What is MIME type "application/x-wtml"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

application/x-wtml is a MIME type for files used in the WorldWide Telescope application. It works with a specialized markup language that organizes astronomical data. The files tell the software which images, objects, and links to display. They use a text-based format to arrange data in a way that the telescope software can read and render views of the cosmos.

Main use case: Enables the WorldWide Telescope to load and display collections of astronomical data.
Data linking: Connects various images, metadata, and resources into one coherent collection.
Metadata support: Holds descriptions and properties for stars, galaxies, and other celestial objects.

Files using this MIME type have the extension WTML. The x- prefix indicates a non-standard type reserved for vendor-specific or experimental use.

For further details on file formats and extensions, visit Filext.

Associated file extensions

.wtml

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: application/x-wtml

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="application/x-wtml">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'application/x-wtml');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.wtml

FAQs

What is the primary purpose of the application/x-wtml MIME type?

The application/x-wtml MIME type is used to serve WorldWide Telescope Markup Language (WTML) files. These files are XML-based collections that define how astronomical images, data, and tours are organized and displayed within the WorldWide Telescope software.

How do I configure Apache to serve .wtml files correctly?

To ensure your Apache server delivers the correct headers for WorldWide Telescope files, add the following line to your .htaccess file or main configuration: AddType application/x-wtml .wtml. This prevents browsers and the WWT client from misinterpreting the file as generic XML.

How do I add support for application/x-wtml in Nginx?

For Nginx servers, you should modify your mime.types file or the types block within your server configuration. Add the line application/x-wtml wtml; to ensure the server associates the extension with the correct MIME type.

Why does the MIME type start with "x-"?

The x- prefix in application/x-wtml indicates that it is a non-standard or vendor-specific media type. It is not part of the standard IANA registry and is used specifically for the WorldWide Telescope ecosystem.

Can I simply use text/xml instead of application/x-wtml?

While .wtml files are technically valid XML, it is recommended to use the specific application/x-wtml type. The WorldWide Telescope client may rely on this specific Content-Type header to trigger the correct parsing logic, whereas generic text/xml might be treated as raw data.

Will web browsers display application/x-wtml files automatically?

No, standard web browsers do not have built-in rendering engines for WTML content. If you navigate directly to a file with this MIME type, the browser will likely display the raw XML code or prompt you to download the file. You need the WorldWide Telescope web client or desktop app to view the visualization.

How do I troubleshoot if my WTML collection isn't loading?

First, verify that the server is returning the application/x-wtml header using browser developer tools. Additionally, because these files often reference external images, ensure that CORS (Cross-Origin Resource Sharing) headers are correctly configured if your data resides on a different domain.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.