Astronomers using the NASA/ESA Hubble Space Telescope have observed a visible counterpart to gravitational waves for the first time: a kilonova from merging neutron stars.

The atmosphere of an exoplanet can reveal a wealth of information, such as the planet’s temperature, its air pressure, and whether it is suitable for life. However, studying exoplanet atmospheres is one of the most challenging tasks in modern astronomy — and a challenge for Hubble too. This new episode of the Hubblecast describes how exoplanet atmospheres are analysed and what makes it such a challenge.

Throughout its 27-year history, Hubble has seen enough of the Universe to fill 100 episodes of the Hubblecast — 10 hours worth! These episodes have captured the science, culture, trials, and successes of Hubble, ranging from its spectacular images to its cutting-edge discoveries to its impact on society.

To many, Hubble is best known for its stunning images of celestial objects, but among astronomers it is admired for the valuable data it delivers. Hubble has helped revolutionise astronomy, including shedding light on dark matter and dark energy, lifting the veil on black holes, and peering into the dusty regions around stars to image exoplanets. This new Hubblecast is the second part of an exploration of some of Hubble’s most important discoveries throughout its history.

Since its launch in 1990, Hubble has revolutionised our knowledge of astronomy. From imaging the most stunning phenomena in the cosmos, to the study of the invisible parts of the Universe, to observing the most distant objects ever seen. Hubble’s sharp eye has been at the forefront of astronomical exploration. This new Hubblecast is the first part of an exploration of some of Hubble’s most important discoveries in its almost 27-year history.

Since astronomers discovered that the stars in the sky are other suns, humanity has wondered if they are also orbited by planets and if those planets host alien life. Since the discovery of the first exoplanet only 25 years ago Hubble is among the many instruments trying to answer these questions. This new Hubblecast tells the story of what we know so far and what we can hope for in the future.

Since Edwin Hubble discovered that the Milky Way is not the only galaxy in the Universe astronomers try to find out how many of them are there. This new Hubblecast focusses on the question “How many galaxies are there?” including the new numbers achieved in 2016.