Orion with an iPad – Sept 2016
I continue to find the capabilities of the iPad
camera to be quite remarkable. On the right, is an iPad picture of Orion taken early in the morning, a
few weeks ago (early September 2016).
2016 iPad
photo.
A corresponding photo from Wiki (contributor
Mouser) is also shown, on the left.
Obviously, that’s a long exposure with an excellent camera on a tracking
mount.
You can see how the iPad picked up many of the main
features of Orion, such as the belt, Betelgeuse, Bellatrix, M42 (Orion nebula),
Saiph and Rigel. A number of dimmer stars
also seem to have correspondences with the Wiki picture, though some of the
iPad points of light might be artifacts, so-called “shot noise” or other forms
of digital noise.
Note that the iPad stars are somewhat blurred – I
used a “manual” iPad app, available from the Apple app site, and I believe the
exposure time was the maximum available, a quarter second. Since the iPad was hand-held, there is
naturally some blurring.
Below is a picture of Orion that I took about the
same time last year. I have labelled the
main stars on that one, to make things more obvious. You can see Sirius in the bottom left corner, and
Orion in the center of the picture. The belt of Orion is pretty easy to
make out, as are Rigel, Betelgeuse and Bellatrix. Some of Orion's dimmer
stars, to the right and above are also apparently visible.
It’s a pretty good representation of Orion, but
this year’s photo is definitely better, especially with the nice, crisp black
background. Using the longer exposure
that the manual app allowed made for a better picture this year – the
atmospheric conditions might have been better as well (i.e. “seeing”).
2015 iPad
photo.
When you take the picture, your first reaction will probably be that
there is nothing there. To see Orion, you
have to take the photo of when the seeing is exceptionally good. The
autumn months are often the best time of year for this, as the atmosphere is
relatively dry and clear (vegetation is not very biologically active, so the
air is dry). Plus, it’s still warm enough
that atmospheric ice crystals aren’t interfering with seeing, and it is pretty
comfortable for the photographer.
After taking the picture, you have to push the image in an imaging
processing program, like GIMP or even iPad's own photo editing app. Turn
the brightness way up, the raise the contrast slowly as well. The stars will come out, like magic, though
you will want to experiment with settings, to get the best effect.
----------------------------------------------------------------------------------------------------------------------
Speaking of wiki, I will take advantage of it to give a brief overview of Orion:
·
Orion is one of the most
well-known constellations, easily visible even in a light polluted urban
environment. Most of the key stars are
second magnitude or brighter.
·
It is generally thought of as a
winter constellation in the northern hemisphere, since it is most visible in
the evening in January, when looking due south.
·
It’s pretty unmistakable, once
you know what to look for. It’s supposed
to represent the mythical hunter Orion – in any case, it is easy to connect the
dots, to see a human figure, wearing a belt.
·
It should still be recognizable
far into the future, as its brightest stars are very far away, so their proper
motion will not be very significant (they won’t drift apart, very much).
·
Betelgeuse will probably go
super-nova within the next million years or so. It’s a red giant, and they have
relatively short lifetimes. That
shouldn’t have any great impact on Earth, though it would be an interesting
sight.
·
Rigel will eventually go
super-nova too.
·
It contains the famous naked-eye
visible M42 Orion nebula, which is a stellar nursery, where stars are being
born. Stars in the associated Trapezium
are very young.
·
There are a number of other
interesting deep-sky objects in Orion, such as the Horse-head Nebula.
-----------------------------------------------------------------------------------------------------------------
Now that you have read some real science (astronomy and astrophysics), you should read some science fiction.
Kati of Terra
How about trying Kati of Terra,
the 3-novel story of a feisty young Earth woman, making her way in that big,
bad, beautiful universe out there.
The Witches’ Stones
Or, you might prefer, the trilogy
of the Witches’ Stones (they’re psychic aliens, not actual witches), which
follows the interactions of a future Earth confederation, an opposing galactic
power, and the Witches of Kordea. It
features Sarah Mackenzie, another feisty young Earth woman (they’re the most
interesting type – the novelist who wrote the books is pretty feisty, too).
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