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ERH 314 - Technical Communications: A Mars Mission

An introduction to the conventions of writing in the workplace.

Types of sources

In general, the sources you use in your research can be divided into a few groups depending on their author, intended audience, publication, and other factors.

  • Popular sources—These are usually informal designed for a broad audience. Think about blog posts, newspaper articles, and most magazines.
  • Scholarly sources—These are written by experts for experts, based on research, they include citations or references, and are often peer-reviewed. 
  • Primary sources—These are first-hand documentation of something like an event, research, an artwork. They are usually created at the time of the event but can also include first-hand writing like memoirs. Examples of primary sources vary by subject; for example, in the sciences, primary sources document original research and include descriptions of methodology.
  • Secondary sources—These analyze or interpret primary sources and include analyses of clinical trials (science) and criticism (humanities).
  • Tertiary sources—Use these to find your other sources. These include the library catalog and research databases as well as indexes.


Mars exploration. Artwork of astronauts examining an outcrop of sedimentary rock on a Martian dune field. Their Mars rover vehicle is in the background. Mars is a rocky desert world with no surface water. Its gravity is about one third of that on Earth. The atmosphere is mostly carbon dioxide and surface temperatures are well below freezing. Martian astronauts will have to breathe their own air supply and wear heated spacesuits.

Mars exploration, artwork. Photograph. Britannica ImageQuest. Encyclopædia Britannica, Inc., 25 May 2016. Accessed 11 Aug 2016.

Preparing for a Mission to Mars

VMI Reference Librarian

Source Deck Resources