If I had to choose a single image of the sky, it would be Carina. On this page it is the nebula of the Academic category, and that is no accident: it is a place where stars are born.
What it is
The Carina Nebula (NGC 3372) is one of the largest and brightest star-forming regions in the Milky Way, about 8,500 light-years away, visible from the southern hemisphere in the constellation of the Keel. It is a gigantic cloud of hydrogen and dust that hosts some of the most massive stars known, among them Eta Carinae, a system so unstable that in the nineteenth century it briefly shone as the second-brightest star in the sky before fading again.
Young massive stars emit ultraviolet radiation so intense that it ionizes the surrounding gas and makes it glow; at the same time, their winds sculpt the dust into pillars, cavities and rims. A nebula like Carina is an ecosystem: the stars already born are deciding, with their radiation, where and when the next ones will form.
The Cosmic Cliffs
On 12 July 2022 the James Webb Space Telescope released its first scientific images, and one of them was what is now known as the Cosmic Cliffs: the edge of a gaseous cavity inside NGC 3324, on the outskirts of Carina. It looks like a mountain range at sunset, but each “mountain” is light-years tall and what lights it is radiation from young stars outside the frame, above it.
What matters is not the beauty but what is seen for the first time. Webb’s infrared camera pierces the dust that hides star formation from visible light and reveals newborn stars inside the pillars, jets of material ejected by protostars and bubbles of gas pushed by stellar winds. It is a photograph of a process that takes millions of years, taken at the instant the stars are being born.
The image this page uses is that one, in its official ESA/Webb release, with the full credit in the nebula’s panel.
Why it is the academic nebula
A school is a nursery: a place where something forms under pressure and radiation, and where what is already formed sculpts what comes next. The Cosmic Cliffs are the best metaphor I found for ITAM and for the Bátiz, and the reason Carina, not Orion, is the one I like most.
One fact for the next time you see it
Eta Carinae could explode as a supernova at any time in the next few thousand years. When it does, it will be visible in daylight from Earth. I hope I am not looking at my phone.