new year's sun spots, *solar winter storm warning tonight*

last year was the year of the solar maximum
peak in the 11 year cycle of sunspot activity
this is related to the sun's magnetic field flipping
water world with fire
which means this year is...
the year after the solar maximum
and still pretty good for solar activity so far.

took some relatively high power images of sun spots on new year's day:

there was some interesting activity just visible on the other edge:

the sun's surface rotates with a period of approximately 28 days when viewed from earth...
so here it is a few days later on 1/5/14 facing us:
this was a big one which could be easily seen without magnification (looking thru filter)

on 1/7/14 a coronal mass ejection was launched from this spot aimed right at us
as a result, tonight we're going to get hit by plasma consisting of charged protons, electrons, alpha particles and such...
which means major aurora activity tonight at the poles
there's a slight chance that you may see some activity if you live moderately far north
so take a look outside
you may see some strange lights

for more on this check out
http://www.spaceweather.com/

first light from new home: Christmas Jupiter

haven't imaged in about 6 months due to move/move/remodel... Jupiter is just past opposition now and should be in excellent position for viewing for the rest of January. Here's my first light image with a new camera from new location, Jupiter on Xmas night:

unfortunately, the seeing was terrible, amazed i was able to pull anything out at all. this is an animation of two shots taken about 30 minutes apart. shows the great red spot (lower left) just rotating into view.
here it is the next night (again terrible seeing)

you can see the great red spot lower left, Io's shadow upper mid, and a hint of Io just above and to the right of it's shadow.

cheers

Crab Nebula Expansion

Here are 4 images over 6 years showing the expansion of the crab nebula, a supernova remnant. 

Extrapolating the expansion back to time 0 gets close to the observed 1054 AD supernova.  Note the bluish pulsar wind lower left, seems to be moving faster than the red filaments

4th of july supernova revisited-crab pulsar wind

On July 4th 1054 AD, astrologers observed a bright blue square in the sky near the sun at dawn. it was visible during the day for 3 weeks and at night for 2 years. 700 years later, the Crab Nebula became the first object in Charles Messier's famous catalog:

 What makes the crab nebula glow? The bluer of the two central stars is a dense neutron star,
the remnant of the original star that went supernova on the 4th, spinning at 30 revolutions per second. A strong magnetic field associated with the spinning star accelerates electrons in the surrounding space to relativistic speeds. Collisions between the electrons and surrounding matter give off very high energy photons. Rather than the central star, it is the photons from these collisions (EDIT: my physics buddies have informed me that it is the acceleration itself that causes the high energy photon emissions, no collisions needed)  that cause the gas in the surrounding filaments to glow like fluorescent lights.
pulsar wind:

enamored with the concept of the pulsar wind, i attempted to capture it with a filter which blocks the emission line signal, giving only the broad band pulsar wind. a quick look at the crab nebula spectrum shows a wide region devoid of emission lines

after making a few calls, trying to get a nice wide filter in this region, i found a custom filter would cost more than my camera. so i went with a narrow filter in the region that was available in order to capture this broad band signal. i had hoped to capture some motion with the filter, but the broad band emissions were so weak with the narrow filter, that i was unable to get enough detail on any given night (or two) to convincingly demonstrate motion.

in any event, the combined stack gives a nice view of the pulsar wind without the pesky emission lines obscuring the view. i find the blink fascinating, tracing the swirls, wisps and arcs of broad band emission, and then following them into the combined image.

here's my 2011 crab nebula animation showing some motion in the broad band.

happy 4th

-bill w

sun and moon for summer solstice

 this is the year of the solar maximum--maximum sunspot activity in the 11 year solar cycle.
10 pm pacific today 6/20/13 is the summer solstice.
what better time for solar images?

here are two images of the sun taken at about the same time with different filters. 

first up, the sun in "white light", using a filter that blocks out 99.999% of the sun's light
you can see a few dark sun spots (which are still blindingly bright without filters), a slightly granular appearance, and a few lighter areas.  this is the photosphere which is basically the surface of the sun.
the second image is the sun imaged with a hydrogen alpha filter that allows all of the sun's light at a specific frequency, which corresponds to absorption and emission of light due to hydrogen.  this shows the chromosphere, a thin layer above the photosphere dominated by hydrogen emissions.  it usually can't be seen as it is overwhelmed by bright emissions from the photosphere.  the hydrogen alpha filter allows us to see the chromosphere's wavy filaments and prominences.
you can still see hints of sunspots, but there's much more going on. 

next i colorized the image and then lightened it dramatically to show the faint prominences (things shooting off the disk around the rim).  since this overwhelmed the central detail, the original darker image was superimposed to maintain some of the surface detail.  bear in mind the prominences seen at the edge are much more faint than the central detail.  the dark line upper right across the face is called a filament.  it's basically the same phenomenon as a prominence, but coming off the surface towards the viewer rather than occurring at the edge. 

last up is the full moon, which happens to be the same size as the sun, which is convenient for things like eclipses
and finding something to do with your solar rig at night. 
this was taken with the same scope and camera as the first image, leaving off the filter. 
why do astrophotographers rarely image the full moon? 
the sunlight is shining straight down on the face which washes out the detail of landscape. 

the sharp eyed viewer will note better contrast at the extreme bottom portion of the image
where a few shadows are cast enhancing detail in this moon that was 6 hours away from full. 

have a good summer

whw

Mother of a Prom

interrupting the planetary overview.

lot's of solar activity on mother's day

here's a close up with the bright disk blocked out to emphasize the faint prominence:

still working on full disk versions

Mars

will skip earth and the moon for now
and move on to the 4th planet from the sun
Mars aka the red planet

mars is a small planet, about half the size of the earth
with mass equivalent to mercury

Mars is the only planet who's surface detail can be seen from the earth
(detail seen on other planets is related to clouds)

The red-orange appearance of the Martian surface is caused by iron oxide (basically rust) in the soil
as well as a reddening effect due to dust in the atmosphere.
many areas have blue tinted rocks altering the surface color.

the squiggly line upper right of center is a giant dust storm on the surface.
the white dot upper left is a melting polar cap
made of carbon dioxide and some water ice.

the polar caps change with the martian season
and can be followed in the telescope when mars is in view:

the orbit of mars is relatively close to the earth's
as a result detail in mars is only visible through telescopes
as the earth approaches mars in it's orbit
this occurs every 20 months (approximately)
and lasts for 4 to 6 weeks, with the best viewing for only 2 weeks
so folks get excited when this occurs
the next will be in april 2014 :(

this of course is the time when mars goes into retrograde motion
as the earth passes mars
(which we all learned about in earth science and promptly forgot)
http://en.wikipedia.org/wiki/Mars#Astronomy_on_Mars

more stuff

mars has two moons
Phobos and Deimos
Phobos is in a decaying orbit, slowly falling to the surface
which brings up an interesting tangent

classic example of the Roche limit:
as Phobos descends to the surface of mars, the gravitational force acting on it will increase.
gravitational strength varies with distance.
so at some point during the descent the gravitational pull on the near side of the moon will by *much* greater than the pull on the far side.
stronger than the force holding the moon together.
the net result is that the moon will break apart, potentially leaving a ring on the way down.
this point is known as the Roche limit

an extreme example of this occurs near black holes where matter is torn apart in strings pointing towards the black hole
a process known as spaghettification
which is fun to say
https://en.wikipedia.org/wiki/Spaghettification

lastly, the sci-fi book red mars

http://www.amazon.com/Red-Mars-Trilogy-Stanley-Robinson/dp/0553560735
considered "hard" sci-fi
gives what seems like a very real depiction of how mars could be colonized
has a feel similar to 50's sci fi accurately predicting space flight and moon walks
with lots of detail on martian planetology, whether, etc
warning:
very dark book, heavy on planetology, weak on biology

whw