In general, the copyright to a work of art belongs to the creator of the work. In the case of astrophotography, the astrophotographer is the creator of the work, so they own the copyright.

The fair use doctrine is a legal principle that allows limited use of copyrighted material without permission from the copyright holder. This doctrine is based on the idea that certain uses of copyrighted material, such as criticism, comment, news reporting, teaching, scholarship, or research, do not harm the copyright holder's interests and should be allowed.

When determining whether a use of copyrighted material is fair use, courts consider four factors: the purpose and character of the use, the nature of the copyrighted work, the amount and substantiality of the portion used, and the effect of the use on the potential market for the copyrighted work.

The term of copyright protection for astrophotographs is the life of the astrophotographer plus 70 years. This means that the copyright to an astrophotograph lasts for the entire life of the astrophotographer and for 70 years after their death.

To register a copyright for an astrophotograph, you must file an application with the U.S. Copyright Office. The application must include a copy of the astrophotograph, a filing fee, and a completed application form.

Registering a copyright for an astrophotograph provides public notice of your copyright claim, makes it easier to enforce your copyright if it is infringed, and allows you to sue for damages if your copyright is infringed.

A copyright protects original works of authorship, while a trademark protects distinctive signs used in commerce. A copyright protects works of art, while a trademark protects words, phrases, symbols, or designs used to identify a product or service. A copyright protects works that are fixed in a tangible medium, while a trademark protects works that are used in commerce.

A copyright protects original works of authorship, while a patent protects new and useful inventions. A copyright protects works of art, while a patent protects processes, machines, and compositions of matter. A copyright protects works that are fixed in a tangible medium, while a patent protects works that are used in commerce.

A copyright protects original works of authorship, while a trade secret protects confidential information. A copyright protects works of art, while a trade secret protects formulas, patterns, and processes. A copyright protects works that are fixed in a tangible medium, while a trade secret protects works that are used in commerce.

A copyright protects original works of authorship, while a design patent protects the ornamental design of a functional item. A copyright protects works of art, while a design patent protects the appearance of a product. A copyright protects works that are fixed in a tangible medium, while a design patent protects works that are used in commerce.

A copyright protects original works of authorship, while a plant patent protects new and distinct varieties of plants. A copyright protects works of art, while a plant patent protects plants that are reproduced asexually. A copyright protects works that are fixed in a tangible medium, while a plant patent protects works that are used in commerce.

A copyright protects original works of authorship, while a mask work protects the layout of a semiconductor chip. A copyright protects works of art, while a mask work protects the design of a semiconductor chip. A copyright protects works that are fixed in a tangible medium, while a mask work protects works that are used in commerce.

A copyright protects original works of authorship, while a sui generis right protects unique forms of expression. A copyright protects works of art, while a sui generis right protects works that are not covered by other forms of intellectual property protection. A copyright protects works that are fixed in a tangible medium, while a sui generis right protects works that are used in commerce.

A copyright protects the economic rights of the author, while a moral right protects the author's personal rights. A copyright protects the right to reproduce, distribute, and sell a work, while a moral right protects the right to claim authorship of a work. A copyright protects the right to make derivative works, while a moral right protects the right to prevent the distortion or mutilation of a work.

The limitations on the copyright owner's exclusive rights include fair use, first sale, and limitations on the duration of copyright.