# Presentation: 479535

## National Virtual Aeronomical Observatory

**National Virtual Aeronomical Observatory**

**Brian Sharpee**
**Molecular Physics Laboratory**
**SRI International**

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 1) What is the NVAO?

- away

- From 2x10    km
- away

- 16

- A “virtual observatory”, allowing the observation of the earth’s
- atmosphere with astronomical instrumentation without
- physically traveling to an observatory.
- A catalog of sky spectra taken with astronomical instrumentation
- from numerous telescopes.
- An interactive interface to directly derive scientific
- information from cataloged spectra.

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 2) Why does the atmosphere glow at night?

- From 85 km
- away

- From 2x10    km
- away

- 16

*Planetary Nebula: IC 418*

*Reduced spectrum of IC 418 in vicinity of neutral oxygen "green**”** line at 557.7 nm*

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 2) Why does the atmosphere glow at night?

-   During day: sunlight disassocaites
-   molcules and ionizes atoms.

- O

- O

- O2

- O+ ,NO+

- O, N2

- O2, OH

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 2) Why does the atmosphere glow at night?

-    At night ions, atoms, molecules
-    recombine:

-    O + O + N2/CO2     N2/CO2 + O2*
-    O2* + O      O2 + O(1S)
-    O3 + H      O2 + OH(v=1-9)
-    NO+ + e-      O +N(2D)
-    O2+ + e-      O + O(1D, 1S)

- O

- O

- O2*

- N2

- N2

- O+ ,NO+

- O, N2

- O2, OH

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 2) Why does the atmosphere glow at night?

- OH*     OH(v>=0)+h(480-3000 nm)
- O2*      O2/O2* + h(260-1270 nm)
- O(1S)     O(1D) + h(557.7 nm)
- Na(2P)      Na + h(589.0,589.6 nm)
- O(1D)      O+ h(630.0,636.0 nm)
- N(2D)      N+h(519.8,520.0 nm)

- Excited atoms and molecules
- quenched or radiate:

- O+ ,NO+

- O, N2

- O2, OH

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 3) Why study the nightglow?

- away

- From 2x10    km
- away

- 16

- Provides information on the chemistry, kinetics, and
- density distributions of species producing nightglow.
-       => templates for atmospheric models
- Measurement of fundamental atomic parameters
- (wavelengths, spontaneous emission coefficients).
- Astronomical sky spectra offer high spectral resolution,
- dispersion, sensitivity, simultaneous bandwidth unavailable
- to aeronomers for the study of the nightglow.

_**Nightglow**_**: Emission from excited ions, **
**atoms, and molecules that “relax”/radiate at night**

*All-sky OH nightglow *
*emission (Taylor, Pendelton,*
* **and  Gardner,  Adv. Space *
*Res., 2001)*

- 15 papers investigating the quiet night-time atmosphere, published by
- SRI investigators using astronomical spectra of the nightglow

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design

- SRI

- Archives

- 2. Reduction
-     Software

- Database

- Toolbox

- 3. NVAO Facility/Interactive Interface

- 16

- Visualization/
- Manipulation

- Browser

*Query*

*Data*

- 1. Data Sources

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design – Data Sources

*Planetary Nebula IC 418*
*CTIO Blanco 4 meter echelle spectrum*

- nebular emission line

- nightglow emission line

- Individual high spectral orders
- at resolution ()=4000-100000
- Observed range per image
-  = 100-800 nm

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

- Echelle Spectra:

## 5) NVAO Design – Data Sources

- SRI

- Archives

_**PRESENT  NVAO DATABASE CONTENTS AND STATUS**_

- All data fully extracted and wavelength calibrated to better than 0.001 nm at 750 nm
- Small subset of ESI spectrograph data absolute flux calibrated

- HIRES

- ESI

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Data Sources

**SMOKA (Subaru) Archive: (Manua Kea, Hawaii)**
-  Telescopes: 8.2 meter, Okayama Obs. 1.88 meter
-  Instruments: Faint Object Camera (long slit), HDS (echelle), HIDES (echelle)
-     5000 spectra from medium to high resolution instrumentation.
- I**ssac Newton Group (ING) Archive: (La Palma, Canary Islands)**
-  Telescopes: William Herschel 4.2 meter, Issac Newton 2.5 meter
-  Instruments: OASIS, ISIS (long-slit/echellette), UES (echelle)
-      Significant fraction of 430,000 total observations are spectra.
**European Southern Observatory (ESO) Archive: (La Silla, Paranal, Chile)**
-   Telescopes: VLT 4 x 8.2 meter, NTT 3.5 meter, 3.6 meter, 2.2 meter
-   Instruments: FEROS (fiber echelle), UVES (fiber echelle), CES (fiber echelle)

_**SPECTRA ARCHIVES**_

-    Archives under development for **GEMINI North and South **(Mauna Kea, Chile)
-    **Keck Observatory** (Mauna Kea),  **HET/McDonald Observatory** (Texas)

- SRI

- Archives

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Reduction Software

- as recorded from CCD
- No real time transfer of spectra from archives
-  available
- Associated spectra for calibration also stored as
-  raw files

-  *instrumental signature removal, detector biases and individual *
* **pixel responses determination, correction for CCD defects*

*wavelength calibration, absolute intensity calibration*

- 2. Reduction
-     Software

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Reduction Software

- 2. Reduction
-     Software

- “Pipeline” (Mostly Automated) Calibration:

- Keck/HIRES and ESI:

- MAKEE (T. Barlow)

- VLT/UVES:  Built into MIDAS (ESO)

*Full reduction and calibration to wavelength determination*

*Full reduction to intensity calibration*

- Manual Reduction and Calibration:

- Image Reduction and Analysis Facility (IRAF):
- National Optical Astronomical Observatories (NOAO)

- Custom written Perl and Fortran code
- using CFITSIO code (NASA Goddard – HEASARC)

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- Database

- Attributes of sky spectra stored in
- MySQL database upon completion
- of their reduction and calibration
- Computes and sorts attributes by
- common aeronomic and astronomic

*Dst/Kp indices, shadow height, solar depression angle,*
*right ascension, declination, moon brightness*

- Browser

- Perl/CGI web form for forming a
- query to select spectra based upon
- common aeronomic and astronomic
- parameters:

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- Toolbox

- Visualization/
- Manipulation

- Tools that operate on spectra selected from database
- by browser query: (written in Perl)
-      => Peak detection, line profile fitting, intensity measurement
-      => Line measurement collation by aeronomical parameter
-      => Calculation of physical parameters from collections
-            of line detections and measurements

*i.e. mesopausal temperature*

- Manipulation of output data products from
-  toolbox: (output spectra, line intensity
-  measurements vs. physical parameters) for
-  plotting or interactive measurement on-line

- (written in Perl, using PGPLOT)

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- NVAO will make available this spectra to the whole aeronomy/astronomy communities

- Build a _Virtual Observatory_: suite of analysis tools that allow users to
- perform "experiments" or ask "questions" of the data:
-   => How do multiple mesopausal temperatures compare with time
-         of night?
-   => What trends exist between two features with time of night/season/
-         geographic location?
-   =>  What else was going on when I was measuring a particular
-         atmospheric parameter with another instrument (such as Na
-         LIDAR)?
- Emphasize easy accesibility via interactive web tools: immediate
- “science” with minimal user effort (isolate reduction/ calibration details)

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- Browser

- Database

- Toolbox

- “Return a spectrum showing N(2D-4S) 519.8 nm on June 3, 2000
-  at any time between UT 8-10 at Mauna Kea, HI (Keck)”

*Query:*

- ASCII file
- (intensity vs. wavelength)

*Data:*

- _Sample Query #1_:

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- Browser

- Database

- Toolbox

- “Return a spectrum showing N(2D-4S) 519.8 nm on June 3, 2000
-  at any time between UT 8-10 at Mauna Kea, HI (Keck)
-  for interactive measurement”

*Query:*

- _Sample Query #2_:

- Visualization/
- Manipulation

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Design: Interactive Interface

- Browser

- Database

- Toolbox

- “Plot the mesospheric temperature from v=9 OH Meinel band system lines
-   over all nights 21-25 October 2000 from Mauna Kea, Hawaii (Keck)”.

*Query:*

- _Sample Query #3_:

- Visualization/
- Manipulation

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Status

-  VLT/UVES, HET/HRS

- Acquired and adapting VLT/UVES pipeline for
- additional instruments

- Completed

- Basic tools (line detection/measurement) completed, some
- more advanced tools (temperature determination) also completed

- Simple interface for interacting
- with database/downloading
- ASCII spectrum files completed.

- Written

- Database

- Toolbox

- Visualization/
- Manipulation

- Browser

- Data Sources

- Reduction Software

- NASA AISRP Meeting
- NASA Ames, April 6, 2005

## 5) NVAO Immediate/Long-Term Plans

-     on-line for downloading reduced spectra
- 2) Adapt pipelines (MAKEE and UVES) for
-     use with potential archival spectrum sources
- 3) Translate display/data manipulation tools written
-      in Perl to Javascript for incorporation into web
-      interface
- 4) Develop more sophisticated query language
-     and associated browser/database interface to
-     allow more elaborate queries for science derivation

- NASA AISRP Meeting
- NASA Ames, April 6, 2005