NVO and The Digital Planetarium NVO Outreach Workshop July 11, 2002 Ed Lantz Product Development manager Spitz, Inc.

Large-Format Film Theatre Traditional Planetarium Digital Planetarium Dome Theaters

Hemispheric Projection Screen Starfield Projector High-resolution astronomical simulation Hemispheric Slide Projection or All Skys Narrow Field Video is Common Laser Graphics - Full or Partial Dome Combination Large-Format Film, Planetarium Total Annual Attendance Worldwide: 87,400,000 Traditional Planetaria

Planetarium Worldwide % of Classification # of Theaters Total School/District 99936% University/College 39714% Museum/Science Center 37514% Observatory/Other201 7% Unclassified78228% TOTAL 2754 Planetarium Facts * Courtesy The LNP Planetarium Compendium, Loch Ness Productions, 2000

Dome Size (m) # of Theaters # Tilted Domes Portable 774 Planetarium Facts * Courtesy The LNP Planetarium Compendium, Loch Ness Productions, 2000

Hemispheric Projection Screen Tilted 20-30º typically Large-Format Film 15-perf, 70mm (original IMAX® format) 8-perf, 70mm (increasingly popular format) Dome Diameters from 15m to 28m+ 254 LF Theaters Worldwide - Half are Domes* 175 Large-Format Films Released* Large-Format Film Theater * From White Oak Associates, Inc. Inventory of Large Format Theaters, 1998 edition

Full Dome or Partial Dome Video Projection Multiple Edge-Blended Projectors or Fisheye CRT, DLP, LCoS projector technologies 30+ Existing/Planned Theaters by 7 Manufacturers Most Use Pre-Rendered, Pre-Recorded Shows Hi-res digital video graphics technologies Realtime 3D Interactive Becoming Affordable Digital Planetarium

Evans & Sutherland - Salt Lake City, UT GOTO Optical - Japan Spitz, Inc. - Chadds Ford, PA Sky-Skan - Nashua, NH Trimension, Inc. - Burgess Hill, UK Silicon Graphics/Zeiss/Schneider Minolta - Japan Digital Dome Manufacturers

AMNH/Rose Center - New York City Bibliotheca Alexandria - Alexandria, Egypt Burke Baker Planetarium - Houston, Texas Exploration Place - Wichita, Kansas National Space Centre - Leicester, UK LodeStar Planetarium - Albuquerque, NM Northern Lights Centre - Watson Lake, Yukon National Air and Space Museum - DC Adler Planetarium - Chicago Sampling of Digital Planetaria

LodeStar Planetarium Albuquerque, NM Bibliotheca Alexandria Alexandria, Egypt

Spherical Projection Formats Single Projector (Fisheye) Edge-Blended Projectors

Edge-Blended Projection Polar Source is Split Into Sub- Frames and Edge- Blended Sub Frame 1 Sub Frame 2 Sub Frame 3 Sub Frame 4

Fisheye Projection Polar Fisheye Source Image Simple Configuration Limited Hemispheric Resolution (2048x1536 pixels) Requires Projector Inside Theater Space

Astronomical Visualization Night sky visualization –Naked eye and deep sky 3D visualization and simulation –Astrophysical models –Digital Galaxy, Cosmic Atlas, Deep Space Explorer, etc. Informal Educational Programming Need compelling, meaningful stories –What is our place in the universe? –Whats out there? –What does it all mean? »My future, mankinds future Data queries & data interpretation Visualization data mining, formatting Feeding the Digital Planetarium

Public Planetaria Science & astronomy educators Media/production staff Astronomers School Planetaria Science and astronomy educators Show Producers Writers Art directors Animators Editors Musicians Who Are We?

Pre-Rendered Shows Dome master format Composited Images –All-Sky Images –Deep-Sky Objects Realtime 3D Texture maps Star/Object Data Graphics Formats

Pre-Rendered Shows Dome Master Formats Spherical mapping format Master format for archiving, distribution, etc. Independent of particular projection geometry Defined only by resolution, field-of-view, file type –independent of specific projection scheme

Polar Fisheye Master 180º 0º -90º Longitude +90º 0º +90º -90º Polar Fisheye (Azimuthal Equidistant)

Equidistant Cylindrical Master -180º +180º 0º -90º Longitude Latitude 0º +90º Equidistant Cylindrical

Skinning a Sphere with Platonic Solids

Cubic Master Advantage - Efficient File Format Disadvantage - Scene is Broken Up, Difficult to Preview

All-Sky Images Celestial sphere at all available wavelengths –specified coordinate system –compositing must be seamless, no missing data Numerous mappings acceptable –azimuthal equidistant (separate hemispheres) –equidistant cylindrical –Hammer-Aitoff –cubic Deep-Sky Objects Need sufficient metadata! Vis Needs: Pre-Rendered Shows

All-Sky Image Resolution Number of Pixels Required to Project Eye-Limited Resolution on Hemisphere: Number of Pixels = (0.5) (4 steradians) (57.3°/steradian) 2 (60 arc min/deg) 2 (0.5 arc min/pixel) 2 = 300 Million Pixels!!!

Fisheye Projection Systems 1024x1024 or 1536x1536 polar frame Edge-Blended Projection Systems up to 4000x4000 polar frame Highest Resolution All-Sky Images in Use 14,000x7200 equidistant cylindrical (3 arcmin) Nearly 300 MB file! Seamless Transition to High-Magnification Images Deep sky zoom with higher resolution All-Sky Image Resolution

Many Excellent Images Available from STScI/Aura Where Do They Go in the Night Sky??? Need Metadata! Image angular height/width Image center RA/Dec Image rotation w.r.t. celestial coordinates Image brightness/magnitude? Estimated object distance (for 3D systems) Simplified Search Capability a Plus Deep Sky Objects

Deep Sky Zoom

Higher Resolutions allow Seamless Zooms 1024x1024 useful 4000x4000 better 8000x8000 best! Deep Sky Object Resolution

Numerous Formats in Use TARGA is currently most popular format Compression artifacts can be a problem High Dynamic Range Formats Needed Display dynamic range limited (1000:1) HDRI, Cineon, others… Image Formats

Automated Downloads Solar weather Solar system images, data Transient phenomena Current terrestrial/space based images & metadata Edu releases – current event items Connecting People & Resources Not all data is accessible online Queries can actually drive future research Amateur astronomer image exchange Astronomers have stories to tell… we need stories Other Ideas…

Thanks...