A group of objects at redshift 3.04

This is a "true-colour" image of part of the sky field near the quasar Q 1205-30. Red, blue and yellow objects are displayed with their true colours, while objects at a redshift of about 3 and with strong Lyman-alpha emission lines have a bright green colour (see the text). Six Lyman-alpha Emitting Galaxy-building Objects (LEGOs for short) are marked by hexagons. The quasar (at the lower left) is marked by a larger hexagon and is seen to have an extended Lyman-alpha cloud in front of it, here visible as extended green light.

Technical information: this image is a colour composite, based on three images. The green channel is based on images with a total exposure time of 17.8 hours, obtained through a 2 nm wide, optical filter, centred at wavelength 490.6 nm and obtained in 1998 with the SuSI2 instrument at the ESO 3.58-m New Technology Telescope (NTT) on La Silla. The blue and red channels are based on 13 400-sec exposures in a B-filter and 15 250-sec exposures in an I-filter, respectively, both obtained with 8.2-m VLT ANTU telescope and the multi-mode FORS1 instrument. The field measures 3.0 x 1.8 arcmin 2. North is up and East is left. 

Credit:

ESO

About the Image

Id:eso0120b
Type:Observation
Release date:18 May 2001
Related releases:eso0120
Size:2940 x 1695 px

About the Object

Name:Q1205-30
Type:Early Universe : Galaxy : Activity : AGN : Quasar
Distance:z=3.04 (redshift)
Category:Cosmology
Quasars and Black Holes

Image Formats

Large JPEG
521.5 KB
Screensize JPEG
110.4 KB

Wallpapers

1024x768
133.2 KB
1280x1024
181.0 KB
1600x1200
239.6 KB
1920x1200
301.8 KB
2048x1536
338.1 KB

Colours & filters

BandTelescope
Optical
B
Very Large Telescope
FORS1
Infrared
I
Very Large Telescope
FORS1