VLT map of gas within NGC 7252’s minispiral

Eso_potw1806b_1024

eso_potw1806b February 5th, 2018

Credit: ESO/ESA/Hubble & NASA/J. Weaver et al.

This unusual image reveals the aftermath of a catastrophic collision between two galaxies, which happened about one billion years ago. The result? A single, very oddly shaped galaxy named NGC 7252, and curiously nicknamed the Atoms for Peace galaxy. At the heart of this merger remnant lies a fascinating “minispiral” — a rotating disc of glowing gas, bursting with star formation. Using the VIsible Multi-Object Spectrograph (VIMOS) instrument on ESO’s Very Large Telescope, astronomers were able to measure the movement of the gas within this disc, allowing them to map its rotation. Red regions indicate gas moving away from us, and blue regions towards us. Together, these colours reveal the galaxy's steadily rotating centre, as well as highlighting two flowing streams of hot gas north-west and south-east of the central region. Past studies suggested that the central spiral was rotating counter to the rest of the galaxy, but by comparing the movement of stars around the galaxy with the gas ionised by newly formed stars in the minispiral, we now know that they are in fact rotating in the same direction. Such a detailed map is possible due to the Integral Field Unit (IFU) on VIMOS, allowing astronomers to study the gas in NGC 7252 with a comprehensive "mosaic" view. Much like the way a fly observes the world, an IFU divides its subject into many cells, or pixels, generating a spectrum for every single one. The resulting information is arranged into a 3D data cube, which is particularly useful in studying extended objects in just one shot.

Provider: European Southern Observatory

Image Source: https://www.eso.org/public/images/potw1806b/

Curator: European Southern Observatory, Garching bei München, Germany

Image Use Policy: Creative Commons Attribution 4.0 International License

Image Details

Image Type
Observation
Object Name
NGC 7252
Subject - Local Universe
Galaxy > Type > Interacting
Eso_potw1806b_128
 

Position Details

Position (ICRS)
RA = 22h 20m 44.7s
DEC = -24° 40’ 42.3”
Orientation
North is 0.1° CCW
Field of View
1.6 x 1.1 arcminutes
Constellation
Aquarius

Color Mapping

  Telescope Spectral Band Wavelength
Red VLT (VIMOS) Optical 336.0 nm
Blue VLT (VIMOS) Optical 475.0 nm
Red Hubble (WFC3) Infrared (J) 1.1 µm
Green Hubble (WFC3) Optical (g) -
Blue Hubble (WFC3) Optical (u) -
Spectrum_base
Red
Blue
Red
Eso_potw1806b_1280
×
ID
potw1806b
Subject Category
C.5.1.7  
Subject Name
NGC 7252
Credits
ESO/ESA/Hubble & NASA/J. Weaver et al.
Release Date
2018-02-05T06:00:00
Lightyears
Redshift
Reference Url
https://www.eso.org/public/images/potw1806b/
Type
Observation
Image Quality
Distance Notes
Facility
Very Large Telescope, Very Large Telescope, Hubble Space Telescope, Hubble Space Telescope, Hubble Space Telescope
Instrument
VIMOS, VIMOS, WFC3, WFC3, WFC3
Color Assignment
Red, Blue, Red, Green, Blue
Band
Optical, Optical, Infrared, Optical, Optical
Bandpass
-, -, J, g, u
Central Wavelength
336, 475, 1100
Start Time
Integration Time
Dataset ID
Notes
Coordinate Frame
ICRS
Equinox
J2000
Reference Value
335.186207073, -24.6784261606
Reference Dimension
2461.0, 1614.0
Reference Pixel
1230.5, 807.0
Scale
-1.10126810617e-05, 1.10126810617e-05
Rotation
0.11999999999999911
Coordinate System Projection:
TAN
Quality
Full
FITS Header
Notes
Creator (Curator)
European Southern Observatory
URL
http://www.eso.org
Name
Email
Telephone
Address
Karl-Schwarzschild-Strasse 2
City
Garching bei München
State/Province
Postal Code
D-85748
Country
Germany
Rights
Creative Commons Attribution 4.0 International License
Publisher
European Southern Observatory
Publisher ID
eso
Resource ID
potw1806b
Metadata Date
2023-10-11T09:19:59.199978
Metadata Version
1.1
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Detailed color mapping information coming soon...

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There is no distance meta data in this image.

 

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