Press Releases 2007

ESO PR Photo 07a/07

Central Parts of Comet McNaught

[Preview - JPEG: 868 x 400 pix - 244k]
[Normal - JPEG: 1736 x 800 pix - 564k]
[Full Res - JPEG: 2393 x 1103 pix - 844k]
[Full Res - TIFF: 2393 x 1103 pix - 7.55M]

Imaging of the central coma of Comet McNaught. Left: a raw image taken through a filter centred on the emission by CN gas. Middle: the CN image processed using the Larson-Sekanina algorithm to reveal spiral jets of gas from the nucleus. Right: A similarly processed image of the dust in the inner coma, showing a sunward plume and the dust being swept back into the tail. The tail direction is roughly downwards in these images, which are orientated with North up and have a field of view of 2.4 arcmin on a side.

ESO PR Photo 07b/07

ESO's New Technology Telescope

[Preview - JPEG: 400 x 582 pix - 160k]
[Normal - JPEG: 800 x 1163 pix - 398k]
[Full Res - JPEG: 2771 x 4030 pix - 1.12M]
[Full Res - TIFF: 2771 x 4030 pix - 13.6M]

ESO's New Technology Telescope at La Silla is unique in that it can observe very low on the horizon. The telescope is not housed in a traditional dome with a slot in the roof to look at the sky, but in an innovative enclosure design with a sliding roof and wall that open up to leave a view of the sky which goes all the way to the ground. The whole building then rotates with the telescope to track objects on the sky. Inside the building the telescope can swing up or down, and was built to be able to swing down far further than normal telescopes: the NTT can point at objects only 10 degrees above the horizon.

ESO PR Photo 07c/07

Spectrum of Comet McNaught

[Preview - JPEG: 634 x 400 pix - 232k]
[Normal - JPEG: 1268 x 800 pix - 572k]
[Full Res - JPEG: 4947 x 3121 pix - 4.4M]
[Full Res - TIFF: 4947 x 3121 pix - 44.2M]

Long slit medium resolution spectrum taken on 3 February 2007 and covering the spectral range 450-650nm (the spectral direction is along the horizontal axis, blue side to the left and red to the right). The spatial direction is along the vertical axis and covers about 80,000 km on the sky. The nucleus has been centred in the 1" (800 km) slit, and is located at the position of the solar continuum in the spectrum. The Sun direction is up and the tail direction is toward the bottom of the image. The many emission lines from the gaseous coma are spatially extended by several thousands kilometres and grouped in so-called molecular bands. The sodium (NaI D) emission is visible as the sharp and very extended line. In fact the sodium doublet (NaI D1 and D2 lines) is just resolved. On 3 February the flux that this line had in the inner coma dropped by a factor of 10 in only a few days. For sake of clarity only some of the most conspicuous features are annotated.

ESO PR Photo 07d/07

The Comet and the Laser

[Preview - JPEG: 400 x 590 pix - 344k]
[Normal - JPEG: 800 x 1180 pix - 760k]
[Full Res - JPEG: 1150 x 1696 pix - 1.3M]
[Full Res - TIFF: 1150 x 1696 pix - 5.7M]

Photograph of the comet tail from Paranal, after the comet itself had set, with the laser guide star system above Yepun (Unit Telescope 4) in the foreground. The laser is used to produce a fake 'star' on the sky to allow the changing atmosphere to be corrected. It works by making sodium atoms high in the atmosphere glow - these atoms may have originally come from comets like McNaught. Photo by Emmanuel Jehin, ESO