PubMed Central describes itself as “a free full-text archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health’s National Library of Medicine (NIH/NLM).” NASA have begun adding articles to the highly searchable/filterable database. So a simple search for something like ‘Mars’ will search NASA-contributed and other articles in the database, returning 156 results:
This in turn you could lead you to a brilliant read like The Astrobiology Primer v2.0 with no fewer than 52 co-editors, authors, and contributors, with everything from biospheres to nucleosynthesis discussed:
Over time, this matter (also referred to as baryonic matter) fell into existing cold matter clumps to form clouds mostly composed of neutral molecular hydrogen. As densities increased in regions within the cloud, gravitational collapse triggered cloud fragmentation. Further collapse of the clouds led to increasing pressures and temperatures at their cores. Eventually, temperatures and densities in these cores reached levels required for nuclear fusion. This is how the first stars were born, beginning the era of stellar nucleosynthesis of heavier elements (Brom, 2013). This era of element formation began about 100 million years after the Big Bang and continues to this day (Fig. 2).
Nevermind the 4+ million other articles in the database! Basically, another lifetime of a wealth of reading at your fingertips, available online here.