If you mean "demonstrations" as in http://demonstrations.wolfram.com/search.html?query=Astronomy ,
it would be good to ask the Demonstrations site people, via the "give feedback" link in the lower-right
corner of the page, before doing much copying.
If you want to make demonstrations available on another web page, copy the link to the new page, not the whole demonstration.
See http://demonstrations.wolfram.com/about.html#Using_the_Site , the sections
- Can I reproduce material from the site elsewhere? and
- How do I embed a Demonstration on my website or blog?
