Starting:
1997
About 15
000 galaxy observations later
At last …
SN 2001el
My story on the visual discovery of SN 2001el
on the morning of 17 September 2001
LAG (Berto) Monard
It was
Sunday 16 September 2001. It had been raining two days before and the clouds
still struggled to dissolve despite a strong wind. It was a week now since my
last observations.
In the
evening, it finally started clearing again and I got in some observations of
cataclysmic variables (CVs) and galaxies from the Grus and neighbouring groups.
The sky, now thoroughly cleaned from haze was pitch dark with bright and
twinkling stars, a typical case of good transparency and bad seeing. Under such
conditions the Milky Way, with Sagittarius around zenith looks impressive from
my rural site, which I estimate a rating of about 3.3 on the Bortle scale.
DSO-ing with a fast 12.5" Newtonian is quite rewarding then, but that's
not what I was after….
The
observations didn't last long. Cloud fragments came over and I had to retire
for the night. Hopefully it would improve again later in the night and I
counted on my regular insomniatic wake-up around 2 am. Observations of the
Fornax and neighbouring galaxy clusters were due, specifically SN 2001du needed
to be checked up.
The time
came and I waked up around two o' clock local time, exactly midnight UT. It
would be cold outside and I actually didn't feel like going out, but then I
remembered to have never regretted observations before dawn and there was Bob’s
recently discovered SN 2001du. So
out I went. Only hooked-on observers do that...
My
observatory is about 80 m from the house. It is orientated straight East and
overlooks the valley to the North East. Our property lies on a ridge and it's
seldom that there is no breeze. But this time it was barely noticeable. The sky
was open and looked steady. This is what I was hoping for.
While
walking I reflected on bad things that had happened in the world. Would my
observations also reveal some unexpected violence? Now was the time of
anticipation, the excitement that keeps the VS observer and SN searcher going.
I did the
usual routine, rolled out my trusted 12.5”f/4.8 Dobsonian, loaded the turret
with the usual set of eyepieces
and got started on some variable stars in the Hydrus region.
It was now
half past two and time for the hunt.
The first
galaxy I visited was NGC 908, one of my favourites with promising SN producing
characteristics and a good comparison sequence thanks to A Henden. Next came
the galaxies in Eridanus and then more to the South, the Fornax cluster.
The
foremost spiral galaxy in Fornax is NGC 1365. It’s an early spiral (SBb) of
large size and about 45 degrees inclined. Recently they derived a distance of
about 17 Mpc (H=75) to it, somewhat indicative for the cluster as a whole. It’s
here that SN 2001du resided. Its
positive observation and estimate of 15.1V could have possibly be the highlight
of my observing session.
After this
I did some more galaxies in Fornax and Eridanus.
The next
galaxy group that would follow in logical order, is in Horologium. But I have
the habit of keeping it over for later. It concerns the group with ao the
nearly face-on NGC 1433 and an edge-on spiral galaxy of no particular interest,
NGC 1448. Actually it is not that bad a group, but somehow it was not amongst
my favourite areas…
So up to
the South, to NGC 1559, a somewhat isolated late spiral (Scd) which had been
productive in the past. I have often wondered if that 13th magnitude
foreground star had anything to do with that.
The next
group I find quite interesting. It starts off the bright star alfa Dor.
NGC 1566
must be one of the better SN producing candidates, a pleasing face-on middle
type (Sbc) spiral galaxy with rich spiral arms. Surprisingly it has a clean
record.
Other
galaxies in Dorado are the nearby pair of NGC1549 and NGC 1553, and the edge-on
NGC 1515. Because of the pristine
conditions I also did the extra bit, NGC 1533 etc..
Then back
to Horologium. Starting from alfa and delta Hor, one gets to NGC 1512, which
has some convenient faint neighbouring stars, a clear view of them reassuring
good observing conditions. But
again there was no SN. Then a side trip to the warped NGC 1487. Next target,
NGC 1448…
Like NGC
134 it has nearby stars on both sides of its nucleus: in its case there is one
quite bright, but the other only clearly visible under good conditions. Those
conditions and both stars were present, so was a third star in between them….
Since my
move to my new site I have often had the need to consult the images, especially
under good observing conditions. Stars that were completely out of reach from
my previous suburban location, suddenly popped up. Galaxy neighbourhoods had to
be re-studied.
However
this new star very close to the nucleus, I should have picked up on previous
occasions. I was about to doubt my memory, but a look at the DSS image didn’t
show anything there. On later inspection there was a slight condensation,
probably a star forming region. It would make sense that SNe type II would
occur there.
I didn’t
need much time to realize what I was seeing. I was excited, possibly not more
than on previous occasions, when foreground stars imposted as supernovae or
planetoids as novae. NGC 1448 is far away for the MW and the ecliptic, so the
new star was unlikely to be a planetoid or nova. I would check this up anyway,
next morning.
But deep
inside I knew this one was real. I made an estimate of magnitude 14.6V for the
brightness using a preliminary sequence. An improved sequence would change that
later to 14.5V.
It would be
quite sometime before I would notify, so I carried on observing the remaining
parts of the program, including some more CVs that rose in the East.
I made
another observation of NGC 1448 and closed up just before dawn. It had been a
good observing session.
Soon I
would go to work. That’s where the e-mail would be sent from. I knew I had seen
and discovered a new supernova.
But was I the first to have seen it? ‘Probably not’ was my conclusion after
hours of considerations. I hadn’t seen e-mails since Friday. A lot could have
happened since. Probably there were e-mails waiting in my e-box, requesting
confirmation or follow up of a new supernova or a suspect in NGC 1448. Nobody
would believe my independent discovery. And I had decided in that case not to
forward any claims or chase any endorsement, but to hope for better luck next
time.
That were
my thoughts when I entered my office. I was prepared for the eventuality.
Still, I gave myself some chance for glory, but less than 50%.
In the mean
time Murphy had done his round in our workplace. The e-mail and internet
systems were not accessible. After several hours, my (hyper)tension was
growing, when there was some response when trying to log in. The posting list
flashed on the screen for a few seconds, then it all looped up again. It took
another hour before there was a steady and useable display of the messages, and
there were quite a number of them. I started reading titles….After about 400 of
them it was clear, nothing about NGC 1448. I couldn’t believe it. But then I
also noticed the lack of postings from the Australian region. That’s where I
would expect a notification from.
To make the
story short, the internet access locked up again. Sometime later it was working
again but nothing from Australia. I wrote an observation notification, and sent
it to SN observers for confirmation. After a few minutes, the connection packed up again and it was obvious that
my postings hadn’t gone through. I was in distress, as one ought to be. Later
on in the afternoon, the connection was somewhat re-established, but no reply
came back that day…
The clear
weather had gone but I was determined to make a follow up observation the next
night. Around local midnight I started to patiently observe weather proceedings
with the telescope in readiness. There were some openings in the clouds but the
air was heavy and moist. It took the best of an hour before I could catch
glimpses of my SN suspect, right at the observing limit. Some more time at the
telescope finally revealed some clearer appearances and I was able to estimate
it at 14.3V, 0.2 magnitude brighter than the discovery magnitude 22 hours ago.
The SN, if it were one, had brightened. It was important that the others would
know it as well. What if the clouds had persisted and my patience had been
less?
Now I was
very anxious to get at work and read the e-mails.
In the mean
time the internet technicians had sorted out most of the problems but the
internet access was slow. They also mentioned a virus.
However, I
got to read the e-mails. And there were replies from Australian SN searchers.
Nobody had seen anything yet, the weather had been bad but they would like to
confirm. I started rating my chances to over 80%… The next day would eventually
bring more certainty.
In one of
the e-mails from Japan Dr H Yamaoka urged me to send a notification with my
observing and observation particulars to CBAT, based on my own confirmation of
the SN suspect. A bit hesitantly I did so and made also reference to
confirmation reports to come. That e-mail contained the most important
information of the find, including all observations up to then. It was a
blessing that I did send it, as confirmation reports arrived during the night,
some requesting to send additional info to CBAT.
The
discovery had been confirmed by Greg Bock and A Wassilieff despite the terrible
weather conditions they had had during the early part of the night. Their
observations also showed a further brightening of the SN suspect. Possibly
there were more confirmation reports as I got e-mails from Chili and other
places. Those messages however were empty, a consequence of the state of our
network. But I was very pleased with the confirmations that had come through.
But then I
was also very distressed because of what had happened on our plot during the
previous day. Our house was broken into and plundered. There was a lot missing
and not much we could do about it than to phone the police and go through their
usual procedures. The insurance Co
had refused at the time to give cover unless certain (extreme) conditions and
precautions were met. I didn’t think there would be any need for insurance if
those conditions were fulfilled. We knew we were taking a risk, not a wise
decision as it turned out.
Fortunately,
all observing equipment in the observatory was still there and intact. Possibly
my dogs had kept them from moving to that part of the property.
Clouds
intensified that day and no observation would be possible for the next nights.
Thursday morning, I finally received news of the IAUC announcement of my
supernova, SN 2001el.
Well done,
Berto, I told myself, and so did many others. It had been a long wait.
I am very
thankful to those observers and sympathisers that went out of their way to help
confirming this nearby SN for which at this stage (22/09/2001) no type had been
communicated yet.
My
observation of this morning showed a further brightening of SN 2001el: 13.3V.
Possibly it is a type Ia.
Special
thanks to Alex, Brian, Bob, Greg, Hitoshi, Nick, Peter, Robin, and Taichi.
My
discovery of SN 2001el in NGC 1448 (Bob Evans found there SN 1983S) is now the
second one from South African soil! The first one was discovered by Jack
Bennett. It was SN 1968L in M83. He did so not so far from here, in a Pretoria
suburb under skies that were still dark then. He used a 5” elbow refractor,
exactly the same as my trusted apogee 20x120…
I intend to
find some more SNe in the near future.
Berto
Monard / 22 September 2001 /
Plot 39 /
Bronberg Observatory / South Africa &n!
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