M67,Twice (12-2012 to 2-2013)

 Full resolution image here.

There is a time during the night in December through February when bright targets are not too plentiful.  This one, M67, is one of the few.  In between working on dimmer targets, I took some frames of M67.  We see M67 in the constellation Cancer.

M67 is an open cluster of stars that is between 2,500 and 3,000 light years away.  Its age is between 3.5 and 5 billion years.  Our Sun is about 5 billion years old, we believe.  The Sun and M67 are moving in the same general direction through space in our Milky Way Galaxy.  Some have speculated that our Sun was once a member of the cluster, though later studies (such as here) make this seem unlikely.

Regardless, M67 is a beautiful open cluster in a telescope.  No image really captures the beauty of the stars, but these remind me of the cluster.

The first was taken with the AT111EDT, a refractor.  The spikes were placed on the stars with software.  I think they are subtle and give the stars a bit of sparkle.  That image leads the three because it most nicely frames the cluster.  Here is the same image without the spikes:

Full resolution image here.

And here is one taken through the Orion 254mm f/4.7 Newtonian.  In this image, the spikes are part of the star shapes created by the telescope.  The color for the Newtonian image comes from the Palomar and AAO Digital Sky Survey II, publicly available on the web.  Thanks to Dick Locke for generously sharing a color-balanced sample image.

Full resolution image here.

Telescope: Astro-Tech AT111EDT and William Optics P-FLAT4 (eff. at f/5.6)
Camera and Exposure: SXVF-H9C; L (15x180"), R (6x300"), G (7x300"), B (7x300"); Alnitak Flat-man flats
Filter: Astronomik CLS and RGB filters
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX 

Telescope: Orion 254mm f/4.7 Newtonian and RCC I
Camera and Exposure: SXVF-H9 (L: 9x240"), T-shirt flats
Filter: IDAS LPS-P2
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX

NGC 1999, the Keyhole Nebula (Dec. 12, 2012)

This is NGC 1999, the Keyhole Nebula.  It is a reflection nebula lit by the star on the right edge of the lower part of the keyhole.  The nebula is so bright there that it is difficult to see the star separately from the nebula.

The interesting thing about the Keyhole Nebula is that it is actually a hole.  Many dark spots seen against a brighter nebular background are cold clouds of gas and dust.  Not so the Keyhole, apparently.  The keyhole feature appears actually to be a hole.  Deep images with a variety of infrared scopes (reported here) show that in the keyhold feature there lurks ... nothing.  What blasted a hole through this patch of otherwise brightly lit cloud?  That is a mystery, but the area is full of young stars just beginning stellar life.  Perhaps one of them blasted a tunnel right through.

Mine is not a deep image.  Surrounding the blue reflection nebula is a lot more gas and dust that is not lit up so brightly with reflected light.  Some more interesting objects my image only begins to show are also brighter in other pictures of the region.  You can see some of them in Adam Block's image, here, taken with a much larger scope from the top of a very dark mountain.  In my image you can see just a hint of these other things in the reddish background and in the red glowing objects just to the right of the Keyhole Nebula.

Telescope: Orion 254mm f/4.7 Newtonian and RCC I
Camera and Exposure: SXVF-H9 (R: 9x240"; B: 10x240" (synthetic green)), T-shirt flats
Filter: Astronomik RB, IDAS-LPS2
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX

M1 (Dec. 12, 2012)

Link to full resolution image here.

In 1054 A.D. , Chinese astronomers noted a new star in the sky.  It shone so brightly that folks could see it in the daytime.  But the star was temporary.  In fact, it was not a new star at all but an old star that exploded.  This nebula is the result of that explosion.  M1 is a supernova remnant.  It is one of the coolest deep sky objects in the heavens.

Why so cool?  Well, first, this is one of the few deep sky objects whose origin was observed by human beings, and it's been growing ever since.  Most objects in the sky change very slowly by our time scale, but not this one.  In fact, some amateur astronomers have observed changes in M1 in their own images over time.

Second, M1 is not just a supernova remnant.  It is the home of what is left of the star that exploded.  The core of the supernova did not have enough mass to become a black hole, so it stopped just short of that and became a neutron star.  Within it, gravity's power has overcome the forces that create space within atoms, crushing the elements away.  What is left is a ball of neutrons only 15-18 miles wide that contains more mass than the Sun!  Pretty heavy stuff!

But there is more.  The neutron star and its interactions with its immediate environment produce more than just visible light.  Radio waves, x-rays, and gamma rays all stream out of the center of M1.  See NASA's combined optical and x-ray image of the center of M1 here.  The neutron star's intense radiation causes this to happen.

Even more remarkably, the neutron star is spinning very quickly.  It's strong electromagnetic field concentrates the radio waves into pulses that tick like a clock in space.  When astronomers first heard it, its regularity suggested that astronomers were receiving a signal from aliens.  But theorists later determined how a neutron star could produce such pulses.  We call such a spinning neutron star a pulsar.

The pulsar itself is visible in this image.  At the center of the nebula are two stars, easily visible next to each other.  The pulsar is the dimmer of the two, on the right.  We may not have a picture of a black hole yet, but we have images of the next closest thing.  How cool is that?

This image is a combination of (1) a stack of frames taken through an H-alpha filter with (2) a short color image I took a year ago through the same telescope.  I have simply slapped the color over the H-alpha image.  Here is the H-alpha alone:

Here is the capture data for the H-alpha image:
Telescope: Orion 254mm f/4.7 Newtonian and RCC I
Camera and Exposure: SXVF-H9 (H-alpha: 10x900"), T-shirt flats
Filter: Astronomik 12nm Ha
Guiding: SX Lodestar and SX OAG
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Registar, Photoshop CS3
Location: The Woodlands, TX

The color data is described here.

NGC 6910 (5-3-2011)

This lovely cluster illustrates the work I did on the telescope two days ago.  Previously, my stars were out of round, and I wasn't sure why.  I made three changes that day:  (1) I squared the focuser with the tube.  This is something I should have done earlier.  (2) I flocked the tube across from the focuser.  I was worried that light from the back of the secondary mirror was bouncing around inside the tube.  That will stop it.  (3) I blackened the back and sides of the secondary mirror with flat black paint.  I had an epiphany after I flocked the tube.  I looked down the eyepiece tube and saw ... the reflection off the side of the secondary, shining brightly right into the eyepiece.  I immediately knew the source of my out-of-round stars.  Time to get out the paint.  Now the stars are round.  They are beautiful.  The scope is doing what it's supposed to do now.

This picturesque cluster is just north of Sadr, or Gamma Cygni.  I was going to image something else, in the south, but my guiding was off because cables were catching on the mount.  Anyway, it was about 4 am, and I was too tired to diagnose the problem (I figured it out the next morning).  So, I thought, I'll try something near the zenith that I can actually catch in an hour.  An open cluster!  Sure.  Well, I caught the cluster, but this cluster is surrounded by nebulosity (of course, next to Sadr).  The time was too short to catch much of the nebulosity.  I guess an hour was too short.  I don't make my best decisions at 4 am.

Telescope: Orion 10" f/4.7 Newtonian
Camera & Exposure: SXVF-H9C, 13x5'
Coma Corrector: Baader RCC I
Filter: IDAS-LPS2
Guiding: Orion Deluxe OAG, Meade DSI Pro, PHD
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX

Here is a small gray-scale showing some of the nebulosity.

M101 (5-3-2011)

I've imaged this mammoth galaxy before, here.  But at only, roughly, 23 million light years away and stretching approximately 170,000 light years from side to side, this face-on spiral giant is always a welcome sight.  This is partly why I wanted to use the 10": the scope is big enough to hint at galactic details.  M101 is always a challenging target, though.  The dynamic range is massive.  The galaxy in fact has other spiral arms that I have not pictured here.  Because the image was taken from the suburbs, light pollution washes out the fainter parts.  Just for comparison, I have included below a version with the light pollution left in.  Also, this is just 14x10', not enough time to pick up these fainter portions even if I was at a darker site.  Even my earlier image of M101 is a bit deeper.  It was over 50% longer exposure time from the same site with the same camera at about the same focal ratio.

Telescope: Orion 10" f/4.7 Newtonian
Camera & Exposure: SXVF-H9C, 14x10'
Coma Corrector: Baader RCC I
Filter: IDAS-LPS2
Guiding: Orion Deluxe OAG, Meade DSI Pro, PHD
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX