In early February this year,
Rod Stubbings wrote to me to tell me he had discovered a new Z Cam star. Since
this was his independent discovery, he wanted to write a paper on it, and asked
if I would be a co-author, since I was, as he put it, the “Godfather of Z Cam
stars.”
He explained in an email that
he had selected this star, OQ Carinae, from a list of CVs whose optical
behavior was essentially unknown at the time. “I just noticed OQ Car in in one
of the CV catalogs when I was adding more dwarf novae to my observing list,”
Rod explained. “Being an under-studied dwarf nova is what interested me. I was
searching for every dwarf nova that was basically ignored and wanted to find
out how they behaved.”
No one else was paying
attention to what seemed to most a garden-variety dwarf nova. Nearly all the
data ever collected on this star were Rod’s visual observations. “My first
observation of OQ Car was on July 16, 2000, so it’s been almost 14 years.”
So, what motivates an
observer to keep observing a star that no one else thinks is interesting or
worthy of his or her time? “I like detecting outbursts and I soon realized that
OQ Car was very active, so it was always good for an outburst,” said Rod.
But in January OQ Car began
to behave differently. Rod was the only one watching. “I knew the star very
well and after a normal outburst around 14.2 it had its usual fade to around
14.6. I expected it to fade further the next night. It didn’t; it stayed at
14.7 for a few nights and I thought, ‘now this could be interesting.’ After a
week at the same brightness I knew it was in standstill. Two weeks later there
was no doubt.”
His patience and persistence
had paid off. By the time Rod contacted me OQ Car had been in standstill for 30
days. There wasn’t any doubt in my mind he had discovered a new Z Cam star
either.
Now Rod wanted to write his
first paper as a primary author. He explained the motivation, “I knew no one else
was observing OQ Car. Basically, 90% of the observations were mine over a
14-year study. I have always wanted to write a paper myself, so this was the
perfect opportunity to present what I had found.”
Rod learned it takes some
patience and persistence when it comes to getting a paper accepted by a
peer-reviewed journal too. “When the first remarks came back from the referee I
was a bit surprised,” said Rod. “It was so obvious to me it was a Z Cam, as I
had observed this star for over 14 years. What I learned is that you can have
all the observational data you think is necessary, but you still have to make
your case and prove it in the paper.”
After some minor revisions
were made and additional data were added, the paper was accepted to the JAAVSO
and the pre-print was published on arXiv March 4, 2014. OQ Carinae: A New Southern Z Cam Type Dwarf Nova, by Rod Stubbings
and Mike Simonsen, http://arxiv.org/abs/1403.0754
Rod's discovery story is a
testament to the value of patience, persistence and visual observations. He has
given his visual observing program purpose by learning about the potential
targets that are out there to observe, and what there is to learn from them.
Then by consistently, purposefully observing those objects year after year he
has contributed to science and made a discovery only he can claim. It doesn’t
matter that a CCD might have been more precise, or been able to measure OQ Car
at fainter magnitudes. You can’t go back and measure the outbursts, quiescences
and the one standstill in the history of this star with a CCD. It’s too late.
It’s a good thing Rod was observing with his eye at the eyepiece night after
night.
He has some advice for visual
observers who might be feeling overwhelmed by the digital detector revolution. “I
know we are in the era of so many robotic surveys covering the sky but there is
still plenty of work for visual observers. Instead of wondering what to do,
make up our own projects on variable stars. For example, ASAS3 has been around
for a long time and collected data on so many stars you might ask, why observe
them? I have been looking at the ASAS3 light curves and noticed a lot of stars
with incomplete light curves or in some cases no observations.”
I asked him recently what
other under-observed or under-appreciated stars he might be monitoring. He told
me, “I started to observe SY Vol in July 2000 (also 14 years ago) which has
never been monitored well. But so far it has shown typical dwarf nova behavior,
although not as active as OQ Car.”
“The Wolf Rayet star WR 53 is
a total mystery to me,” he added. “It's not listed in VSX because it is a
constant star as observed by ASAS and other CCD data, yet I see variations as
well as other visual observers. At one stage my observations were showing an RR
Lyrae star, but it's a Wolf Rayet star. Then I have a stage where it was
constant at 10.6 for months, and lately it’s started to vary again. I don't
understand this one, but I will keep watching.”
Who knows what other
interesting behavior visual observers might detect patiently and persistently
observing their objects of interest night after night, year after year. One
thing is certain. If you’re not looking, you won’t see it.
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