Echelle spectrum of QSO HE2217-2818
This UVES echelle spectrum QSO HE2217-2818 (U-magnitude = 16.5) is recorded in different orders (the individual horizontal lines) and altogether covers the wavelength interval between 330 - 450 nm (from the bottom to the top). It illustrates the excellent capability of UVES to work in the UV-band on even faint targets. Simultaneously with this observation, UVES also recorded the adjacent spectral region 465 - 660 nm in its other channel. The broad Lyman-alpha emission from ionized hydrogen associated with the powerful energy source of the QSO is seen in the upper half of the spectrum at wavelength 413 nm. At shorter wavelengths, the dark regions in the spectrum are Lyman-alpha absorption lines from intervening, neutral hydrogen gas located along the line-of-sight at different redshifts (the so-called Lyman-alpha forest) in the redshift interval z = 1.7 - 2.4. Note that since this exposure was done with the nearly Full Moon above the horizon, an underlying, faint absorption-line spectrum of reflected sunlight is also visible.
Créditos:ESO
Sobre a imagem
Id: | eso9944d |
Tipo: | Simulação |
Data de divulgação: | 5 de Outubro de 1999 |
Notícias relacionadas: | eso9944 |
Tamanho: | 3000 x 2049 px |
Sobre o objeto
Nome: | QSO HE2217-2818, Spectrum |
Tipo: | Early Universe : Galaxy : Activity : AGN : Quasar |
Distância: | z=2.4 (desvio para o vermelho) |
Categoria: | Cosmology Quasars and Black Holes |
Formatos de imagens
Papéis de parede
Cores e filtros
Banda | Telescópio |
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Ultravioleta | Very Large Telescope UVES |