# Presentation: 517922

## Virtual Astronomy

- Robert J. Brunner
- PDQ Initial Meeting
- Department of Astronomy, University of Illinois
- NCSA Research Scientist
- October 1, 2002

## Overview

- What is the Data?
- What is Virtual Astronomy?
- What Exactly do I want to do?
- Virtual Subject needs Real Requirements – Help.

## It’s a Big Sky!

**	****	****	****(Present Situation)**
**40,000 sq. degrees = 2 trillion pixels**
**One band:     ****	****         ****	****4 Terabytes**
**Multi-wavelength: ****	****100’s Terabytes**
**Time dimension:  ****	****     ****	****Petabytes**

**It’s a Big Sky!**

## Imaging Data

## Catalog Information

## Spectral Data

## Numerical Simulation

## Multiwavelength Milky Way

## Multiwavelength Crab Nebulae

**X-ray, optical, infrared, and radio views of the nearby Crab Nebula, which is now in a state of chaotic expansion after a supernova explosion first sighted in 1054 A.D. by Chinese Astronomers.**

## The Challenge

**Size of the archived data **
- (Present Situation)
**40,000 square degrees **
**= 2 trillion pixels**
**One band:     ****	****   ****4 Terabytes**
**Multi-wavelength: ****100’s Terabytes**
**Time dimension:   ****Petabytes**
***Training the next generation***

## Scientific Opportunities

**Discovering Rare & Exotic Objects**
**High Redshift Quasars**
**Statistical Astronomy**
**Galactic Structure**
**Large-Scale Structure**
**Multi-Wavelength Image Analysis**
**Multi-Wavelength Morphology**
**Correlate Diffuse Emission**
**Temporal Variability**
**Gravitational Micro-Lensing**
**Supernovae**
**Near-Earth Asteroids**

## Digital Universe

**Virtual Astronomy Paradigm:**
**Virtual Observatories**** ****are**** ****portals**** ****into ****	****	****“*****Digital Universe*****” (Archives)**
**Virtual Telescopes**** ****are software and hardware technologies that**** ****gather**** ****the data**
**Virtual Instruments**** ****are software technologies that**** ****process**** ****data**

## VO: Conceptual Architecture

- User Interface

- Data

- Data

- Data

- Data

- Data

-   Astronomer

## VO: Conceptual Architecture

- User Interface

- Data

- Data

- Data

- Data

- Data

-   Astronomer

**There are 125,852 galaxies which satisfy these criteria. What now?**

## Catalog Interface

**SELECT  obj.field.segment.run,          // or whatever you want**
**        ****obj.field.segment.camCol,**
**        ****obj.field.segment.rerun,**
**        ****obj.field.field,**
**        ****obj.objID, obj.ra, obj.dec**
**FROM galaxy                             // select galaxy and primary only**
**WHERE (**
**   ****flag1 & (AR_DFLAG1_BINNED1 | AR_DFLAG1_BINNED2 | AR_DFLAG1_BINNED4) > 0 **
**&&**
**   ****flag1 & (AR_DFLAG1_BLENDED | AR_DFLAG1_NODEBLEND | AR_DFLAG1_CHILD) != AR_DFLAG1_BLENDED **
**&& **
**   ****obj.petroCounts[3] < 23**
**)**
**// Notes: AR_DFLAG -> AR_DFLAG1 or OBJECT1**
**// petrocounts -> petroCounts[3] (i is 4th in array[0:4] of u,g,r,i,z)**
**// Selecting Galaxy (or galaxy) class already ensures it is a primary object because Galaxy is a subclass of Primary.**
**// The petroCounts is a member of the PhotoObj class, which is accessed**
**// via the "photoobj" (alias "obj") association link in the tag class.**

## Exploring Parameter Space

***Given an arbitrary parameter space:***
- Data Clusters
- Points between Data Clusters
- Isolated Data Clusters
- Isolated Data Groups
- Holes in Data Clusters
- Isolated Points

## Exploring Parameter Space

**  **

## Mining Type 2 Quasars

- Where are the high redshift Type 2 Quasars?
- Current surveys are biased against finding them, even though they should be at least as numerous Type 1 quasars from purely geometric arguments.

- Only a *multi-wavelength* approach can provide the unbiased sample which can test the theories of  AGN Unification

## Mining BAL Quasars

**“****Extreme” Broad Absorption Line Quasars are another class of color space outliers. We can now target them, and quantify their distribution.**

## High Redshift Quasars

## Image/Catalog Correlation

- Large-Scale, Image/Catalog (Anti-)Correlation

## New Neighbor

**Finding new galaxies by spatial clustering of red objects**
**New galaxy is about 30 million light years away**
**Clearly visible in the 2MASS infrared image**
**Expect to find 1000’s of such galaxies with 2MASS**

**Infrared**

**Optical**

## LSB  Galaxies

- Background Enhancement Technique demonstrated on two known local group dwarf Spheroidal galaxies

## Finding New GC’s

**Finding New GC’s**

***Download Relevant 2MASS Images***

***Mosaic Requisite Infrared Images***

***8.5’ x 17’***

## Dwarf Galaxies in Nearby Groups

- Mosaic large areas to map galaxy distribution in nearby galaxy groups

## Finding Volcanoes on Venus

**JPL Adaptive Recognition Tool (JARTool)**

## Diamond Eye

**Identification and Cataloging of Geological Features for Scientific Analysis.**

## PDQ Interface

**Data Archiving (Terabytes/Petabytes)**
**Data Accessing/Mining (Teraflops)**
**Service Accessing (OGSA)**
**Data/Service Integration (Teragrid)**
**Virtual Data Creation/Persistence/Access**