To get to the ASC home page, first start mosaic by typing the xmosaic command. When the Mosaic window comes up, click on the Open button at the bottom center. A small window will come up with a place for you to enter the URL of the page you want to look at. If this space is not blank, click on the Clear button. Once the space is blank, enter the following URL:
After a few seconds, you should see a page like that in Figure 13. Use the scroll bars to move down a few inches, and you'll see some blue, underlined text (Fig. 14). These are hypertext links. Clicking on these will move you to another page. For example, clicking on ASCinfo will send you to an ASC bulletin board service (see ``ASCinfo: An ASC Information System'' in Issue 1 of this Newsletter). Remember that you can always return using the Back button.
The ASC home page is organized in sections beginning with information specifically about AXAF and the ASC, and ending with general information about the Web and Internet. The first section (Fig. 14) contains links to information about the Smithsonian Astrophysical Observatory (SAO, where the ASC is located), the AXAF spacecraft, and the latest news from the ASC. Directly under this is a selection of information available to the general public about the ASC and its activities (ASC resources).
Click on ASCinfo (or on Hypertext interface) and after a few seconds you should see the page in Figure 15. (The globe in the upper right of the Mosaic window rotates when Mosaic is busy reading information. Mosaic also gives you a running total of the number of bytes read just above the buttons at the bottom of the window.) Then click on The Advanced X-ray Astrophysics Facility: A General Description to see an article that describes the spacecraft and its capabilities. Scattered throughout the article are more links, some to information that augments the article (like Table 1 and Table 2), some to pictures that illustrate the article (like Tycho's remnant and Cygnus Loop), and some to other organizations with pages on the Web (Goddard Space Flight Center). This simple example should give you an idea how powerful Mosaic/WWW can be in disseminating and presenting related information.
The next section of the ASC home page contains links to SAO Resources, including the SAO ftp sites (Fig. 16). It is possible to retrieve files through ftp by using Mosaic. Just click on the appropriate links. For instance, click on SAOimage and you will see a list of files that you can retrieve just by clicking on them. These files allow you to build and install the SAOimage display tool. Clicking on the two README files will give you information on how to install SAOimage, and clicking on any of the binaries will cause the binary to be downloaded to your site. In addition, clicking on a directory will cause you to move into that directory, so you can navigate around the ftp site looking for what you need.
Figure 13. ASC Home Page (top) as of Summer 1994
Figure 14. ASC Home Page (ASC resources) as of Summer 1994
Figure 15. ASC Bulletin Board (ASCinfo) as of Summer 1994
Figure 16. ASC Home Page (SAO resources) as of Summer 1994
Figure 17. ASC Home Page (bottom) as of Summer 1994
A number of institutions have assembled lists of resources of interest to astronomers on the Web. The next section of the ASC home page contains links to the three most comprehensive lists (Fig. 16), maintained by the European Southern Observatory, the Space Telescope Science Institute, and the National Radio Astronomy Observatory.
The bottom of the ASC page (Fig. 17) has a link to a mini-tutorial that will give you more information about how to move about the Web with Mosaic. You can get to the tutorial by clicking on Click Here. This tutorial also has links to a more comprehensive tutorial and to a demo document that demonstrates the audio-visual features of Mosaic.
The last things on the ASC home page are links to the larger WWW environment. Clicking on the link to internet resources for instance will give you an idea of the huge amount of information available in just about any subject imaginable.
The contents of the ASC Home Page will evolve, and we anticipate that it will be a major route to user information about AXAF.