Exploration and discovery
25 nuove immagini dallo spazio per i 25 anni del telescopio Chandra

The Chandra Space Observatory team has released a series of stunning new images.

Twenty-five spectacular images to celebrate the 25th anniversary of the Chandra Space Telescope, which has been scanning the sky with X-rays since 23 July 1999.

Happy birthday, Chandra!

On 23 July 1999, one of the most powerful space observatories was launched on board the space shuttle Columbia: Chandra, the X-ray telescope for peering into the hot, energetic regions of the Universe. With Commander Eileen Marie Collins – the first female pilot and commander of an American space shuttle – at the helm, the astronauts aboard Columbia were able to place it in a highly elliptical orbit, almost a third of the way to the Moon.

Since its launch into space, Chandra has been NASA’s flagship mission for X-ray astronomy in its fleet of “Great Observatories.” Chandra discovers exotic new phenomena and examines old mysteries, looking at objects within our own Solar System out to nearly the edge of the observable Universe.

25 years of service

To mark the momentous occasion, the space agency shared 25 never-before-seen views taken by Chandra, named in honour of Nobel Prize-winning physicist Subrahmanyan Chandrasekhar. The images demonstrate the breadth of the telescope’s capabilities, highlighting the variety of objects studied and the importance of X-band observations. From the colossal majesty of a galaxy cluster to the radiant light of newborn stars, the new images celebrate the spectacular nature of Chandra’s vision.

By combining Chandra’s X-rays with those from other space observatories and ground-based telescopes, astronomers can tackle the biggest questions and unravel the mysteries of the cosmos.

“For a quarter century, Chandra has made discovery after amazing discovery,” said Andrew Schnell, NASA’s Chandra X-ray Observatory project manager at the Marshall Space Flight Center in Huntsville, Alabama.

The new set of images is a sample of almost 25,000 observations Chandra has taken during its long stay in space.

The pictures

This montage contains 25 new images with data from NASA’s Chandra X-ray Observatory that is being released to commemorate the telescope’s 25th anniversary in space:

A montage of 25 images taken by Chandra and released by NASA. © NASA/SAO/CXC
A montage of 25 images taken by Chandra and released by NASA. © NASA/SAO/CXC

There is a broad range of astronomical objects in this collection. The images are arranged in a grid, displayed as five images across in five separate rows. Starting from the upper left, and going across each row, the objects imaged are: Crab Nebula, Orion Nebula, The Eyes Galaxies, Cat’s Paw Nebula, Milky Way’s Galactic Center, M16, Bat Shadow, NGC 7469, Virgo Cluster, WR 124, G21.5-0.9, Centaurus A, Cassiopeia A, NGC 3532, NGC 6872, Hb 5, Abell 2125, NGC 3324, NGC 1365, MSH 15-52, Arp 220, Jupiter, NGC 1850, MACS J0035, SN 1987A.

Here is a closer look at some of them.

The Pavo

Perhaps the most significant image is of NGC 6872, a spiral galaxy in the constellation of Pavo (Peacock). It is a galaxy that has never been photographed before and is therefore special.

NGC 6872, a spiral galaxy located in the Pavo (Peacock) constellation. © NASA/CXC/SAO
NGC 6872, a spiral galaxy located in the Pavo (Peacock) constellation. © NASA/CXC/SAO

NGC 6872 spans across a whopping 522,000 light-years, making it more than five times the size of the Milky Way. In 2013, a fascinating fact about the galaxy was discovered by a set of astronomers from different countries. These scientists from the United States, Chile, and Brazil scoured through archival data from NASA’s Galaxy Evolution Explorer and found it to be the largest-known spiral galaxy. However, the NGC 262, a galaxy that measures 1.3 million light-years in diameter, later broke its record.

Cassiopeia A

At the center is one of Chandra’s most iconic targets, the supernova remnant Cassiopeia A (Cas A). This was one of the very first objects observed by Chandra after its launch in 1999, and astronomers have often returned to observe Cas A with Chandra since then.

Cassiopeia A © NASA/CXC/SAO
Cassiopeia A © NASA/CXC/SAO

The Pillars of Creation

Chandra also looks at what happens at the start of the stellar life cycle, providing information about some of the youngest and most massive stars. Images of these stellar nurseries in the “25 for 25” montage include the Orion Nebula, Cat’s Paw, M16 (a.k.a., the “Pillars of Creation”), the Bat Shadow and NGC 3324. A view of a more mature star cluster, NGC 3532, is also included.

X-ray data are particularly useful for studying objects like this because young stars are often copious producers of X-rays, allowing stars that are members of clusters to be picked out of a foreground or background of older objects.

The Pillars of Creation © NASA/CXO/SAO
The Pillars of Creation © NASA/CXO/SAO

The Crab Nebula

The unmatched sharpness of Chandra’s X-ray images are perfect for studying the hot debris and energetic particles remaining behind after supernova explosions. Other examples in this new collection include the Crab Nebula, G21.5-0.9, MSH 15-52, and SN 1987A.

The Crab Nebula © NASA/CXO/SAO
The Crab Nebula © NASA/CXO/SAO

A full list of the 25 images celebrating Chandra’s 25th, along with the data included and what the colors represent, is available at: Chandra X-Ray Observatory

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