed to be used with the ST-7XE/XME camera. For convenience, it can also be used with any dual sensor ST/7/8/9/10/2000

More information

Autonomous Vision Based Detection of Non-stellar Objects Flying in formation with Camera Point of View

Autonomous Vision Based Detection of Non-stellar Objects Flying in formation with Camera Point of View Autonomous Vision Based Detection of Non-stellar Objects Flying in formation with Camera Point of View SFFMT 213 München May 31 st 213 Mathias Benn, As.Prof, PhD John L. Jørgensen, Prof. DTU Space Overview

More information

XENON Dark Matter Search. Juliette Alimena Columbia University REU August 2 nd 2007

XENON Dark Matter Search. Juliette Alimena Columbia University REU August 2 nd 2007 XENON Dark Matter Search Juliette Alimena Columbia University REU August 2 nd 2007 Evidence of Dark Matter Missing mass in Coma galaxy cluster (Fritz Zwicky) Flat rotation curves of spiral galaxies (Vera

More information

Satellite imaging with adaptive optics on a 1 m telescope

Satellite imaging with adaptive optics on a 1 m telescope Satellite imaging with adaptive optics on a 1 m telescope Francis Bennet, I. Price, F. Rigaut, M. Copeland Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611,

More information

Astronomical Techniques

Astronomical Techniques Astronomical Techniques Spectrographs & Spectroscopy Spectroscopy What is spectroscopy? A little history. What can we learn from spectroscopy? Play with simple spectrographs. Basic optics of a spectrograph.

More information

Open Cluster Research Project

Open Cluster Research Project Open Cluster Research Project I. Introduction The observational data indicate that all stars form in clusters. In a cloud of hydrogen gas, laced with helium and a trace of other elements, something triggers

More information

Universe. Chapter 6. Optics and Telescopes 11/16/2014. By reading this chapter, you will learn. Tenth Edition

Universe. Chapter 6. Optics and Telescopes 11/16/2014. By reading this chapter, you will learn. Tenth Edition Roger Freedman Robert Geller William Kaufmann III Universe Tenth Edition Chapter 6 Optics and Telescopes By reading this chapter, you will learn 6 1 How a refracting telescope uses a lens to form an image

More information

Hubble Science Briefing: 25 Years of Seeing Stars with the Hubble Space Telescope. March 5, 2015 Dr. Rachel Osten Dr. Alex Fullerton Dr.

Hubble Science Briefing: 25 Years of Seeing Stars with the Hubble Space Telescope. March 5, 2015 Dr. Rachel Osten Dr. Alex Fullerton Dr. Hubble Science Briefing: 25 Years of Seeing Stars with the Hubble Space Telescope March 5, 2015 Dr. Rachel Osten Dr. Alex Fullerton Dr. Jay Anderson Hubble s Insight into the Lives of Stars Comes From:

More information

IceCube: Ultra-high Energy Neutrinos

IceCube: Ultra-high Energy Neutrinos IceCube: Ultra-high Energy Neutrinos Aya Ishihara JSPS Research Fellow at Chiba University for the IceCube collaboration Neutrino2012 at Kyoto June 8 th 2012 1 Ultra-high Energy Neutrinos: PeV and above

More information

Let us consider a typical Michelson interferometer, where a broadband source is used for illumination (Fig. 1a).

Let us consider a typical Michelson interferometer, where a broadband source is used for illumination (Fig. 1a). 7.1. Low-Coherence Interferometry (LCI) Let us consider a typical Michelson interferometer, where a broadband source is used for illumination (Fig. 1a). The light is split by the beam splitter (BS) and

More information

Scintillation Detectors

Scintillation Detectors Scintillation Detectors J.L. Tain Jose.Luis.Tain@ific.uv.es http://ific.uv.es/gamma/ Instituto de Física Corpuscular C.S.I.C - Univ. Valencia Scintillation detector: SCINTILLATION MATERIAL LIGHT-GUIDE

More information

Modern Image Processing Techniques in Astronomical Sky Surveys

Modern Image Processing Techniques in Astronomical Sky Surveys Modern Image Processing Techniques in Astronomical Sky Surveys Items of the PhD thesis József Varga Astronomy MSc Eötvös Loránd University, Faculty of Science PhD School of Physics, Programme of Particle

More information

Hunting for Asteroids. Roy A. Tucker Goodricke - Pigott Observatory. Canary Islands January 2013

Hunting for Asteroids. Roy A. Tucker Goodricke - Pigott Observatory. Canary Islands January 2013 Hunting for Asteroids Roy A. Tucker Goodricke - Pigott Observatory Canary Islands January 2013 Asteroids The first, Ceres, discovered January 1, 1801 in Palermo Sicily by Giuseppe Piazzi The Bode-Titius

More information

NEON Archive School 2006

NEON Archive School 2006 NEON Archive School 2006 Introduction to Spectroscopic Techniques (low dispersion) M. Dennefeld (IAP-Paris) Outline Basic optics of gratings and spectrographs (with emphasis on long-slit spectroscopy)

More information

Lecture 12: Distances to stars. Astronomy 111

Lecture 12: Distances to stars. Astronomy 111 Lecture 12: Distances to stars Astronomy 111 Why are distances important? Distances are necessary for estimating: Total energy released by an object (Luminosity) Masses of objects from orbital motions

More information

Telescopes. Optical Telescope Design. Reflecting Telescope

Telescopes. Optical Telescope Design. Reflecting Telescope Telescopes The science of astronomy was revolutionized after the invention of the telescope in the early 17th century Telescopes and detectors have been constantly improved over time in order to look at

More information

GRAINE project: Cosmic Gamma-ray Observation by Balloon-Borne Telescope with Nuclear Emulsion

GRAINE project: Cosmic Gamma-ray Observation by Balloon-Borne Telescope with Nuclear Emulsion Cosmic Gamma-ray Observation by Balloon-Borne Telescope with Nuclear Emulsion Shigeki Aoki 1 Kobe University Kobe 657-8501 Japan E-mail: aoki@kobe-u.ac.jp for GRAINE collaboration Kobe University, Kobe

More information

Determining the Specification of an Aperture Array for Cosmological Surveys

Determining the Specification of an Aperture Array for Cosmological Surveys Determining the Specification of an Aperture Array for Cosmological Surveys P. Alexander University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, UK. A. J. aulkner Jodrell Bank

More information

McMath-Pierce Adaptive Optics Overview. Christoph Keller National Solar Observatory, Tucson

McMath-Pierce Adaptive Optics Overview. Christoph Keller National Solar Observatory, Tucson McMath-Pierce Adaptive Optics Overview Christoph Keller National Solar Observatory, Tucson Small-Scale Structures on the Sun 1 arcsec Important astrophysical scales (pressure scale height in photosphere,

More information

Hubble s Law and the Cosmic Distance Scale

Hubble s Law and the Cosmic Distance Scale Lab 7 Hubble s Law and the Cosmic Distance Scale 7.1 Overview Exercise seven is our first extragalactic exercise, highlighting the immense scale of the Universe. It addresses the challenge of determining

More information

Cherenkov Telescope Array Status Report. Salvatore Mangano (CIEMAT) On behalf of the CTA consortium

Cherenkov Telescope Array Status Report. Salvatore Mangano (CIEMAT) On behalf of the CTA consortium Cherenkov Telescope Array Status Report Salvatore Mangano (CIEMAT) On behalf of the CTA consortium Outline Very-High-Energy Gamma-Ray Astronomy Cherenkov Telescope Array (CTA) Expected Performance of CTA

More information