Thursday, October 23, 2014

eclipse preview and a monster spot

as usual, the sun has upstaged the moon, producing the largest sunspot folks have seen in years at the same time as the partial solar eclipse.  it's so big folks are simply referring to it as the monster.  larger than jupiter and easily visible without magnification (eclipse glasses only).
here's a section of it:

and here's the full disk in hydrogen alpha mid way through the partial eclipse:

more to follow...

Sunday, October 19, 2014

solar surface animation, eclipse alert 10/23/14

OK first up
there will be a solar eclipse visible from the US on thursday 10/23/14.
http://shadowandsubstance.com/#Partial
needless to say, as it's only a partial eclipse, the sun will still be blindingly bright.
protective eye-wear or projection is a must for viewing.

not much happened in my full disk Ha animations.
close-ups of prominences however gave interesting movements.
so here are some close ups of the disk surface.
not quite as dramatic as a prominence lifting off, but still interesting.
first, here's the full field (click on image for full size):

high contrast grey-scale



here's a circular filament around an active region:

here are what look like classic magnetic field lines from one sun spot to another:

a filament arching off the surface:

eruptions around a sun spot, which, i guess is why they're called "active regions":


imaging details:
7/5/14 newport beach, ca
DMK 51, 2.5x Powermate, Lunt 60 PT B1200
2 hours of imaging at ~12 fps every other minute
best 300 frames every minute
7.8 ms exposure
the images were spoiled by dust on the sensor
finally salvaged them by creating artificial flats
though you can still see some faint shadows of dust spots in the animations
(right side of last)

Monday, October 6, 2014

Saturn 2014

forgot to send out this year's best shot:
getting some nice color in the bands
a hint of the north polar cloud, but no hexagon
can see Cassini's division and the maybe Encke minimum

the images are taken by using a video camera, stacking thousands of short long exposures
allowing processing software to select the images least distorted by seeing
stacking thousands of images in this way gives a much more sharp image

in theory one can upsample the video by 2x to get better magnification
so i decided to do a test, comparing and upsampled image
with an image using a 2.5x barlow to give more magnification
but requiring longer exposure.

which will be better?
larger magnification with longer exposure
or shorter exposure eliminating seeing effects?

2.5x barlow:

upsampled 2x:

compare the Encke minimum and colored bands
close, but i think the barlow wins
though the seeing wasn't really sufficient for either

Sunday, September 21, 2014

saturn overview

Saturn
6th planet from the sun, second largest after jupiter
a gas giant

it has a slight yellowish color due to ammonia in the upper atmosphere
with faint bands (much less dramatic than jupiter's)
and...

IT HAS RINGS!


first view of saturn through a telescope:
unknowingly, i pointed the scope at a bright "star" rising in the east
and was shocked to see it had rings...
a shudder and a concrete sense that there really is more out there than we know.
there's something about the rings and the shadow they cast over the sphere that makes it appear much more like a perfect 3-dimensional structure than a simple disk. 




the gap in the rings is called the Cassini division.
the darker band outside the cassini division is called the Encke minimum.
there's a near mythical gap outside of that called the Encke division.
that is only visible from earth with under excellent seeing conditions with high quality optics.

the angle of the rings varies from year to year as saturn makes its 29.5 year orbit around the sun.
in 2002 they were maximally tilted with the south pole facing us
(about the time i bought my largest scope)

here's one of my earliest shots from 2004:


in 2009, they were edge-on
though many find this the worst time to view saturn
i found the iconic line made an interesting image:

the rings are now opening again
peaking in June 2017 with the best view of the rings and the north pole of the planet (this event will sell lots of telescopes ;)

there's something special about the north pole:
the dark patch at the north pole is actually hexagonal!
it is a persistent cloud pattern, similar to jupiter's great red spot
santa's helpers must be more mischievous on saturn
i've yet to see or image it, but as the north pole continues to tilt
towards us i'm hoping to catch it


saturn has 150 moons and counting
the largest, titan, is larger than mercury and contains it's own atmosphere as well as hydrocarbon lakes.
titan casting shadow on saturn's surface:



9 or 10 can be seen thru an amateur telescope


enceladus is notable for salt water geysers which contribute to saturn's rings

more on saturn:
http://solarsystem.nasa.gov/planets/profile.cfm?Object=Saturn
http://www.nakedeyeplanets.com/saturn-orbit.htm
http://www.astronomycast.com/2007/10/episode-59-saturn/
http://www.astronomycast.com/2014/05/ep-344-the-rings-of-saturn/
http://www.astronomycast.com/2007/11/episode-61-saturns-moons/
http://en.wikipedia.org/wiki/Saturn%27s_hexagon

Saturday, September 6, 2014

M 24, it's full of stars

"my God it's full of stars"
-Dave Bowman's final words prior to entering the monolith in 2001: a space odyssey.  contrary to my recollection, the line occurred only in the book version, not the movie, but was grafted into the movie as a flashback in the opening of 2010.  

Messier object 24, a/k/a the sagittarius star cloud,  isn't really a star cluster, it's just a bright patch of stars in the milky way surrounded by dust.  it can be thought of as a hole in the dust, allowing us to see much deeper towards the center of our galaxy.  (no frank, you can't see the black hole).  The bright patch can be seen with the naked eye in skies dark enough to see the milky way as a bright patch above sagittarius


the patch of red, suggested there was some glowing hydrogen in the surrounding gas, so i decided to shoot it with an Ha filter:


Here's a combined view:


interestingly i see an Ha wall along the upper right margin of the star cloud
that is more evident in the HaRGB than the Ha itself.

if it weren't full of stars it would look like this:



Lastly here's a close up of the open cluster in the upper left portion of the star cloud i shot a few years ago:




-bill w

image details:

FS 60c @ 254 mm 5.23"/px full size
field approximately 2.5x3.5 degrees
Hutech IDAS, Chroma Loglow, Astrodon 5nm Ha filters
SX H9C, ASA DDM 60 unguided
4 panel mosiac composed of approximately 17 5 minute subs RGB
15 5 minutes subs Ha
7/21-8/17/2014
newport beach, ca

more than you wanted to know about 2001:
http://www.filmsite.org/twot.html
http://c2.com/cgi/wiki?MyGodItsFullOfStars

Thursday, September 4, 2014

Delta Aquilae is 50 light years away

Aquila, the eagle, is a summer constellation. 
It can be found here in the summer evenings section:

It’s brightest star, alpha aquilae, a/k/a altair, forms one of the corners of the summer triangle.  A huge right triangle seen overhead during summer nights. 
Delta aquilae is at the center of the eagle.  At visual magnitude 3.36 it can be seen with the naked eye in good viewing conditions.



It is 50 light years away. 

Einstein’s theory of special relativity.  Basically states that the speed of light is the same for all observers.  Consider a space ship moving away from us at half the speed of light.  We shine a bright pulse of light into space.  After a year the light has traveled one light year away from us, while the space ship has traveled half a light year.  The pulse of light is half a light year from the ship.  So if the light has only traveled half a light year from the ship, how can its speed relative to the ship be the same?  Speed=distance/time.  So the solution is that the ship has only experienced half the time we have on earth—time has slowed down. 

Consider a photon leaving delta aquilae 50 years ago.  Some of us have experienced 50 years waiting for its arrival today.  But the photon, traveling AT the speed of light experienced no time at all. 

Something to think about for this day.  

Imaging details.
FS 60c @ 254 mm 5.23"/px full size
Chroma Loglow filter
SX H9C, ASA DDM 60 unguided
13 5 minutes, 24x30s, 24x3s
"diffraction spikes" added in processing for emphasis
newport beach, ca

Wednesday, August 20, 2014

Leo Galaxy Cluster aka Abell 1367: Part 3 quasars and cosomology

Caught a number of background quasars in the field of Abell 1367.

quasars (quasi-stellar radio sources)
look like faint blue stars
but they have *very* high red-shifts
which made them somewhat of a mystery

turns out they are actually extremely distant galaxies
with black holes that are actively feeding on matter
generating massive amounts of light.
though light cannot escape the black holes,
energy is generated just outside the event horizon
by massive gravitational stresses and friction acting on the incoming material.

the most distant quasar in the image
(blue dot just below the S in QSO lower left)
has a red shift (Z) of 3.36: 

recall that the redshift of the galaxy cluster 330 million light years distant was 2.3% or .023
the QSO's red shift is 3.36 or 336%!

so how far away is it?
well here's where things get *relatively* slippery
the universe is expanding
it's taken light a really long time to reach us from this object
do we want to know how far away it is now or how far away it was when the light left the galaxy?
when it left the galaxy, our planet, solar system and sun didn't exist.
now, due to the expansion of the universe, the galaxy is moving away from us faster than the speed of light
it's current distance can never be observed

dirty cosmology trick:
nothing can move through space faster than the speed of light
but the universe itself can expand faster than the speed of light
(my head hurts)

the commonly used figure is
light travel time
which is neither where it is now, nor where it was when it emitted the light
but a measure of how long it took the photons to reach us

it gets even worse:
redshift versus distance is not linear for large distances
so in order to calculate the distance
theoretical models with various parameters including the shape of the universe!
have to be used
best estimates for the parameters change over time

...so by one of the more commonly used estimates*, this one is
11.8 billion light years away
the big bang happened 13.7 billion years ago
the universe was a lot smaller place when light left this object

here's another small crop from the center of the image
including the Ha emitting galaxy from last time
with 3 quasars (distance in billions of light years):



interesting cosmological explanations (laymen's terms):

life the universe and everything
(be sure to mouse over the answer)

Ned Wright's FAQ on cosmology and the big bang

*Ned Wright's Cosmology Calculator