- Scientists from the University of Geneva announce that a previously-known Neptune-sized exoplanet, HAT-P-11b, has a slowly-escaping helium atmosphere.
- New research suggests Europa, a moon of Jupiter, may be covered in tall, jagged ice spikes, presenting a problem for any potential landing on its surface.
- JunoCam captures an image of Jupiter's "brown barge", a cyclone-like shape that has weather patterns in Jupiter's atmosphere.
- The European Southern Observatory's Very Large Telescope captures an image of PDS 70b, making it the first clear image of a planet forming from the disk of gas and debris surrounding its host star.
- Ten new moons are discovered around Jupiter, raising the count to 79 confirmed moons. One of these new moons, S-2016 J 2, nicknamed "Valetudo", is notable for orbiting backwards compared to the other moons in its vicinity, and may collide with one of them in the future.