Search NSSDC's Web Site
You may use special operators such as AND, OR, and NOT to narrow your search or to rule out certain items. All search terms are case sensitive - i.e., it does not matter if you enter search terms in UPPER or lower case.
Examples of Search phrases:
- To find information about Comet Shoemaker-Levy 9:
Search for Comet Shoemaker Levy
- To find information about images of Mars:
Search for mars and image
- To find information about images other than of Earth:
Search for images not earth
- To find information about the moon or lunar missions:
Search for moon or lunar
- To find information about Venus and words starting with "volcan" for volcano, volcanic, etc:
Search for volcan* and venus
To search, simply enter a query -- type the words you want to
search for in the 'search term box' above. See the list below for a full description of searching options and their effect.
The result of this search will be a list of the documents which
satisfy your search request up to a maximum of 40 documents (or a reply that indicates that NO
documents match). The list is ordered by 'relevancy rank' (highest
first), which very roughly corresponds to the number of times the
word you searched for occurred in the document versus the size of
the document.
The following is a list of all the search options available:
- Right-hand truncation (stemming) queries -- Expand Your Search
- The query 'astro*' will find documents containing the words
'astronomy' as well as 'astrophysics'. If you are not sure of the
spelling or form of the word used in the documents, use this.
- 'And' queries -- Narrow Your Search
- The query 'mars and volcano' will find the intersection of all
the documents containing the words 'mars' and 'volcano'.
The use of 'and' limits your retrieval.
- 'Or' queries -- Expand Your Search
- The query 'mars or volcano' will find the union of all the
documents containing the words 'mars' or 'volcano'.
The use of 'or' increases your retrieval.
- 'Not' queries -- Narrow Your Search
- The query 'mars not volcano' will find all the documents containing
the word 'mars', and excluding the documents containing the word
'volcano'. The use of 'not' limits your retrieval.
- Nested queries -- Complicated Searches
- The query '(mars and volcano) or viking not Mariner' will find the union of all
the documents containing the words 'mars', and 'volcano'. It will then add (union)
all documents containing the word 'viking'. Finally, it will exclude all documents
containing the word 'Mariner'.
| SEARCH | FEEDBACK | HELP |
Go to the NSSDC Home Page
The search service was developed by Jason Mathews and maintained by Ed Bell.
Nathan L. James, james@nssdca.gsfc.nasa.gov, +1-301-286-9789
Code 633, NASA Goddard Space Flight Center
Greenbelt, MD 20771, USA
Ed Bell, ed.bell@gsfc.nasa.gov, +1-301-286-1187
Code 633, NASA Goddard Space Flight Center
Greenbelt, MD 20771, USA
Last Update: February 27, 1996, GJM. NASA Official: Dr. Joseph H. King, Head, NSSDC.