A look back at coverage of ISON

I had to smile with the arrival of the January 2014 issues Astronomy and Sky & Telescope magazines earlier this month. The cover of the former heralded “Comet ISON’s Final Stab at Glory,” while the latter proclaimed “Comet ISON’s Final Act.” Richard Talcott’s article in Astronomy was subheaded “This cosmic visitor should remain a fine binocular object as it skims near the North Star during its retreat from the inner solar system.” Editor Robert Naeye’s piece in S&T proclaimed “Comet ISON might be putting on a gorgeous display as you read these words… or maybe not.”

Both magazines arrived in my mailbox about a week after ISON went “poof” after passing within 730,000 miles of the surface of the Sun on Thanksgiving Day.

The fact that both publications carried articles about something we already knew wasn’t going to happen by the time the issues arrived in our mailboxes serves to illustrate the challenge of monthly print magazines trying to cover breaking news. The approaches of the writers revealed a bit about the editorial bent of the magazines. I decided to take a look back at how they covered ISON over the past year.

Astronomy was the first of the first of the two
major magazines to write about ISON, and made the
comet its cover story in November 2013.

Even though ISON was discovered in late September of 2012, the first mention of it in print didn’t come until the December issue of Astronomy, in which senior editor Michael E. Bakich wrote, “About a year from now, Comet C/2012 S1 (ISON) may well become the brightest comet anyone alive has ever seen. Just how bright it will get is currently a subject of debate.”

S&T didn’t mention ISON until January 2013, when the cover proclaimed “The Comets are Coming,” and contributing editor John E. Bortle, who has been writing about comets for the magazine since 1967, wrote “whether [ISON] will become a great comet remains unclear,” and he chided the “Internet wags” (guys like me) for their poor understanding of typical comet behavior and wild speculation and hype about ISON’s potential. That same month in Astronomy Bakich again used the “anyone alive” line, and channeled Spiro Agnew and William Safire when he noted in his article that “The nattering nabobs of negativism already are downplaying expectations. I, for one, am not drinking from their half-empty glass.” One wonders if he got an advance peek at Bortle’s copy.

There wasn’t much written about ISON for the next few months, though comets LINEAR and PanSTARRS got some coverage during the late winter and early spring. S&T stepped in with a little downward adjustment of expectations in April. Naeye wrote that predictions of ISON’s spectacular potential were premature.

“With our decades of experience covering such matters, we know better at S&T.” The issue also included an article looking back at the much-hyped Comet Kohoutek, the mid-1970s “dud of the century.” After that S&T would not spill one drop of ink on ISON until August.

Astronomy was more active in its coverage. In June David J. Eicher wrote about comets in his “From the Editor” column, using the “anyone alive” line from Bakich but also stressing how unpredictable comets can be. Eicher write about ISON and other comets in his column in six of the next eight issues, breaking only to note the magazine’s 40th anniversary and its website re-design. His “Snapshot” column at the head of each issue’s news section was about comets in four of those eight months.

There wasn’t much else in either of the magazines for the rest of the summer. Astronomy ran a monthly note in the Comet Search section of its observing guide each month beginning in July, and S&T added ISON notes to its observing section starting in August.

Sky & Telescope put ISON on
 its cover in December 2013.

The pace picked up a bit in September. Bortle wrote in S&T that “Some have been billing ISON as ‘the comet of the century.’ Is there a chance this won’t be an embarrassment?” Richard Talcott’s article in Astronomy that month also used a question mark on “comet of the century,” though the subhead noted ISON was “still two months from glory.”

In October S&T was dead silent on ISON, while Astronomy kicked it into gear. Talcott wrote a four-page article about viewing ISON during its approach, and Joseph Marcus wrote six heavily illustrated pages about “What Makes a Great Comet?”

Sky & Telescope showed more enthusiasm in November. Naeye wrote about ISON but continued to warn “Anybody who tries to give you definitive brightness predictions months in advance is either playing the hype game or doesn’t understand the unpredictable nature of comets.” The magazine also ran an eight-page article about great comets, written by Joe Rao, and some detailed observing charts and instructions. Astronomy went all-in, with a November cover story—"Comet ISON Blazes Into Glory”—and other features on the science of comets, superstition about comets, the anatomy of a comet, and a history of bright comets.

December was the month in which having to write about the news before it happened really became a pinch. Talcott’s story in Astronomy carried the sub-head “After a harrowing pass by the Sun late last month, this cosmic interloper should remain a grand sight throughout these long December nights.” S&T made ISON its December cover story, with articles by Bortle, who kept with his story line about the unpredictability of the matter, and others writing about comet science, viewing guides, and tips for taking images of comets. Both magazines had photo contests up and going.

Finally, January and the let-down. We learned just after Thanksgiving that ISON had disintegrated while skimming the Sun, before our January magazines hit the mailbox the first week of December. The final act was over before the curtain even came up.

The different approaches the two publications took to their ISON coverage are interesting. In one sense Sky & Telescope was “right.” It warned from the start that comets are unpredictable and that we shouldn’t get our hopes up too much. Astronomy made that warning, too, though it generally took a more hopeful approach and devoted far more space to ISON than did S&T, using the opportunity to write more about comets in general.

By this time you may be asking how Seattle Astronomy covered ISON. The answer is that we didn’t, making just one mention in a post back in May about the possibility of using ISON as a way to get people interested in astronomy. We passed along breaking ISON news and speculation on Facebook and Twitter.

The saving grace for the monthly magazines is that they, too can use their websites and social media to cover breaking news that is impossible to catch in print versions that go to press more than a month ahead of their mail dates. They have to write something, but it’s a particular challenge to deal with such unpredictable critters as comets.

Some amateur observers got a peek at ISON, and scientists made many observations and learned a lot more about comets, so in that sense it wasn’t a “dud.” But unfortunately ISON didn’t come close to becoming the spectacle we’d hoped for when its sungrazing nature was first recognized more than a year ago. We’re still waiting for the comet of the century.

SohCahToa and finding the angle of the Sun in the sky

In Friday’s post about the approach of the solstice I cheated and just looked up the Sun’s noontime altitude using Starry Night software. But the math geek in me decided to try to dredge up my high school trigonometry nearly 40 years since studying it. I’m happy to say that I’ve still got it!

I think that the only reason I remember SohCahToa is that we had a bunch of weisenheimers in our trig class, myself included, and we came up with a report called “SohCahToa East of Java,” a joke that required that you know your geological history and late-1960s disaster movies. SohCahToh is the standard mnemonic for remembering which values to use to figure sine, cosine, and tangent.

In our problem, we’re trying to figure the angle A, that of the Sun up in the sky, given that it’s above and behind a six-foot fence casting a 14-foot shadow. Since we know the length of the opposite side, the fence, and of the adjacent side, the shadow, SohCahToa says we use tangent: Tangent=opposite/adjacent. The inverse tangent gives you the angle, in this case 23.2 degrees. (Did you know that your iPhone has a trig calculator? I didn’t until I accidentally turned mine to landscape orientation when I was calculating something much simpler a few months back. So now you can figure triangle angles and trig functions wherever you go.)

Starry Night gave the Sun’s actual altitude that day as about 19.6 degrees. The difference can be attributed to the fact that the fence is a touch shorter than six feet, and the deck is raised off the ground a few inches, making the “opposite” side even a bit shorter. Close enough, though; I was out there in my jammies with a tape-measure, and it was about 20 degrees, so I was only taking approximate measurements!

But there you go. I even showed my work. SohCahToa!

A sign the Solstice is nigh

Even casual sky watchers must be noticing that the Sun is staying low in the sky all day, and that it is rising and setting way in the south. I looked down this morning and spotted a sign that the Winter Solstice is approaching in just over two weeks.

A large area of my back yard gets no direct
light from the Sun because it is so low in the
sky as the Solstice approaches.

An area of permafrost has formed on my deck, leftover from Monday’s blizzard that dumped nearly 1/32″ of snow in Seattle. Most of the ice is gone, except for an area in the shadow of the fence, an area that isn’t getting any direct sunlight this time of year.

Here’s where your high school geometry comes into play. The south fence is about six feet tall, and yet the shadow it is casting stretches for about 14 feet to the edge of the unmelted, unevaporated ice. A few calculations reveal that the Sun is getting less than 20 degrees above our local horizon to cast a shadow that long.

OK, I admit I just looked that up in my planetarium software, but if I remembered all of those triangle formulae I could have figured it out! Suffice to say the Sun is low in the sky, and winter is upon us.

This is one of many reasons that tomato plants prefer summer to winter. The garden bed in which our tomatoes were planted this year lies entirely inside this shadow area and is getting no Sun at all. This being Seattle, it doesn’t get so much Sun in the summer, either, but that’s another story.

You can use your astronomical knowledge anywhere! What signs have you spotted that the solstice is approaching?

Scanning atmospheres for signs of extraterrestrial life

Giada Arney thinks that life likely exists somewhere besides Earth. Arney, a third-year Ph.D. student in astronomy and astrobiology at the University of Washington, gave a talk at November’s meeting of the Seattle Astronomical Society about the search for the origins of life in the universe.

“Some of us like me who are astrobiologists think it’s likely that life has arisen elsewhere in the cosmos and perhaps elsewhere in our own solar system,” Arney said. “But so far the only evidence we have for life that actually exists is on this singular planet.”

Ph.D. candidate Giada Arney is planetarium coordinator at
the University of Washington, and used the facility, refurbished
a couple of years ago, to illustrate her talk about astrobiology.
This shot of Earth was part of the talk. Photo: Greg Scheiderer.

It’s hard to extrapolate from a single data point, but Arney is on the case. The educated guess that there’s some form of life out there stems from the fact that the raw materials are all over the place. Asteroids, for example, are loaded with water and carbon molecules—and much more.

“We’ve looked at the composition of various types of very carbon-rich asteroids, and we’ve looked at the specific types of carbon molecules that exist in those asteroids,” Arney said. “We found sugars, we found amino acids—the building blocks of proteins in our cells. We found nucleic acids, the building blocks of our DNA.”

“What this suggests is that these building blocks of life are easy for nature to synthesize and they’re cosmically common,” she said.

On top of that, Arney said study of the interstellar medium reveals lots of sugars and alcohols. This had me thinking, “Well, what else do you need?!” Arney said that the significance of these is that they’re the building blocks for amino acids. Astrobiologists have yet to pinpoint amino acids in the interstellar medium—it’s exceedingly difficult to pick out their spectral fingerprints—but Arney bets they’re there.

“This suggests that this complex carbon chemistry, that at least life on Earth requires, is cosmically abundant,” she concluded.

Arney’s research bailiwick is planetary atmospheres, and that’s where astrobiologists are going to look for evidence of life on other planets. There are plenty of potential places to investigate. Arney said that around eight percent of low-mass stars have an Earth-size planet in their habitable zones. She said a recent analysis of Kepler data that put this figure at close to 20 percent came in too high because of what she feels is an overly generous definition of the zone. Even eight percent, though, gives scientists a lot of planets to explore. The ultimate test will involve direct imaging and spectroscopy of the exoplanets’ atmospheres, something we can’t really do yet.

“Once direct-imaging missions become possible, we’re going to look for gases like water vapor and oxygen in the atmospheres of exoplanets,” Arney said. “Maybe that will give us evidence for life on these planets.”

The effort will require use of another rare element: cash.

“It will be a very expensive mission because it’s going to require a very big telescope,” she said, bigger even than Hubble or Webb. “You need to collect a lot of photons in order to measure the spectra of an exoplanet to have a high enough signal-to-noise ratio to be able to confidently say, ‘Hey, there’s oxygen in this planet’s atmosphere.'”

Arney expects life is out there.

“Microbial life is probably common, but the general consensus in the astrobiology community is that complex life and certainly intelligent life is probably remarkably rare,” she concluded.

The search continues.