Astronomy

The first (spectacular) images from the Vera Rubin super telescope

The observatory is located in the north of Chile, on a mountain at the foot of the Andes, on the edge of the Atacama Desert. Costing 800 million dollars, it will require as much to operate for the next ten years. The high, over 2500 metres, and dry location offers clear skies for observing the cosmos

24 June 2025

5' min read

The long-awaited first images of the Universe taken by the new hyper-technological American telescope dedicated to Vera Rubin, the great astrophysicist who revolutionised, in the last quarter of the last century, our view of the matter we see, and also do not see, in the cosmos, have finally been unveiled in a worldwide conference.

La nebulosa del Trifido ripresa dall’Osservatorio Vera Rubin, sovrapponendo 678 immagini in modo da rivelare i dettagli più difficili da notare, come le nubi di gas da cui si formeranno altre stelle.

Images that astonished even the most experienced professionals, incredibly detailed and of enormous proportions, placed one after the other in a kind of cosmic film that had never been seen before, so much so that the President of the National Institute of Astrophysics, Roberto Ragazzoni, indulged in a remark that until recently could not even be imagined.

"The Vera C. Rubin will allow us to add depth and dynamism to our observation of the Universe. With this 8-metre-class telescope, capable of continuously mapping the sky of the Southern Hemisphere every three days, we will enter the era of 'astro-cinematography' and will also be able to explore a new dimension: that of time, with which we expect to study the ever-changing cosmos."

Fully justified, as the Vera Rubin Telescope is very fast in taking the sky in seconds and also in moving around, much faster than the large telescopes we have now, which are dedicated to observing very small areas of the sky with great precision.

L’Osservatorio Vera Rubin, situato sul Cerro Pachón, a 2682 metri nel nord del Cile

The observatory is located in the north of Chile, on a mountain at the foot of the Andes, on the edge of the Atacama Desert. Costing 800 million dollars, it will require as much to operate for the next ten years. The high, over 2,500 metres, and dry location offers clear skies for observing the cosmos.

The Vera Rubin is not the largest telescope in the world, but it is a technological marvel. The main structure of the telescope has a primary mirror 8.4 metres in diameter, which collects the light coming from celestial objects and sends it back to a secondary mirror 3.3 metres in diameter and eventually the light goes to the largest camera ever made.

Very unusual in its set-up, it is extremely bright and quick to acquire, with motors that spin the 300 tonne structure in seconds: at full speed, it could complete a full rotation, 360 degrees, in just over half a minute. All this allows the telescope to quickly pan across the sky, taking up to 1,000 images per night, a feature that allows one to speak of astro cinematography.

La prima immagine completa dell’ammasso della Vergine. Si vede una varietà incredibile di oggetti celesti dalle stelle brillanti alle galassie spirali in primo piano a quelle visibili come piccoli punti luminosi

Satisfaction was also felt in Italy, where Inaf held a press conference from the splendid Palazzo dei Normanni in Palermo, home of the astronomical observatory of the same name, with many of the many researchers who had been personally involved in defining the scientific aims, design and realisation of the Vera Rubin Observatory, with a contribution that the Americans themselves described as indispensable.

The industrial contribution is also important, which can be seen in the special dome enclosing the telescope, which was made by EIE of Venice-Mestre, a group that has always been involved in the construction of the most important optical and radio observatories. The dome has a bevelled polygonal shape, an average diameter of 29 metres at the base and is 38 metres from the ground. Made of steel, and aluminium, with insulation material, it weighs approximately 60,000 tonnes. The dome is also special, as it has to keep up with the movement of the telescope, and in fact has a higher rotation speed than any other large dome made to date.

The completely innovative optical design allows a very wide and very deep image at the same time, in the sense that it can detect very faint sources. By scanning the entire sky every three or four days for ten years, it will discover millions of supernovae, distant exploding stars, as well as nearby asteroids whizzing by and billions of distant galaxies.

La camera fotografica del telescopio prima di essere montata all’Osservatorio

The real heart of the new observatory, however, is the world's largest digital camera: 3.2 billion pixels created by 21 groups of nine sensors, each group containing 144 million pixels. If we want to make an almost sacrilegious comparison, think of it as equivalent to 67 IPhone 16 Pros, only here the sensors are vacuum-sealed and kept at -74 °C to avoid disturbance from the electronics.

Thanks to the special optical design of this gigantic and extremely fast wide-angle lens, in just 15 seconds an image the size of 40 times the diameter of the Moon can be taken - to put it another way, it would take 400 4K TV screens to show it all. In the ten years planned for the operation of the camera, the final tally will amount to around 60 million billion bytes of data, a '6' followed by 16 zeros: 60,000,000,000,000,000,000.

As soon as the image is acquired, within seconds, it is sent to SLAC, where the Linear Acceleration Centre is located, a national laboratory operating at Stanford University for the US Department of Energy. There, software developed compares each new image with previous ones of the same portion of the sky, revealing changes in brightness or position in the sky. It is thought that up to ten million variations will be revealed each night. At least 1 in 10 images will currently contain trails or glows from passing satellites, starting with the thousands of satellites in the Starlink constellation. The software developed, however, seems to be able to eliminate these disturbances, which during the press conference were likened 'simply to gnats on the windshield of a running car.

Vera C. Rubin nel 1965 al Lowell Observatory

Vera Rubin, to whom the observatory is dedicated, did not have an easy life at the beginning of her career, but she transformed modern physics and astronomy with her observations showing that galaxies must literally be immersed in large haloes of dark matter, which determines the anomalous behaviour we see. An outspoken and sharp person, she had a great love for the stars from a very young age, and through her personal experience she tried, without much fanfare, to support women in science.

His work helped usher in a change of historic significance in astrophysics, namely the realisation that what astronomers have always been able to see is probably only the visible tip of a gigantic iceberg of things we do not yet know.

On all this, which is a great American achievement in the first place, hangs incredibly the sword of the Trump administration's science cuts, which threaten to take away from the US a record that has made it truly great.