# A Collection of Adonis Images

Volcanism of Io
Io has been monitored between 1997 and 2000. This movie shows Io with different central Meridian. Two bright hot spots are visible Loki and Pele. Such short time data are useful to determine the difference of volcanism for both hot spots and for estimating their center-to-limb variations. (see Marchis et al., JGR, in press, 2001)

Adonis performance with the Reticon WFS in K-band.

 Corrected image is at top, uncorrected at bottom. The image has not been deconvolved. Source is on axis, mV=6.6. Lookup table is power 1/4, to henance the visibility of faint structures. The faint"bumpy" structures at the edge of the PSF halo are 0.5% of the peak intensity.

 Mpeg Movie of 5 uncorrected and 15 corrected 5 sec K-band ex posures, same object/conditions as above. Click on the image to see it.

Observations of Titan
Titan's leading and trailing sides observed with
ADONIS/ESO in 1994 and 1995 respectively. The data show the bright
equatorial feature on the leading hemisphere (right) and structure
with brightness at high latitudes in the darker hemisphere (left).
From Combes et al. (1997).

 Titan's leading side taken with ADONIS in 1994 at 2 micron. During the  same year, the Hubble Space Telescope observed Titan near 1 micron at  the same longitude. The two images are compared here. The same  bright features are observed. The ADONIS data afford a contrast  of about 30%, 3 times higher than the HST. Two or three distinct  sub-units can be observed within the equatorial bright region. These  are compatible with the presence of some relief covered with fresh  ice. The surrounding dark areas are attributed to water ice and  tholin deposits (Coustenis et al. 1995).
References:
Combes M., et al., 1997, Icarus, 129, 482.
Coustenis, A., E. Lellouch, J-P Maillard and C.P. McKay 1995. Titan's surface: composition and variability from the near-infrared albedo". Icarus, 118, 87-104.

Observations of Io

Io's Leading and Trailing sides observed with COMIC camera in October 96.
The bright and famous hot spot called Loki is clearly visible on the sub-jovian hemisphere (left image). The anti-jovian one looks completely different with several fainter hot spots which form the so-called "ring of fire". Before Galileo observations, only a few hot spots have been detected by groundbased observations (Loki) or with during the Voyager flyby (86). The majority of the hot spots indicated here, have been observed by Galileo/NIMS in 1996 (Lopes-Gautier et al.  1997).
These images has been processed using the IDAC deconvolution method (J. Christou et al. 1998).

References:
Marchis, F., Prange,R., Christou, J.C., First images of Io by Adaptive Optics, Icarus, to be submitted, 1999
Lopez-Gautier et al., Geophysical Research Letters, vol 24, no. 20, p. 2439-2442, 1997.
J.C. Christou, F. Marchis, N. Ageorges, D. Bonaccini, F.J. Rigaut (ESO), Deconvolution of ADONIS adaptive optics images, Astronomical telescopes and instrumentation (SPIE conference) - Kona, Hawaii USA 20-28 March 1998

AG Carinae nebula observed with and without coronographic device

Click on the images for magnification.

AG carinae nebula was observed by D. Le Mignantand A. Chalabaev in March 99 using the SHARPII+ camera and the coronograph device (mask radius of 1.00'') in J band (left image). After sky subtraction, a reference star has been substracted to AGCar to get rid of  the wings of the PSF. The intensity betwen the faintest dust structures and the star maximum is of about 10^5 (total integration time of 800sec). The light reflected by the dust component around this star is clearly visible. Fine structures are revealed in the close environnement of AGCar down to 3arcsec from the star. These ring-like dusty structures are in agreement with HST/WPC2 observations (ApJ, 448, 788). Thanks to the high dynamical range achieved by making use of the coronograph, the dusty structures and the nebula appear with a higher intensity in our image.
As a comparison, we present a SHARPII+ mosaic image (on the right) in the SW part of the AGCarinae nebula without any coronograph device. The star was put outside of the camera field-of-view (integration time of 60sec).In that case, even if adaptive optic technics improves by a factor 5 the FWHM, the observations close to the star are limited by the blinding wings of the PSF. Note that we did not subtract for the PSF wings. Still, dusty structures appear in the circumstellar environment down to about 8arcsec.

Eta Carinae

Eta Carinae nebula started to expand and fom after the giant outbursts of the central star in 1841 and 1890. I observed this object in April 98 with ADONIS. This image is a "true color image", a composite image of 3 images taken at different velocity shift through the Helium 2.0581µm emission line. To detect the faintest features in the nebula, I made use of the ADONIS coronographic mount and a Fabry-Perot etalon (R=1000). The use of the latter allowed to get kinematic informations on the nebula. The former device permitts to get longer integration time, thus increasing the signal to noise ratio over the entire nebula. The size of the nebula is 12"x18". Note that they are wonderful images on the eta car nebula taken with HST on the STScI/NASA image server

Dark Speckles
 Fig 1. Long exposure on a binary star (HD 222493) and after subtraction by a closed reference star.  \Delta(m_k)=4, \rho=0.9'', 600 frames (60 ms/frame), filtre SK. Fig 2. Same cube of data but processed by an algorithme of Dark Speckles. The companion appears clearly on the subtracting image. Dark-speckle improve the detection of faint companion.  See Labeyrie 1995, A & A 298, 544  Boccaletti et al. 1998b A&A SS 133, 395; and his web pagefor more explanations on this method.

HD 100546 dust disk observed with SHARP II+ and coronagraph
(Pantin et al. 1999)

The HD 100546 pre-main-sequence star was observed from the 23-24th night of June 1999.
We used the adaptive optics system ADONIS combined with Sharp camera to detect the disk in K' band. The seeing had a value of 1.2" in average. The field of view is 9x9 arcsec. We used the reference stars HD 97218 and HD 101713 to remove the starlight contribution and reveal the disk. IRAS and ISO/SWS observations had shown that this star is surrounded by a relatively dense disk which is likely to be  a precusor to Beta Pic-like disks. The disk extends on a projected size of 3.2 arcsec (corresponding to 320 AU since HD 100546 is located at a distance of 100 pc from the earth) and is seen with a tilt angle around 45 degrees.

You are not convinced? Just have a look on these two images (on the left the disc after PSF subtraction, on the right a PSF subtracted to another one)

Before the ADONIS system, there was the COMEON+ system which has a gallery here.