The central region of globular cluster Messier 4

The globular cluster Messier 4 (M4 for short) is located about 6,000 light-years away. On the sky, it is seen in the southern constellation Scorpius, It is an ensemble of about 500,000 stars, held together by their mutual gravitational pull. There are about 150 such clusters in our Galaxy, and M4 is the one closest to us.

This colour picture has been obtained by combining three images taken through three different filters at the wavelengths of blue, green, and red light. They were obtained during the night of May 22, 1998. In this way, the stars are seen in their true colours, ranging from blue for very hot stars (about 10,000 degrees) to red for the cooler ones (about 4,000 degrees).

With an exposure time of only 2 minutes, the VLT has been able to detect in the blue light stars as faint as magnitude 24. This corresponds to 15 million times dimmer than the faintest stars visible to the naked eye. This was achieved even though the image has a fairly high background, being taken with the Moon above the horizon (3 days before New Moon, with 18% illumination). The large mirror surface of the VLT UT1 (53 m 2 ) and its ability to produce very sharp images (measured as 0.53 arcsec on these images), unequalled by any ground-based telescope, ensures that faint objects may be observed extremely efficiently, especially under the good conditions that prevailed during this observation.

Note that, because of the limitations in the printing process, these faint stars cannot easily be seen in this glossy reproduction.

Crédito:

ESO

Sobre a imagem

Id:eso9820c
Tipo:Observação
Data de divulgação:27 de Maio de 1998
Notícias relacionadas:eso9820
Tamanho:1384 x 1317 px

Sobre o objeto

Nome:Messier 4
Tipo:Milky Way : Star : Grouping : Cluster : Globular
Distância:5500 anos-luz
Constellation:Scorpius
Categoria:Star Clusters

Formatos de imagens

JPEG grande
299,8 KB

Papéis de parede

1024x768
167,0 KB
1280x1024
237,9 KB
1600x1200
312,0 KB
1920x1200
348,1 KB
2048x1536
447,7 KB

Coordenadas

Position (RA):16 23 34.45
Position (Dec):-26° 31' 25.90"
Field of view:1.56 x 1.48 arcminutes
Orientação:O norte está a 42.6° à direita da vertical

Cores e filtros

BandaTelescópio
Óptico
B
Very Large Telescope
Óptico
V
Very Large Telescope
Óptico
R
Very Large Telescope