September 2026

1. 30 Wed
   Science begins for Smile

   The European-Chinese Smile mission was declared ready to start science on 23 September, following in-space commissioning after its 19 May launch and arrival in its science orbit on 20 June. Smile will study how Earth's magnetosphere responds to the solar wind.

2. 29 Tue
   Galaxies in a cosmic house of mirrors

   ESA and NASA/CSA released a James Webb Space Telescope Picture of the Month showing the galaxy cluster MACS J0454.1-0300, whose gravity lenses and magnifies galaxies from up to 800 million years after the Big Bang. The image shows hundreds of galaxies missing from the 2014 Hubble view, and some lensed knots are magnified more than 300 times.

3. 18 Fri
   A galaxy spinning out of sync

   A new Hubble image shows spiral galaxy NGC 4698, about 55 million light-years away in the Virgo Cluster, with a bulge extending perpendicular to its disc and central stars and gas rotating out of sync with it. Astronomers suspect an external gas inflow or a minor merger caused the misalignment.

4. 3 Thu
   BepiColombo's Mercury arrival begins - full replay

   ESA and JAXA's BepiColombo mission began its Mercury arrival sequence on 3 September 2026, when the Mercury Transfer Module separated from the stacked spacecraft after eight years of cruising through the inner Solar System. This replay covers the livestream from ESA's ESOC in Darmstadt, including the separation and the first spacecraft signal.

Headlines link to esa.int. Summaries are ours, 1–2 lines; read the full story at the source.