Yes, Comet ISON (a.k.a. C/2012 S1) has died.
It probably existed 4.5 billion years as a conglomerate of dust
and frozen gases, spending most of its time in the Oort cloud,
between our solar system and nearby stars. A chance
gravitational jostling by another similar body must have altered
its velocity in a way that brought it into the inner solar
system, and amazingly close to the sun. That's where it became
"unglued" by the sublimation of ice to vapor and commenced a
dispersal of fragments and dust that spread apart, never to be
together again. Within a couple weeks it probably became so
faint that only a large telescope could detect any of it.
I
was hoping the Discovery Channel interviewer
would ask me "What do you think will be your
lasting impression about Comet ISON?" And I'd
answer "That many people hate hypocrisy and
hype, especially when their government does
it!" But the question never happened, because
the interview was canceled, presumably because
Comet ISON died and there wouldn't be a
spectacular view of it in the morning sky to
justify the TV Special.
So why would I have given the "hypocrisy and
hype" answer? Because that's what most of my
"thank you" e-mails
stated (I'm not
accusing NASA or STScI or
CIOC of hypocrisy or hype,
I'm just relaying reader
comments).
My web page has had 215,000 visits (14 million
hits). At first I was puzzled by the interest
level in my web site. I didn't understand why
people championed an amateur being the first
to "recover" Comet ISON after the June/July
solar conjunction. Was it because I showed
that it was fainter than NASA's CIOC had
expected? Instead of being called a "killjoy"
for re-branding the "Comet of the Century" to
ordinary comet status, people wrote with an
underlying message that "the government has
misled us again." Another theme was "How come
an amateur beat NASA in recovering the comet?"
And as you all know, every society seems to
have a minority of "weirdo's" who in this case
claimed that the government was keeping a
secret about the comet's malicious intent. (I
admit to laughing at the
person who lifted an image
from my web page and
declared that the jet
feature was in fact a UFO
flying in formation.) But
the common thread to many of the e-mails
urging me to continue my web page had to do
with a desire to have a place for news and
information that was unbiased and not hyped. Even
some scientist colleagues of
mine, from years ago,
expressed appreciation to me
for a place that was free of
hype and could be trusted.
On the one hand I was glad that people
recognized my reports as straight-forward and
un-hyped. "Calling it the way you see it"
isn't always the best policy when a person is
employed. But I'm retired, so it never entered
my mind to alter my unvarnished
interpretations. On the other hand, I was
disappointed that so many people distrusted
NASA. I really don't blame the Russian
astronomer who invented the term "Comet of the
Century," but I question the aggressive public
outreach by CIOC which seemed to legitimize
the spectacular spectacle conjectures, which
they should have known would be picked up and
exaggerated by the media. I've given
considerable thought to this, and I sent CIOC
an e-mail suggesting ways that NASA might
consider for improving a public relations
shortcoming that they may not recognize they
have (receipt of the e-mail has not yet been
acknowledged).
Let's change subjects, and get back to the
comet. Keep in mind that "I'm no comet
expert!" Until July, when a fellow astronomy
club member issued a challenge to be the first
in the club to image the comet, I didn't know
diddley about comets. From what I have read
Comet ISON was unique at the outset in two
respects: 1) it came from the Oort cloud, so
was a pristine sample of the original solar
system nebula out of which the Earth and all
other planets formed, and 2) it would be a sun
grazer, allowing a more detailed analysis of
the comet's chemical makeup.
The initial estimate for the comet's size,
made almost a year ago, was erroneously large,
and this fed speculation that it would become
naked eye visible, and possibly very bright. A
large comet nucleus, such as 3 km diameter,
would be more likely to survive a close
encounter with the sun, but Comet ISON was
more like 0.6 km in diameter (based on MRO
HiRISE albedo). Jakub Cerny (Czech Republic)
correctly recognized the situation before
perihelion, when he circulated an analysis
that relied upon the many brightenings and
fadings as evidence that the comet was small.
After each brightening there was too much
speculation that the comet might, after all,
put on a spectacular show for the general
public. It's natural for the media to
exaggerate such speculation. Joe Rao
(long-time comet aficionado, TV weather
forecaster) noted that those who knew the most
about comets were wisely refraining from
speculating about Comet ISON's future, which
reminds me of the cliche: "Those who know
don’t talk, and those who talk don’t
know." Whenever the comet did something
unpredicted, the talking experts would say
"Comets are like cats, they have tails and do
whatever they want," and the cautious
predictions kept on coming.
It is probably true that astronomers who
specialize in the study of comets will learn a
lot about comets, and maybe even the original
solar nebula, from the many observations of
Comet ISON. I doubt that lay people will ever
appreciate these insights. This raises the
perennial question of whether taxpayer money
is justified being spent on such things. The
question isn't going away because NASA and NSF
seem to be shifting their research focus to
comets, asteroids and exoplanets, and the U.S.
Congress will be asking for answers. I
personally think that exoplanet research can
be easily justified (for philosophical
reasons), and I think that the study of comets
and especially asteroids can be justified for
practical reasons - because comet and asteroid
debris hit Earth every day (meteors and
fireballs), and a "near Earth object" (NEO),
i.e., a tiny asteroid, could impact Earth with
little warning.
I hope Comet ISON will be remembered more for
what we learn from it during the next few
years (yes, that's how long it will take for
the science results to happen), and less for
it's disappointment in being a "no show" for
the general public. I will remember Comet ISON
for both of these aspects; but in addition I
will remember Comet ISON for the thousands of
loyal viewers who checked my web site for
updates 215,000 times.
May
whatever is left of Comet ISON "rest in peace," drifting
in space, forever.
Bruce L. Gary
Hereford, AZ; USA
Acrilic
painting of Comet ISON by Sue Lynn Smith
(Artist/Author/Activist, Florida), inspired by B. Gary
images of Nov 14, 2013.
More Comet ISON and other paintings on eBay (contact
available by request).
"The skylark, however high it flies,
however heavenly its song, has a mortal body from which
the song arises, and an earthly home to which it may and
must return." Erwin
Edman, The Contemporary and His Soul (1931).
Return to
Comet ISON
observations web page
WebMaster: B. Gary.
This site opened: December 13, 2013