The IAU invited us at Nature Astronomy to become a ‘media partner’, joining in their festivities by publishing a number of articles celebrating the huge progress in observing and understanding our Universe we have made over the past century. When the IAU began, optical astronomy was the only form known; now we are familiar with the Universe in every electromagnetic band, and we are making headway in understanding other cosmic messengers too. 

We decided to commission a series of News & Views articles looking back at significant papers over this centennial period, covering a wide variety of subjects from cosmology to planet Earth, observations and theory:

Jim Peebles wrote about Gamow (1948)’s idea of the hot Big Bang: https://www.nature.com/articles/s41550-019-0960-3

Emma Chapman wrote about Ewen & Purcell (1951), on the detection of the 21cm line of hydrogen: https://www.nature.com/articles/s41550-019-0752-9

Rachel Sommerville and Greg Bryan wrote on Davis et al. (1985), detailing cosmological simulations with cold dark matter: https://www.nature.com/articles/s41550-019-0939-0

E. Athanassoula and Albert Bosma wrote on Toomre & Toomre (1972, 1977) on galaxy interactions and mergers: https://www.nature.com/articles/s41550-019-0822-z

Pavel Kroupa and Tereza Jerabkova wrote on Salpeter (1955), discussing the stellar initial mass function: https://www.nature.com/articles/s41550-019-0793-0

Hans Olofsson wrote on Solomon et al. (1971), reporting the first detection of CO in a circumstellar envelope: https://www.nature.com/articles/s41550-019-0774-3

Nathalie Cabrol wrote about Sagan et al.’s 1993 paper on searching for life on Earth with the Galileo spacecraft: https://www.nature.com/articles/s41550-019-0839-3

In addition to this News & Views series, we also commissioned some longer articles on astronomical events during the past 100 years.

David Buckley wrote about the growth of astronomy in South Africa: https://www.nature.com/articles/s41550-019-0771-6

Stephen Pompea and Pedro Russo recounted Eddington’s eclipse journey to measure the deflection of light by the Sun: https://www.nature.com/articles/s41550-019-0893-x

And Luis Crispino and Santiago Paolantonio recounted the failed attempts that preceded Eddington’s success: https://www.nature.com/articles/s41550-019-0995-5

We also had a report from a ‘100 Hours of Astronomy’ event in Mexico from I. Villicaña-Pedraza et al.: https://www.nature.com/articles/s41550-019-0875-z

And our Editorial from a year ago was on the subject of the IAU’s 100^th anniversary: https://www.nature.com/articles/s41550-019-0708-0

For details of the other events and projects that went on to mark this occasion, please visit the IAU100 website: https://www.iau-100.org/

Banner image credit: IAU/Maique Madeira