- The first interstellar asteroid, 1I/2017U1 `Oumuamua passed in front our telescopes: it is a weird, elongated reddish object. More at ESO, IfA, Gemini, CFHT, NASA, and our results are published in Nature. Karen Meech gave a TED Talk on our discovery, and I contributed an ESO Blog post.
We also studied its complex rotation. Finally, studying its motion, we noticed a weird deviation from its orbit: it is being pushed by something, most likely cometary activity. After all, `Oumuamua is a comet! More at ESO, NASA/HST, IfA, CFHT (with a cool animation), ESA. This new result was also published in Nature, and I give more behind-the-scene details in a Nature Blog post.
- Trying to save the planet... With Andy Williams, I explain how in this ESO Blog on threatening Near Earth Asteroids.
- Weird tail-less comets, the Manxes, are coming from the
Oort Cloud in the outer solar system. This project is lead by Karen
the observations were
done with Gemini. We observed one of these Manxes in more details, and it turned out it is a rocky remnant from the formation of the terrestrial planets - the result was published in Sci.Adv; more at ESO, IfA, and CFHT - a nice summary in Gizmodo thanks to Maddie Stone.
- Halley's Comet is still observed! in March 2003, at the distance of
Neptune. This was also the "Astronomy Picture of the Day" on Oct.3.
I had also observed that comet in 1994, as it
passed the halfway mark (January 1994): observation of the
faintest solar system object ever observed. [at that time]. In 1991, I
detected a majour outburst on the comet - which should have been quiet
at that time. This outburst created some waves in the public. For
instance, a lady contacted me to ensure me that this was a direct
cause (or was it a consequence?) of the Gulf war. Also, a journalist
concluded that the comet had completely exploded (which in turned
french in this example).
- Comet Hale-Bopp was still very active in 2001, esp. considering the
distance at which it was. We observed it at the 2.2m at ESO in
Mar.2001; here is a nice color
image (and is also available in
elsewhere...). It was also an
"Astronomy Picture of the Day".
- The object 2000 OF8 was discovered as an asteroid. We found out
that it is really a comet
The Trans-Neptunian Object 1996 TO66 has been extensively
observed; we obtained many interesting resulst on that object,
including its rotation period. This is described in
Press Release, and in more details in one of
- A strange supernova, sn 1998 bw, which seems to be related
to a Gamma Ray Burst (May
98). An ESO
Press Release has been published on that object. This object turned out to be the key that unlocked the mystery of GRBs
Io, using the UH adaptive optics instrument on the CFHT.
Observations of Comet Hale-Bopp.
Hale-Bopp page contains plenty of info and links about that comet;
for nice pictures, check out
and Spectra page.
Rapid Changes in the Inner Coma of
Comet Hyakutake (March 1996):
acrobatic observations of this nice comet with a great telescope and a
The discovery of a Transneptunian Object: 1994
TG2 (October 1994): one more TNO (only about 60 were known at that time), but I
discovered this one :-)
- High Resolution HST Images of Pluto
and Charon (May 1994): the first detailed, direct look at
Pluto and Charon's surface, long before New Horizons.
Past and On-going Projects
- With the launch of Starlink's satellites, astronomers across the world started to wonder if, in a few years, there would be more bright satellites in the sky than stars. I contribute to study and model the visibility and effect of these satellites. Preliminary results were published. See my
satellite page for a primer, simulations, plots... and for custom-plots of satellite impacts for your place.
- Trans-Neptunian Objects: The MBOSS color database, a compilation and
analysis of published MBOSS photometry
- 67P+Rosetta: ground-based observations of comet 67P/Churyumov-Gerasimenko during the Rosetta mission.
- Castalia: a space mission to Main-Belt Comet 133P/Elst-Pizarro.
- Recovery and follow-up of potentially threatening Near-Earth Asteroids
- ESO's Cosmic Gems is a neat project to make good-looking astronomical images.
Google Scholar -
ADS custom query.
Satellite constellation simulators: two webtool to evaluate the impact of satellite constellations (Starlink, OneWeb...) on astronomical observations.
Astrolabe Generator, a web-tool to
produce "astrolabes" for your site (updated version at eso.org - The
one at IfA is outdated - new version 2020!)
preview of the cardboard version is available for Paranal.
a web-tool to monitor the conditions at ESO/La Silla. It also exists for ESO/Garching, at
MeteoMonitor - Garching.
an ESO/MIDAS package for astrometric calibration of scientific image (plates
and CCD); it can get its GAIA standard stars automatically through the
an ESO/MIDAS package for photometric calibration of CCD images, with
quasi-automatic identification of Landolt's stars, and interactive
edition of bad points.
- All-sky camera: I was involved with getting an all-sky camera on La Silla - the original one is still up and running after ...almost 20yr? LASC was state of the art at that time... Then on Paranal, a custom-developed camera was installed: ApiCam-3. Here is a link to the archives - go to the ESO webcam page for real-time access (and kudos to Apical for their great hardware and service).