A new view of an icon
This new Herschel Space Observatory image of the iconic Eagle Nebula using PACS/SPIRE is a three colour composite with colours assigned as (blue=70um, green=160um, red=250um). The 70 um and 160 um data from PACS and the 250 um from SPIRE. The imaging area, which in the original data is around 95 arcminutes (cropped in the above image to 25 arminutes) on the sky contains areas of active star birth. Herschel’s far infrared instruments for the first time in this level of detail have been able to peer through the vast swathes of optically opaque material, showcasing the thermal emissions from the vast clouds and dust, which make up the nebula.
Each colour shows a different temperature of dust, from around 10 degrees above absolute zero (10K) for the red, up to around 40K for the blue. In the far infrared the nebula shows its intricate tendril nature, with vast cavities forming an almost “cave-like” surrounding to the famous “pillars” which take on an ethereal ghostly appearance.
The region is located 6500 light years away in the constellation of Serpens, the Serpent, one of the original 48 constellations defined by the 2nd century astronomer Ptolemy in the Almagest. Discovered first for the star cluster now known as NGC6611 which lies at its heart in the 18th century by Swiss astronomer Jean-Philippe Loys de Chéseaux. It was later re-discovered and the nebula catalogued as M16 by Charles Messier in his famous survey of the sky. The nebula which covers an area of approximately 70 light years x 55 light years is a diffuse emission HII region with very low density partially ionized gas and cold dust.
It is the delicate tendrils and filaments of these, which Herschel’s unprecedented detector sensitivity can image in such detail. In 1995 the NASA/ESA Hubble Space Telescope’s image of the Eagle Nebula quickly became one of the most iconic images of the 20th Century. That image, made up of 32 separate smaller images, showed the pillars, being gradually eaten away by ultraviolet light from nearby stars. The tips of the pillars were also found to contain star forming regions, which are known as EGGS (Evaporating Gaseous Globules), and new studies using observations including these from Herschel have extended our understanding of these star incubators.
Herschel’s image, produced from just over 3 hours of observing on 11-12 September 2010 shows the famous ‘Pillars of Creation’ just below the centre. It is at the tips of these several light year long pillars where astronomers are now seeing in a whole new manner, extensive star formation, with cold dust and gas undergoing gravitational collapse providing the raw materials for this activity
ESA/PACS& SPIRE Consortium, Tracey Hill, Frédérique Motte, Laboratoire AIM
Paris - Saclay, CEA/IRFU - CNRS/INSU - Uni. Paris Diderot, HOBYS Key Programme
- Observation object: M16 in the Eagle Nebula
- Type: Nebula
- Instrument: Photodetector Array Camera and Spectrometer (PACS) & Spectral and Photometric Imaging Receiver (SPIRE)
- Observation date: 2010/09/12
- Right ascension: 18h 18m 37s
- Declination: -13° 48′ 47″
- Wavelength: 70-250 µm
- Width: 4071 px
- Height: 4106 px
- Upload date: 2012/01/17 – 15:32