ESA title
Centaurus A: Far-infrared and X-rays
Science & Exploration

The dark heart of a cosmic collision

04/04/2012 3138 views 3 likes
ESA / Science & Exploration / Space Science / Herschel

Two of ESA’s space observatories have combined to create a multi-wavelength view of violent events taking place within the giant galaxy of Centaurus A. The new observations strengthen the view that it may have been created by the cataclysmic collision of two older galaxies.

Centaurus A is the closest giant elliptical galaxy to Earth, at a distance of around 12 million light-years. It stands out for harbouring a massive black hole at its core and emitting intense blasts of radio waves.

Centaurus A: Visible light
Centaurus A: Visible light

While previous images taken in visible light have hinted at a complex inner structure in Centaurus A, combining the output of two of ESA’s observatories working at almost opposite ends of the electromagnetic spectrum reveals the unusual structure in much greater detail.

The galaxy was notably observed by Sir John Herschel in 1847 during his survey of the southern skies. Now, over 160 years later, the observatory bearing his family name has played a unique role in uncovering some of its secrets.

New images taken with the Herschel space observatory with unprecedented resolution at far-infrared wavelengths show that the giant black scar of obscuring dust crossing the centre of Centaurus A all but disappears.

The images show the flattened inner disc of a spiral galaxy the shape of which scientists believe is due to a collision with an elliptical galaxy during some distant, past epoch.

Centaurus A: Far-infrared
Centaurus A: Far-infrared

The Herschel data also uncover evidence for intense star birth towards the centre of the galaxy along with two jets emanating from the galaxy’s core – one of them 15 000 light-years long. Newly-discovered clouds co-aligned with the jets can also be seen in the far-infrared.

“The sensitivity of the Herschel observations enables us to see not only the glow from dust in and around the galaxy, but also emission from electrons in the jets spiralling in magnetic fields at velocities close to the speed of light,” explains Göran Pilbratt, Herschel Project Scientist.

Centaurus A: X-rays
Centaurus A: X-rays

ESA’s XMM-Newton X-ray observatory recorded the high-energy glow from one of the jets, extending over 12 000 light years away from the galaxy’s bright nucleus.

XMM-Newton’s X-ray view shows not only the way that the jet interacts with the surrounding interstellar matter, but also the galaxy’s intensely active nucleus, and its large gaseous halo.

“XMM-Newton is well suited to detecting extended weak X-ray emission, often allowing us to see halos around galaxies for the first time,” notes Norbert Schartel, XMM-Newton Project Scientist.

The jets seen by both satellites are evidence of the supermassive black hole – ten million times the mass of our Sun – at the centre of the galaxy.

Component images
Component images

This unique collaboration, alongside observations from the ground in visible light, has given us a new perspective on the drama in objects like Centaurus A, with a black hole, star birth, and the clashing of two distinct galaxies all rolled in to one.

Contact for further information

Related Links

Science & Exploration

XMM-Newton overview - OLD

01/01/1970 67833 views
Open item
Centaurus A: Far-infrared and X-rays
Science & Exploration

The dark heart of a cosmic collision

04/04/2012 3138 views 3 likes
Read
Stunning new Herschel and XMM-Newton image of the Eagle Nebula
Science & Exploration

A New View of an Icon

17/01/2012 14226 views 11 likes
Read
Andromeda: our nearest large galactic neighbour
Science & Exploration

Andromeda’s once and future stars

05/01/2011 10963 views 18 likes
Read
Giant star IRC+10216
Science & Exploration

Recipe for water: just add starlight

02/09/2010 2772 views 8 likes
Read
The Herschel and Planck AAAF Grand Prix 2010 award ceremony
Science & Exploration

Herschel and Planck win the French Grand Prix

10/06/2010 1720 views 2 likes
Read
NGC 1999: Truly a hole in space.
Science & Exploration

Herschel finds a hole in space

11/05/2010 10657 views 32 likes
Read
The white dwarf and its companion
Science & Exploration

XMM-Newton uncovers a celestial Rosetta stone

03/09/2009 3045 views 1 likes
Read
Artist's impression of galaxy and HLX-1 (blue star to the left)
Science & Exploration

XMM-Newton discovers a new class of black holes

01/07/2009 5955 views 22 likes
Read
Illustration of a magnetar
Science & Exploration

Giant eruption reveals 'dead' star

16/06/2009 3631 views 6 likes
Read
Messier 82
Science & Exploration

XMM-Newton exclusive photo: Messier 82

08/04/2009 3368 views 4 likes
Read
ISO: Infrared Space Observatory
Agency

Observations: Seeing in infrared wavelengths

6396 views 19 likes
Read
Cold comfort for newborn stars - ISO unmasks the icy veil around the Eagle's fiery heart
Science & Exploration

Why infrared astronomy is a hot topic

11/09/2003 10646 views 35 likes
Read
Location of Lagrangian point (L2)
Science & Exploration

L2, the second Lagrangian Point

196263 views 1504 likes
Read