Expert: Tom Whiting - 6/11/2009

Question
QUESTION: I live in Nelson,B.C.,Canada.January 25,2009 on a very dark night we watched with binoculars a star situated south west which was much closer than usual.It was absolutely amazing and so beautiful!It had flashing lights of every color you could imagine and round black areas of varying sizes which we thought might be craters. It was visible for 2 hours or so then moved too far away.
Can you tell us if this was a star or planet or any information at all?  
Thank you, Dian

ANSWER: Hi Dian,
Ok, first a few astronomy basics.  The human eye cannot detect
distance (or even size because we can't tell distance) with lights at night.  All we see at night is....brightness. There is no way to determine, even with binoculars or a telescope, what the distance is or what the size is. It takes professional astronomers using spectroscopes and other devices to determine distance and size.

Also, anytime you see anything that departs from a steady pinpoint
of light (which is the way we see all star-like objects, even
bright planets,  with the unaided naked eye...just a bright pinpoint)....ANY departure, then that's the atmosphere interfering
with our view.  All that violent twinkling, color changes, fading
down near the horizon, jumpyness of the object, swelling up of the object...that's all atmospheric interference.  If we lived on a planet with no atmosphere (like the moon) the stars, planets, and other objects would be steady, non-changing objects, all the way down to the horizon, then quickly just disappear below your horizon
line.

Ok, my skyglobe program tracks two bright objects on Jan 25, 2009
in the southwest (actually for everyone in the upper northern
hemisphere.  We saw the brilliant Venus set around 9 pm in the
WSW, and that was followed by Sirius, the Dog star (brightest
real star) around 1 am, just below Orion, in the SW. So, depending on your time of the night, it had to be one of those two objects.
That explains the "flashing" appearance and changing colors,
and since bright stars exhibit that effect more than planets, I'm
guessing you were looking at Sirius, the dog star around 11 pm until,
1 am.
In any case, we cannot see any features on either Venus or Sirius.
The round black areas suggest that the binoculars were not quite
in focus, so the object was a bit blobby, and with all that
sintillation (violent twinkling)...the binoculars were introducing
the effect of black areas and varying sizes.  Remember, telescopes
and binoculars also magnify ALL the defects also, of a Celestial object, including the color changes and the twinkling. Couple that with a slightly out of focus view, and that's exactly what you get.
And actually, it didn't "move away"... it simply set in the southwest, but getting dimmer and dimmer as it sank into the deeper horizon haze, which you are interpreting as...moving away, where actually it was just setting in the southwest.
(Did anyone think to look for the exact same object the following
evenings or nights at the same time?  You would have seen the same exact object....for at least a few weeks afterward.

You probably don't believe all this, but realize I've been observing
the night sky for over 50 years...with binoculars and telescopes
up to 30 inches in diameter, so I've seen all that before, many
times in fact.
So Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA USA

---------- FOLLOW-UP ----------

QUESTION: Hi Tom, thanks a lot for all the information.I certainly do believe all that you said but there are a few details that I might add to make myself a little clearer.
Judging by the time of night it must have been Sirius that we saw.The object didn't seem to move down to the horizon but went to the right of us and more upwards in orbit with all the other stars. There was no jumpiness of the object itself just the flashing of lights.I would'nt say there was swelling, it just drew closer and closer and as it did it became easier to see. The black areas were rimmed with shimmering white and the orb itself was as well.We did watch it again the next few nights but it was already further away in the exact same orbit. I also didn't tell you that it was HUGE! I know what we saw seems impossible but I will keep watching the night sky hoping to see it again sometime.
Clear skies to you too,
Dian

ANSWER: Hi Dian,
You guys weren't drinking or "other stuff"...were you?   ;-)
Stars remain in the same location relative to all the other stars,
all the time.  True, Sirius does move westward across the sky
as the Earth rotates eastward, but so do all the other stars too.

Oh, one thing I forgot to mention...if Nelson is located in a
valley betweeen two major mountain ranges, then you are also
subjected to high velocity "mountain wave air currents" as the air rolls over the first chain, and really can mess up the sky with wave after wave of clear horizontal mountain air currents, at times.
We have the same problem down in the Shenandoah Valley in eastern Virginia which also lies between 2 parallel ranges...towns in Virginia like Harrisonburg, Staunton, Lexington, and Roanoke VA, down I-81... Shenandoah Valley corridor....their sky is nearly always messy, seeing-wise, as the turbulent high altitude mountain air swirls between the 2 ranges.  It's even worse in the Rockies because of the higher elevation and thus faster moving high altitude winds.  Perhaps that was what was affecting your viewing.  But
we DO know that whatever it was, it had to be...atmospherics.
Because we know that any departure from normal...steady stars and
steady pin-points with no color or size change...is all our
atmosphere interfering with the view.  So that's what had to be
going on that night.  

(You guys also get Chinook winds too, in the wintertime, right? That violent temperature change of air can also affect the seeing drastically...so perhaps you had a Chinook wind in progress that night too)?....  Downward sloping warm air as the air
descends out of the mountains, adiabatically compressed and heated,  down onto the plains and valleys...air which raises the temperature by 20-50 degrees warmer than what you were experiencing before the Chinook wind! That would cause violent changes in a person's view
of the night sky..... Just a thought.
Clear skies,
Tom Whiting
Erie PA

FOLLOW UP:
So, did anyone that night happen to comment how the air temperature was actually increasing during the night, rather than it's normal decreasing?  If so, think Chinook wind in progress....that night.
tom

---------- FOLLOW-UP ----------

QUESTION: Hi Tom, I was hoping you wouldn't think that but NO, there was no drinking or other stuff! Yes we have mountains and as far as I know there are no Chinooks here as there are in the province of Alberta. I'm not too good at explaining myself but what we saw was definately in the same location relative to all the other stars each night and it's increible to me that the atmosphere or wind could be what caused this.Maybe I'll ever know for sure what we saw but thanks to your information, I think it might have been Sirius,the Dog star.By the way, do stars have craters on them? Well Tom, whatever it was ,it was the most beautiful thing I have ever seen and if I ever find out more about it from someone here I'll let you know.I have a new found awe and respect for space and will never feel the same way about it again.I should probably invest in a telescope eh?
Thanks so much,
Dian

Answer
Hi Dian,
No, I really thought you had a legitimate question with no drinking
involved. So, just joking.
I have seen bright stars over smokestacks or other hot chimneys
putting out hot gas that swell the pinpoint star to a basketball
size, about 2 inches in diameter at arm's length...for a while.
Huge temperature variations can cause wild changes to a pinpoint
star.

No, stars are all gaseous...so no solid surface or mountains or
craters. No liquid or solid can exist on a star (like our sun)
as they are all well above the boiling point of any liquid or
metal, even titanium and tungsten. Carbon soot is the only solid
grain that can exist in stellar atmospheres, and we call those
stars Red Carbon stars, like S Cephei, T Lyrae, V Aquilae, U
Cygni, etc. They are all very cool, small reddish stars due to the
carbon soot in their atmospheres. You can google them.

No telescopes yet...in our great observing hobby, believe it or not,
equipment (scopes) come LAST, not first. Knowledge of the night
sky comes FIRST...because, if you can't point your finger to say
the Andromeda Galaxy, double star Albireo, the Lagoon Nebula, the
Beehive star cluster (all naked eye objects in a dark sky)..if you
can't do that, how are you going to point a small field of view
telescope to them?  You can't...so your first task is to learn the
naked eye night sky.  This is not as hard as it sounds, as they
are just area's now.  (No more visualing animals or men...just areas).  So if you can learn and memorize 4 adjoining area's..
Alberta, Saskatchewan, Manitoba, and Ontario...then you can also
learn and memorize Gemini, Cancer, Leo, Virgo- 4 adjoining constellations or areas.  It's the same thing.  You have to have
this foundation first.  PLUS, what do you want to specialize in?
Deep sky objects, Lunar/Planetary, double stars, comet hunting,
nova/asteroids, etc.  (And you will specialize as there is just
too much out there!) There is a telescope out there that maximizes
EACH of these activities, otherwise, we'd all have the exact same
type of scope, wouldn't we, Eh?  But we don't. Scopes are kind of
like airplanes; all airplanes fly, but you don't send a bomber
to do a fighter's job...scopes are exactly the same way.
Observing is a learning and knowledge hobby, not a flashy visuals
hobby...so raid the library. Get a star chart and learn, self-teach
yourself...the night sky. It ain't that hard to do..takes 3-6 months.
Find a club...I would think a town the size of Nelson would have
an astronomy club; if not, do what I did...start one.
Those are the proper steps to get into our great hobby.
For more info on that, please visit our club website and punch on
"Tom Whiting's Sound Advice for the Novice" at
http://www.velocity.net/~bwhiting
Clear Skies,
Tom