This page describes how to use the ST Press Release Search form and describes the individual fields in the form. Use the form to locate and retrieve observations from HST press releases. All data is public and may be retrieved through this interface.
The search script will perform a database search for each extracted Data ID, target, or set of coordinates, contained in the uploaded list. Target names will be resolved to coordinates. If a resolver error occurs with target names, the search will abort and the compiled results displayed. Coordinates may be given in several formats including sexigesimal and decimal degrees. If the output is requested in CSV or Excel spreadsheet format, a blank line will be used to distinguish the results of one target search from another. VOTable format incorporates separate RESOURCE tags for each database query.
Use the other form entries to specify field delimiters,
RA, DEC, or Target column numbers (when the file contains a table
of values), and file contents (target names or coordinates).
The browse button allows users to seach local directories to
locate files.
Warning: Since uploading long lists can take a while to run,
uploaded files are limited to 10,000 entries.
Note that each target, or set of coordinates specified in the uploaded file, is treated as a separate query. The results are displayed as each query is run. If however Data ID's are entered (up to 10,000 are allowed), it is processed as a single query (e.g., select * where data_id in (did1,did2,...).
To avoid displaying column names after each target name or coordinate query, consider using the comma-separated values output format. Also keep in mind that not all target names are resolvable. For example, SIMBAD currently does not reolve most 2MASS IDs.
The Target Name is used in combination with the Resolver Field. If the SIMBAD, CFA (SIMBAD at CfA), NED (default) or HLA name resolver options are chosen, then coordinates returned from these services are used to perform a cone search with the specified search radius.
For most mission searches, you do NOT have to use the resolver. Choose the "Don't resolve" option to perform string searches on the object name in the database. Note Kepler catalogs do not include a generic object name field, so this option is not available for Kepler users.
When you search on the object name in the database (i.e. without using the name resolver), case will be ignored. The object name will not be wildcarded at the front and back automatically (that's so if you innocently enter IO, you don't match things like ORION). You can however wildcard the object name using * (for example, *IO*). You can also enter a comma-separated list; for example, *JUP*,*SAT* would match object names containing either JUP or SAT.
Note that most missions store some target names in a format that is not compatible with the NED or SIMBAD name resolvers. For example, most 2MASS IDs are currently not resolveable by SIMBAD.
The two main name resolver services are SIMBAD and NED. NED is the NASA Extragalactic Database at Caltech in Pasadena, California, and SIMBAD is the Set of Identifications, Measurements, and Bibliography for Astronomical Data at the Centre de Données astronomiques in Strasbourg, France (SIMBAD at CDS). A mirror site at the Center for Astrophysics in Boston is also now available and is denoted as "SIMBAD at CFA". NED is an extragalactic database, and generally won't resolve object names within the Milky Way galaxy.
Because we occasionally have problems with network connections and web servers, we now store previously resolved target names and coordinates in our own local database and search this database before trying to access the other name resolvers using various web services. By default, If no entry is found in the local cache, the entered object names will first be sent to the NED service, and, if still not found, then CFA, CDS, and HLA in that order. You may also go directly to CFA, CDS, or HLA by changing the selected name resolver, although the local cache is always checked first.
If any error occurs, the search form will be redrawn with an error message at the top. Otherwise, the returned coordinates will then be used to search the database, along with whatever other query qualifications you have given.
We recommend that you use object name resolution to find observations of specific stationary targets. This is the most reliable way to look up observations, because the observer could have given any object name at all (for example, NGC1976 instead of M42, or PARALLEL-FIELD).
The SIMBAD and NED name resolvers can resolve only fixed objects; they cannot compute the positions of moving objects (planets, comets, etc.). To find moving objects, try selecting the appropriate category option available on most MAST search forms, or as mentioned above, enter an object name that could match what you're looking for, and select "Don't resolve" for the name resolver. Note wild cards are allowed, so for Jupiter you might enter "*JUP*".
Note the examples listed below (and elsewhere) are only intended to show the format of the form entries. There is no guarantee that entering these specific values will return any search results.
You may also enter ranges of right ascension or declination, using the ".." operator. For example, you can enter 21h 51m .. 21h 52m for the right ascension, and 28 51 .. 29 51 for the declination. Comparators can also be used, i.e. ">", ">=", "<", "<=". For example, "> 85" as a declination value will return all observations with declination larger than 85 degrees. (Note when ranges of coordinates are specified the search radius will be ignored. Also, searches on ranges can be quite time consuming.)
Coordinate values may be specified using a number of formats. Examples of valid formats include:
Decimal Degrees
185.63325 29.8959861111111
Hours, minutes and Seconds
12 22 31.98 29 53 45.55
12h22m31.98s 29d53m45.55s
12:22:31.98 +29:53:45.55
12h22'31.98" 29d53'45.55"
12h 22m 31.98s 29d 53m 45.55s
12h 22' 31.98" 29d 53' 45.55"
12h 22' 31.98" -29d 53' 45.55"
12h22'31".98 -29d53'45".55
12h22m31s.98 -29o53m45s.55
12h 22' 31".98 -29d 53' 45".55
Hours/Degrees and Minutes (no seconds)
12 22 29 53
12h22m +29d53m
12h22m 29d53m
12:22m 29:53m
12h22' 29d53'
12h 22m 29d 53m
12h 22' 29d 53'
12h 22' -29d 53'
The RA may be given in decimal degrees by indicating
a D or d after the degrees:
12d 22m 29d 53m
Spacing is not important, as long as the value is unambiguous. You can
delimit the hours/degrees, minutes, and (optional) seconds with letters,
colons, spaces, or any character that's not a digit or a decimal point.
Like target names, multiple coordinates can be entered if separated by commas.
The search routine computes the angular separation between each result dataset and the search center so this really is a circular radius. (Results are generally sorted on the angular separation by default.)
Note the precession is only applied to the input coordinates. The coordinates displayed in the search results will depend on the mission database and the selected output columns. (Note: all MAST missions include J2000 coordinates as default output columns.)
If you enter a target name and use either the SIMBAD or NED name resolver, the equinox will be set to J2000.
When specifying this date, you need to include a date and an optional time. If time is omitted then then midnight (00:00:00) is assumed. This means that a specification like "July 1 1994" will look for observations done on July 1 1994 00:00:00, not for observations done for the entire day July 1 1994. To search for observations for an entire day use the range option described below.
Note also that when entering a date with the month in numerical format, the American ordering is used; i.e., the first number is the month.
The date can have any of the following formats (the month name can be spelled out or abbreviated to three letters; case is not significant):
Jul 15 1994
Jul 1994 15
15 Jul 1994
1994 Jul 15
1994 15 Jul
7/15/1994 <--- Note order of month/day of month/year for numeric formats
7-15-1994
7.15.1994
If the day is omitted, the first day of the month is assumed. This means that a specification like "July 1994" will look for observations done on July 1 1994 00:00:00, not for observations done during July 1994. Note also that when entering a date with the month in numerical format, the American ordering is used; i.e., the first number is the month.
If a time is omitted, then midnight (00:00:00) is assumed. Otherwise, you can specify a time in any of these formats:
14:30
14:30:20
14:30:20:999
14:30:20.9
4am
4 PM
04:30:20 AM
To search for observations before a given date, use <, and for observations
after a given date, use >. For example,
> Jul 15 1994
< Jul 15 1994
You can use the .. operator to search on a range of dates:
Jul 1 1994 .. Aug 1 1995
This operator is inclusive on the first date and exclusive on the second.
Finally, you can search on a list of dates or date ranges. For example,
As an example, a Kepler user might select "E(B-V)" from the pulldown menu and
enter "< 0.5" in the "Field Descriptions" box.
NOTE only fields which are not already
included on the search form should be selected. Specifying search criteria
for a field that is listed in BOTH the form and in the User Specified field, may
cause either the query to fail or return unexpected results.
You remove output columns by highlighting the column to be removed and
then clicking on the remove button to the right of the output columns list.
You may determine the order of columns by highlighting a column and
then clicking the up or down buttons to the right of the list of
chosen output columns.
You may also add more columns to the list, either singly or all
at once. To add individual columns, select the desired
column from the pull down menu beneath the list of chosen output columns,
then click the add button. The column will be added to the bottom
of the output column list. To add all the available columns, click the
"add all" button.
Note the output column form element has its own reset button to restore
the list of output columns to the values initially displayed when the page
was drawn. The reset button at the top of the form is
used to reset the other form elements.
Clicking the "clear form" button will restore the original defaults to
all isections of the form.
One warning, the amount of memory required for a search is proportional
to the number of columns requested. For large requests, users may want to
reduce the number of output columns to the minimum required.
For each field, you can select that the rows be sorted in reverse
order on that field by selecting the reverse checkbox. For example,
you can sort the rows with the most recent observations first by selecting
Observation Date for the first sort field and selecting
the reverse checkbox next to it.
One word of caution: the selected sort field can change the search results
when the query finds more rows than are displayed ( i.e, when the number of
found rows exceeds the value of "maximum records"). For example, for a search
on a particular coordinate that finds 5,000 entries, if the search
is sorted on exposure time
and 1,001 rows are to be displayed (the default), then the 1,001
shortest exposures
from the 5,000 found entries will be displayed
which may not include the entries closest to the
desired position. (It is a good idea to always sort on "ang_sep" for target or
coordinate searches).
Note when displayed as HTML, the latest search scripts will display
100 records per page. Links to the additional pages are shown
on the results page.
This paging feature however does require javascript to be turned on.
Users should be cautioned about retrieving a large number of records
(i.e., > 10,000 - 15,000) in HTML format. This can cause memory
problems for the browser (particulrly Safari) and prevent javascript
commands from functioning. It may also cause the browser to freeze
and require restarting.
Using the output format options which download results in a file can reduce the
problem.
Another option for large requests is to use "Casjobs".
Casjobs requires requesting a user name and password, and submitting
queries in SQL, but it allows users to submit large search results and
save them online. For Kepler, the link ito Casjobs is
http://mastweb.stsci.edu/kplrcasjobs/.
For other missions, check the Search_Retrieve page in the left gutter.
When queries are submitted as a web service, the default number of rows
returned is 2,000, but any value is allowed when max_rows is specified
as a query parameter. (See the
MAST Web services page for more information.)
As an example, a IUE or FUSE user might want to create a list of unique target
names for a specific object class/category. He or she would specify the desired object
class, select only "object Class" and "target name" for the output columns,
click the "Make Rows Distinct" button, then click "Search".
Note that for some missions, columns such as RA, Dec and Magnitude were frequently defined
by the observer and often have different values for the same target.
If columns such as these are chosen as output columns, there will often
be more than one row listed per object name.
Note: If no entries are found for an entry a
"no entries found" message is written in the selected format and
the program continues.
In all cases, error conditions will cause the database search to abort.
Jul 1 1994 .. Jul 3 1994,
Dec 1 1995 .. Dec 6 1995
will search for observations done within either one of these date ranges.
Any other coordinate fields contained in the searched mission catalog will be
displayed in their original format.