Nebulae and views from space

Photos taken by satellites, the space station, the Hubble and James Webb telescopes (a veritable time machine) and Euclid reveal to us all the beauty and the unimaginable vastness of the cosmos: colliding galaxies, exoplanets, nebulae, planets…

Gazing at the night sky on a clear night is always fascinating; unfortunately, light pollution is making this pleasure increasingly rare, unless one ventures away from the cities. Fortunately, photos taken from space can also captivate us. And space telescopes, which are becoming ever more powerful, bring us back a wealth of high-definition images.

It is important to note, however, that the colours in the nebula images published by NASA and the ESA are generally not ‘real’ in the sense that our eyes would perceive them. Most are composites that combine several images taken through specific filters and assign a visible colour to each. This convention allows us to visualise the chemical composition of nebulae and produces images that are both scientific and aesthetically pleasing.

Nebulae, which play a key role in the formation of stars, are celestial objects generally associated with stars. Historically, the term referred to any diffuse region visible in the sky. However, in modern astrophysics, it refers to a cloud composed of gas and dust. There are three main types: diffuse, dark and planetary nebulae. Studying them helps us to better understand the life cycles of stars.

Before the 20th century, astronomers referred to all celestial objects with a diffuse appearance seen through their telescopes as ‘nebulae’ — including what we now know to be distant galaxies. It was not until 1924, thanks to Edwin Hubble’s work on the ‘Andromeda Nebula’ (which he demonstrated was in fact a galaxy millions of light-years away), that the distinction became established. Today, the word ‘nebula’ is reserved for interstellar clouds located within galaxies.

The planets closest to us are also worthy of interest. For example, the colours of Jupiter, particularly those of its Great Red Spot, have inspired me.

Colours of inspiration

Untitled, 27 April 2019: the Moon and Earth seen from space.
Untitled, 11 November 2019: a nebula.
Untitled, 23 February 2020: Jupiter.
Untitled, 27 June 2020 : a nebula.
Untitled, 16 September 2020: a nebula.
Untitled, 19 November 2021: the southern Sahara seen from space.
Untitled, 10 August 2022: Jupiter and its Great Red Spot.