Misinformation Age : Northern Lights Edition

Aurora November 7, 2004

   This past week the Sun unleashed an X-1 class flare(X is the strongest class, X-1 is the weakest of X-class flares) in the general direction of Earth.  NOAA's space weather forecast center put the odds of an auroral display for the mid-latitudes (which includes all of Michigan) at 50% for the 24-hr forecast period.  The Detroit Free Press posted an article on their website that included  phrases like "could be visible", "might get a treat", "there is a possibility" all reflecting the uncertain nature of how particles cast off by the Sun will react with the Earth's magnetic field.   So why did the headline writers attach the headline "Solar Flare to bring Northern Lights over southeast Michigan tonight"  that made it sound like a sure thing?  Here is a link to the article.  http://www.freep.com/article/20140108/NEWS06/301080120/Michigan-northern-lights

  WDIV channel 4's website had an article that included the appropriate 'coulds','mays' and 'mights'.  Then they included a follow-up article that included a (cellphone?)photo that appears to show Light Pillars (vertical columns of light which are caused by ground lighting being reflected by horizontally faced ice crystals suspended in sub-zero air) and declared "We did get some Northern Lights".  http://www.clickondetroit.com/weather/we-did-get-some-northern-lights/-/1719236/23855032/-/gahm35z/-/index.html
  
  If the photo accompanying the article is an auroral display they scooped the whole skywatching community because no one else in the lower 48 states reported or submitted photos of the northern lights to spaceweather.com 
   If there had been a display visible from southeast Michigan the aurora gallery of spaceweather(dot)com would have been flooded with photos from the northern tier of states.

  Nearly everyone says they want to see the Northern Lights,  but how badly do you want to see them?  You can't rely on news outlets.   You don't get birding tips from them so don't get your astronomy tips from them either. You have to research it yourself and a good place to start is the aforementioned  spaceweather.com 
  Once you figure out their forecasts, it only takes seconds to assess the probability of an auroral display.  Then when there is a 50% chance of a display in the next 24 hours you have to consider that at least half of those hours are either bright twilight or daylight, so your chances are now down to lower than 25%.  And if you're only going to check the sky in the evening (between 7 PM and midnight) your chances are down to 5/24 x 50%, or about 10%.  That 10% chance assumes you live away from a major metropolitan area where stray light washes away the contrast needed to make the aurora visible.  Contrast in  night sky can also be faded by bright moonlight.  So if most or all of the above apply the original 50% forecast is down to about 1%.

  This isn't rocket surgery, but it does take some effort.

Oops: Comet ISON not dead anymore. 11/29/13

Image from NASA's SOHO satellite

  Yesterday I posted about the death of Comet ISON..... disregard the obituary because it appears to have been resurrected like a giant trick birthday candle blown out by the solar wind.   Although the comet is not dead, it lost some mass and may have fragmented.  It will not be the 'Comet of the Century',  because that would have happened yesterday at the time that its demise appeared to take place. 

  For a more informed explanation here is a cut and paste from today's :spaceweather.com front page

   COMET ISON LIVES (UPDATED): Cancel the funeral. Comet ISON is back from the dead. Yesterday, Nov. 28th, Comet ISON flew through the sun's atmosphere and appeared to disintegrate before the cameras of several NASA and ESA spacecraft. This prompted reports of the comet's demise. Today, the comet has revived and is rapidly brightening. Click to view a SOHO coronagraph movie of the solar flyby (updated Nov. 29 @ 1800 UT):

Before the flyby, experts had made many predictions about what might happen to the comet, ranging from utter disintegration to glorious survival. No one predicted both.

Karl Battams of NASA's Comet ISON Observing Campaign says, "[colleague] Matthew Knight and I are ripping our hair out right now as we know that so many people in the public, the media and in science teams want to know what's happened. We'd love to know that too! Right now, here's our working hypothesis:

"As comet ISON plunged towards to the Sun, it began to fall apart, losing not giant fragments but at least a lot of reasonably sized chunks. There's evidence of very large dust in the long thin tail we saw in the [SOHO coronagraph] images. Then, as ISON plunged through the corona, it continued to fall apart and vaporize, losing its coma and tail completely just like sungrazing Comet Lovejoy did in 2011. What emerged from the Sun was a small but perhaps somewhat coherent nucleus that has resumed emitting dust and gas for at least the time being."
Battams emphasizes that it is too soon to tell how big the remnant nucleus is or how bright the resurgent comet will ultimately become. "We have a whole new set of unknowns, and this ridiculous, crazy, dynamic and unpredictable object continues to amaze, astound and confuse us to no end. We ask that you please be patient with us for a couple of days as we analyze the data and try to work out what is happening."

RIP Comet ISON

   The comet persistantly billed as the "Comet of the Century" by the astronomically challenged, did not survive the harsh environment of the Sun.  It vaporized in the hours preceding its closest approach.


One of the last images before disintegration at 12:12 EST

Here is a link to a video showing the demise of the comet.

http://www.spaceweather.com/images2013/28nov13/rip_anim2.gif?PHPSESSID=7tlsiusd9oqpeir5n1492n1tg0

  There is still a chance that the remnants may be visible from a dark sky as a headless ghost comet, with its tail extending up from the eastern horizon before sunrise in the next couple of weeks.



Misinformation Age : Comet ISON edition

    A little knowledge goes a long way toward muddying the facts.  In September 2012 the International Scientific Optical Network (ISON), an astronomical research group discovered a comet that is destined for a close encounter with the Sun next week.  The intense heating of the icy visitor during perihelion (closest point in its orbit to the Sun) had the potential to create an historic apparition that would dazzle even the casual observer.  Responsible astronomers questioned at the time of the comet's discovery explained that comets are notoriously unpredictable and that many previously anointed  'Comets of the Century'  failed to live up to expectations.  It was also stated that a clearer picture of this comet's fate couldn't be determined until August of this year at the earliest.

  Now that August has come and gone,  it's apparent that the 'Comet of the Century' train has left the station but that hasn't stopped the media outlets from using that term to describe this comet.  In the past few days the comet has undergone significant brightening but not enough to overcome the dismal stagnation that it went through since late summer.   Here are a couple of headlines that appeared this week..... 'Comet Of The Century' Is Coming, And Here's Where You Can See It'  (Huffington Post).............."Looking for the 'comet of the century'? Watch ISON online"  (NBC News)........."Interactive ‘Comet of the Century’ Tracker: Where’s ISON Now?" (TIME Magazine).  

  Anyway,  with a little effort this morning I was able to get a lousy photograph of the smudge of ice that Comet ISON currently is.

Don't see it, do you?

Here is a screengrab from astronomy program Starry Night that provides clues.

Comet of the Misinformation Age

Prepare to be disappointed (or amazed)

   A word of caution - comets are notoriously fickle, spectacular predictions based on early observations often lead to big letdowns.

      On November 28, 2013, Thanksgiving Day in the U.S., the midday Sun may have a companion as it travels across the sky.  Comet ISON (  C/2012 S1) will execute a hairpin turn as it passes 1.8 million km above the Sun's surface.  Considering the diameter of the Sun is 1.3 million km this is an extremely close encounter. If the comet can survive the heat and tidal forces it has been estimated that it may shine as bright or brighter than the full moon.  If it attains that brightness it could be visible during the day one degree away from the Sun.   Of course you will have to block the sun out (by standing in the shadow of a building perhaps), to view it.   The potential of this comet has been compared to the Great Comet of 1680 and the Great Comet of 2007.  It has an uncannily similar orbit to the 1680 comet which sported a 70-90 degree long tail and its head was briefly visible during daylight in December of that year.  It has been suggested that the current comet and the 1680 comet may have split from one object in the distant past.

   The Great Comet of 2007 you ask?  How did you miss that one?  Comet McNaught (C2006 P1) brightened rapidly as it approached the Sun in January 2007.  This blogger found out about it on January 4th of that year and after making 3 unsuccessful attempts to view it through mostly cloudy skies in bright twilight I finally succeeded on January 10 and captured a few photos.

1/10/2007  Comet McNaught  5 minutes after sunset



1/10/2007 Comet McNaught in bright twilight

     As winter weather goes in southeast Michigan the skies clouded over for the next week and I never saw the Great Comet of 2007 again.   Here is a link to Spaceweather.com archive from January 2007. http://spaceweather.com/archive.php?month=01&day=13&year=2007&view=view   In the middle of the page there is a photo gallery of the comet.  Perusing through the gallery you can see photos taken in midday (around page7) in which the comet is clearly visible while only 5 degrees from the Sun.    After its close approach to the Sun the comet went on to become a spectacular sight in the Southern Hemisphere as shown from page 11 onward in the above link.

   On January 10, 2007 Comet McNaught brightness was estimated at magnitude -3 or -4.  The brightness of celestial objects is measured on an inverted exponential scale., where  lower numbers indicate greater brightness.  For example an object of magnitude 3 is roughly 2.5 times brighter than a fourth magnitude object and every five steps lower on the scale equals one hundred times brighter.  For example the full moon shines at -11 magnitude, while the Sun shines -26. The 15 steps (or 3 steps of 5) of magnitude difference makes the Sun 100 x 100 x 100 or 1 million times brighter than the full moon.   The preliminary estimates of Comet ISON's predicted maximum brightness  next November range from -6 to -16.
  
    Comet experts say there really won't be any tweaking of predictions possible until August of next year. For now it's just a waiting game.   I tend to be a pessimist, that way I'm never disappointed.   I don't have time to be disappointed because I'm usually too busy disappointing others.  Therefore, I foresee the grand expectations fizzling out as the comet burns up before it's solar encounter.  I will however be ready to document the apparition if the Oort cloud visitor gets anywhere near it's predicted brightness. 
   
   To be continued......