I have seen many editorial photos of military jets taken from other airplanes and wonder where people get those from and then sell in microstock. Likewise with pictures from space that would probably be from NASA or other space-agency? Do you have to get permission? Where do they come from?

Thanks!

Don't know about jets, but regarding pictures from space Shutterstock allows to include* photos from Nasa in your design (strangely enough, since they do not accept any other public domain images besides Nasa).

*include, not resell as is

Ahoy! All NASA images are in the public domain. The reasoning is that it's a publicly funded organization, so the public should have unrestricted access to that content. The only stipulations are that you can't use the NASA logo or any people in the images for commercial use. They would be editorial only.

So you can use NASA elements as composting assets, as part of a new composition that you sell as stock... you can even sell images and footage 'as is'. I saw an interview with the head of NASA's media content and he specifically stated that there was nothing wrong with selling NASA content on stock sites,  even if it is content that people could source themselves for free.

Not sure about jets (I'm still working on jetstockfootage), but there you have it!

more info from wikipedia:

Like most images produced by the United States Government, the insignia, the "worm" logo and the NASA seal are in the public domain. However, their usage is restricted under Code of Federal Regulations 14 CFR 1221

https://en.wikipedia.org/wiki/NASA_insignia

Whoever fraudulently or wrongfully affixes or impresses the seal of any department or agency of the United States, to or upon any certificate, instrument, commission, document, or paper or with knowledge of its fraudulent character, with wrongful or fraudulent intent,

The seal restriction (and any government seal) is only restricted for use if the intent is wrongful or fraudulent. That means that selling stock photos of the seal is most likely legal (as shown by the SONY BETAMAX Supreme Court case). The restriction is primarily in regards to conterfeiting or falsifying documents.

That's probably true, but I don't think any sites have a 'fair use' category for images and footage.