User Manual

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Index

Overview

Useful information on how to effectively use the search page

Useful information on how to effectively use the result page

Other useful information about this program

Browser requirements and Privacy statement

Version history

Useful Information on using search page effectively


Instrument Parameters   Start Time  Set the earliest time for searching. The earliest available data is March 16, 1996.  Day can be specified either as Month and Day, or by Day of Year (1-366). 
Stop Time Set the latest time for searching. The latest available data is July 29, 2004.
Please note that we have restricted our result set to 27,000 records, equivalent to approximately six months of data. Longer periods can be searched, but only if you restrict your search parameters. Contact us if you need access to larger blocks of data.
Reset Time Reset to earliest and latest available mission times.
Operating Sequence UVI operations are defined by instrument sequences which define which filters will be used, what order they will be sequenced, and what the relative integration times will be.  A summary of common sequence definitions is posted below . 
Science Objective This pull down menu provides the option to search based on a science objective. Each science objective listed on the menu maps to equivalent operating sequences.
Door Position UVI is equipped with a contamination door that is closed during spacecraft maneuvers and at other times.  The door is equipped with a MgF2 window which allows viewing, but with a factor of 2 decrease in sensitivity.   Check the ignore option to search independent of door position.
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Field of view
parameters and
geophysical indices 		Latitude Latitude of the center of the UVI FOV, in degrees.  Range -90 to +90.  Coordinates can be searched on either geographic or magnetic apex coordinates.
Longitude

Longitude of the center of the UVI FOV, in degrees.  Range 0 to 360.  Coordinates can be searched on either geographic or magnetic apex coordinates. Details are posted on another page.
Distance

Distance of the Polar spacecraft from the center of the earth.  Can be specified either in kilometers or in Earth radii (6378 km).

Despun Angle Relative direction of the Polar spacecraft despun platform, in degrees.   Range from -180 to +180.  Zero degrees is defined as the nadir direction (towards earth).
Percent on Earth

Search based on the percent of the UVI field of view (FOV) on earth.  The user can either enter a range to search upon or can choose to search independent of the FOV. The default is between 75 and 100 percent.
SZA Solar Zenith Angle, in degrees.  Range from 0 (noon) to 180 (midnight).  The pulldown menu allows selection of common ranges, for example twilight.
kp Planetary K index.  Range 0 (quiet) to 9 (greatly disturbed), quasilogarithmic with fractional parts expressed in thirds of a unit.  Note that the index is a code, and cannot be manipulated by arithmetic operations. A K-value equal to 27, for example, means 2 and 2/3 or 3-; a K-value equal to 30 means 3 and 0/3 or 3 exactly; and a K-value equal to 33 means 3 and 1/3 or 3+.
ap Linear analog to kp.  Ranges 0 to 400 in units of 2 nT
Dst Equatorial disturbance storm time index.
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Solar Wind Bx, By, Bz

OMNI GSM IMF,  downloaded from the  NGDC/SPIDR data server, to whom we express our appreciation.  One minute data is interpolated to the UVI image time.  The data selection criteria for all the solar wind data, as given by SPIDR, is listed below.

"Data... are collected from all available satellites, travel time corrected, and merged by priority: ACE, ACE real-time, WIND, IMP8. Time correction is done for the solar wind arrival at the Earth surface with the velocity averaged over the observation day."

 
Velocity OMNI solar wind speed (|Vxw|) in km/s.
Ion density OMNI solar wind ion density in cm^-3.
Dynamic pressure

Pdyn=N mp v^2, where Pdyn is the dynamic pressure (nPa), N is the OMNI ion density, mp is the proton mass, and v is the OMNI solar wind speed.
Epsilon The Akasofu epsilon parameter as provided by Rick Doe (SRI International) through 7/28/02.  The original data set, at 1- to 4-minute resolution, was interpolated to the nearest UVI image time.  Details of the calculation are given below.

"This [data] presents magnetopause power index, after Burton et al., JGR v80, 4204, [1975], in Watts for the period from 01 March 1996 to 28 July 2002 (0049:32).

Epsilon represents the input solar wind power available for subsequent magnetospheric energization and is equivalent to Akasofu's Epsilon parameter (magnetopause energy flux) multiplied by an assumed magnetopause surface area of 49 square Re:

  epsilon = Vsw * |B|^2 * (sin(theta/2))^4 * (49)

where Vsw is the solar wind velocity, |B| is the IMF magnitude, and theta is IMF polar angle in the Y-Z GSE plane (atan(By/Bz)).

Epsilon has been calculated from the WIND satellite over the period from 01 Mar 1996 (0043:01) to  01 Feb 1998 (0054:22) at approximately 1-minute time resolution.  Thereafter, Epsilon has been calculated from ACE satellite data at approximately 4-minute resolution.

All measurements have been propagated from the X-GSE location of the satellite to the assumed magnetopause at 10 Re at the instantaneous X-GSE component of the solar wind velocity."
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Image-Derived
Parameters

These parameters
are not derived for
altitudes below 6 Re.

 Auroral Power (GW)

The estimated power deposited throughout the auroral oval is stored in our database and can used as a search criterion.  This information was compiled by automated, unsupervised algorithms and is subject to a number of possible errors.  Some of these include underestimates due to not seeing the full oval, large noise levels during radiation belt passage, and algorithm failures for low quality images or unusual viewing conditions. 

For this reason, the auroral power  should be viewed as parameters to refine searches only.  It is not deemed acceptable for scientific analysis.  If such an analysis is required, please contact us to discuss your needs.

(Fill values are -1)

 
Look for images with clear oval?

If this option is selected, the search engine will attempt to locate image for which clear auroral arcs/oval are present. 

IMPORTANT: This algorithm does not correct for dayglow seen in the image.  Therefore many sunlit image may be skipped if the oval is not clearly seen against the sunlit background. 

Using this option in combination with the full oval option may be overly restrictive and not return any records.

 
Look for images with full oval?

If this option is selected, the search engine will attempt to locate image for which the entire oval is present in field of view. 
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Optional Output Default output contains date, time stamp and instrument parameters.  Select the following options for additional output. Selecting these options will significantly slow down the search.
Pointing and Spacecraft
Location 		 The field of view parameters defined above will be included if this option is selected.
Geomagnetic Indices Geomagnetic conditions (Kp, Ap, Dst) will be included if set.
Solar wind Solar wind data (Bx, By, Bz, Velocity, Ion density, Dynamic pressure, and Epsilon) will be included if set.
Housekeeping Housekeeping information will be included if set.
All This option makes your job easy if you want all three options to be selected. Checking this button automatically selects all the options.
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Common UVI Sequences  
The following table lists commonly used UVI sequences and their respective filters. The time per loop is the product of time taken to complete one frame (36.8 seconds approx) and the total number of frames.
SEQ      FILTERS TIME PER LOOP     
(in minutes)		 DESCRIPTION
13 8,04 - 8,56 - 2,B 11.04 Equatorial Arcs
27 2,LL - 2,LS - 1,B 3.07 Mean energy
30 2,04 - 2,56 - 2,LL - 2,LS - 2,B    6.13 Mean energy; Neutral Composition
39 12,LL - High time resolution
LL - LBHL,   LS - LBHS,   04 - 1304,   56 - 1356,    B - Background
Link to UVI Sequence Definitions

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Ground Stations
We have included a ground search feature for the UVI-OST database in which the user can ask if a given ground station is in the UVI field of view.

Our thanks to all those who had replied to our email requesting input data for this feature. Number of users had sent a list of ground stations of their interest. We have preprocessed them and have included 167 ground stations to our search engine for the user to select from. To help you geographically locate these ground stations, we have plotted all the ground stations on the world map. Click on to the group names on the search page to view the map.

Please note that including ground stations to your query adds to the complexity of the query and it may take longer to complete the process before the results are returned.

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