The story of the discovery told by Philippe DUPOUY
Like most audiens (members of the mailing-list Aude) after the day's
work, consultation of the electronic mailbox
Aude server to read the latest astronomical news and there, message
from Alain Maury announcing the latest comet discovered by Jean Mueller
C/1997J1, without specifying celestial coordonates. As I did all the
asteroids audiens every fine-weather days for several weeks, I tell
myself that to change, I will make additions to positions on a comet
and bring my modest contribution.
I send a personal message to Alain, to obtain the ephemeris from 1997J1
which I received on the evening of May 7, 1997.
A reading of the declination, I "tick" a little. The camera "Hi-SIS22"
behind the LX200 allows me only 60 degrees (for stories of adapter
rings) and the sky is over not terrible, alternation of sunny and
cloudy. It is 9:30 p.m. local, the comet is almost at Meridian ... I
have to do an article for a future 'CCD et Télescope' .. .. an
electronic circuit to finish .... To Be or Not To Be ..?
I decided to observe, "tomorrow's Holiday," "I'll can sleep", "prose will wait".
Here we go in mechanics (another of my hobbies!), removing the
camera, replacing the ring too long (1O mm to win!). After fruitless
searches for replacement, I delete the adapter 42/75 to 42/100 and I
dare screw directly the 42/100 of the camera into the telescope's 42/75
. A portion of the net enough to maintain! 8.5mm won, whew! Delta
Raaaaahh! the two screws from the "homemade" shutter go beyond and the
brake lever alpha stumbles on camera's parallel plug.
Never mind, I Demount all, the hailstones rattling on the dome. After
removal and leveling of embarrassing bodies, re-assemblage, camera
finally passes into the fork. Delta orientation:
74° 30 while comet's delta on May 8 at 0h UT is 73°56.3.
The sky was
again clear; so I open the dome and I go fast in the air conditioned
room where I can do everything remotely over LAN (That's the object of
the CCD and Telescope article).
Timing clocks, focus, pointing, it is 11:28 p.m. UT when the 1 st image
from 1997J1 appears.
Quick glance at the screen at right which shows
the field of standard-POSS RealSky "pile-poil", let's go for 7
exposures of 30 s in binning 2x2.
Small-break snacks, storage, monitoring of clouds outside and on
another screen on the left Meteosat live.
0h 15 UT: recovery of a 2 nd round, the field is still there, but J1
moved down from the image, I recenter a bit and I see a 2nd spot a
little brighter at the bottom in border field ... Surely a small
galaxy. 7 exposures of 30s.
"It's still strange, this vague spot ... Almost the same place, RealSky
shows a small star, certainly a distant galaxy. I change the thresholds
of visualization, the star is punctual!
So .. it's not a galaxy, then a comet? Failover patch / windows and I
consult Megastar. Nothing. Well, we'll see if it moves on the 3 rd
1h 02 UT: 3rd series, like it has moved a few seconds, it's a
comet! "It must be known," "Megastar is the demo version, retrieved
from the web, I don't have all the comets", "plus the Palomar raking in
the corner "....
1h 19 UT: 4th series, 1997J1 which continues its fast race is almost as
close as the unknown. At this time, I tell myself it is great to have 2
comets in a field of CCD, the animation will be beautiful.
1h 49 UT: 5th round, they are still there both, 1997J1 begins to
recede. Immediately after, the clouds came, I took the opportunity to
make the "black", the flats will be made from pictures of the night.
It's from this moment that I've started to "gamberger". I didn't dare
to send immediatelly an email to B. Marsden.
Jean-Francois Lahitte will
treat the images in the afternoon, we will send all together, not to
seem ridiculous, you never know. "I didn't manage to go out of the
observatory, I moved on channel2 Meteosat, to see the cloud cover
elsewhere throughout Japan under the clouds, the U.S. too, except
California and Florida, Quebec was covered.
Would it a hope?
But hey, do not dream, now sleep, he began to emerge ...
15h local this May 8: back to the observatory, J-Fr Lahitte was
currently processing images of asteroids still in stock. After
treatment and reduction of cometary positions with QMIPS32 I was
I finally decide to send the mail to the IAU. It was 17:15.
I can not tell too torment
at that time. After that, the waiting for a response from Marsden,
finding phone numbers of members Aude for an observation at night.
Around 19:30 in the mail consultant, I received like everybody the
message "SUPER IMPORTANT" from Michel Meunier.
I called him (after
Minitel research) and gave him confirmation of our common observation.
Then we discovered the anxiety and it lasts. At nightfall, we could
remake the unknown, and Morata warned.
The first message from Marsden came on May 9 at 3:45, thanking us for our measures from the 8 and those we have just sent.
Following the episode is told by Alain Maury.
I want to thank with a warmth inversely proportional to the coldness of
the comet, Alain Maury who has delegated to me a discovery that could
have done himself, Christian Buil for his selflessness in sharing his
passion through the wonderful tools such as CCD cameras and processing
software that never ceases to evolve and Jean-François Lahitte that
help me effectively for treatment.
Lively first amateur CCD comet, and lively AUDE.