March 26, 2017

NGC 5466 (Mar. 25, 2017)


This globular cluster is about 52,000 light years away and appears in the constellation Bootes.  As globs go, this one is sparse.

A galaxy on the lower left (northwest) of the image is PGC 1840894, magnitude 17.70.  The larger galaxy at lower right is PGC 1835025, magnitude 17.37.

The most interesting thing (I thought) about this globular is that a galaxy glows through it.  At the lower right of the cluster, one glowing object is a smudge instead of a star.  It is about 25% of the way from the center of the cluster to PGC 1835025.  It is very faint.  I have no idea if it has a name. A Hubble shot of NGC 5466 (lower left in that version) shows that this smudge is actually a spiral galaxy in the far distant background.  Interestingly, the Hubble image also shows several other galaxies shining through that are not visible in my data.  You can see them if you zoom in and pan around.

This is 8x480" with the SXVF-H9 through the CFF Classical Cassegrain at f/7.93.

NGC 4088 (March 25, 2017)


This galaxy is between 40 and 60 million light years distant and appears in the constellation Ursa Major.  It has an unusual shape (one arm seems to be pointing the wrong way) and so is listed in the Arp catalog as well (#018).  It is probably a member of the same group as M109.  This is 9x900" with the SXVF-H9 through the CFF 290 Classical Cassegrain at f/7.93.  The galaxy to the lower right (southwest, actually) is PGC 38369.  North is left in this image.

February 17, 2017

North America Nebula, June 2016

Here is the North America Nebula in Cygnus, from DSW data collected in June of 2016.  This is just H-α data, 18x1200" worth through a Takahashi 106-FSQ with a QSI683wsg.

February 7, 2017

NGC 2371 & 2372, a Planetary Nebula in Gemini (Jan. 2017)


Here is a planetary nebula that sits just south of Castor and Pollux, the two bright stars in the heads of Gemini.  The nebula looks a bit like taffy candy.  The Taffy Nebula?

The data for this image was gathered through Astronomik 6nm-wide narrowband filters focused on the emission lines of Hydrogen alpha (H-α) and OIII.  The H-α filter may also pick up some NII emission at 658.4 nm.  Two hours of data (8x900") were collected through each filter.  The two data sets were combined with a synthetic green channel to create an RGB.  The color of the image matches closely the cyan of the OIII emission, which predominates the data, but the image preserves also the H-α [+NII] emission, and particularly the jets coming from the central star.  I have included the separate monochrome data from the two sets below.  The nebula's central star is about magnitude 14.8.

This image was taken through the CFF 290 Classical Cassegrain at f/7.93, with the SXVF-H9 camera.

Here is a link to a Hubble image of the nebula.

Here is the OIII:

Here is the Hα:

And here is an inverted and stretched OIII version showing the looping of the jets back around to form the taffy wrapper pulls, or, at least, that's what it looks like to me.  An interesting paper discussing the nebula's structure is here: https://arxiv.org/ftp/arxiv/papers/1206/1206.1902.pdf.



January 28, 2017

M51 (May 2016)


This is another set of Luminance subs from DSW, 24x900" plus 1x1200".  Of course, I've imaged this before, but this is the deepest data I've processed.  This image is about 80% of full size because I wanted it to sort-of fit on the screen.  Notice the numerous little galaxies in the background, and some galaxy clusters.

January 16, 2017

Leo Trio (April 2015)


I am just getting around to processing this 8 hours of luminance data from DSW in New Mexico.  As you can see, the skies there are great and equipment superb.  The telescope is a Tak FSQ 106.  The 8300-chip camera leaves slight blooms on stars that mimic diffraction spikes, an aesthetically pleasing failure of the camera's anti-blooming gate.

This is a great part of the sky, and this image allows one to fall into it several hundred million light years.  The big galaxies are about 35 million light years away (give or take 10 million). The smallest galaxies are hundreds of millions of light years distant.  See if you can spot clumps of those little dust motes in the distant background.

January 3, 2017

Horsehead Nebula (Jan. 2017)


OK, another Horsehead, but I had a lot of fun taking it.  This is 7x600" with the SXVF-H9 through the CCF290 Classical Cassegrain at f/7.93.

November 1, 2016

NGC 604 in M33, Reprise (October 2016)


Here is NGC 604 again with more data, now with 40x600" instead of just 12x600".  Everything else is the same about the setup: it is the CFF 290 Classical Cassegrain operating at f/7.93 (A-P CCDT67 Telecompressor).  The camera is the SXVF-H9 through an Astronomik CLS filter.  The larger data set gives a better signal-to-noise ratio, and the dimmer parts of the image are brighter, with more definition.  The image reveals the mottled, star-spotted arms of a galaxy.

October 25, 2016

Tadpoles and a Double Star in a Tadpole in IC410 (Oct. 2016


This is a closeup of a famous nebular formation in IC410 in the constellation Auriga.  The whole area is filled with glowing hydrogen, but the two brightest parts of the area are shown here, the two tadpoles.  These are caused by energy rushing up against clumps of gas; the collision makes the gas glow.  This is the highest resolution image of the area I've ever taken.  Specifically, I never saw that the second (lower) star of the two in the hood on the right is actually a double star.  Probably most telescopes would show it visually at high magnification, but in a long exposure, only a very long focal length and quite good seeing would show the star's double nature.  I was happy to see it.  This is just 5x600" with the CFF290 Classical Cassegrain through the SXVF-H9 at f/7.93.

NGC 604 in M33 (October 2016)


Here is a grand nebula in another galaxy.  Galaxy M33 is about 2.5 million light years away, about as far as the Andromeda Galaxy.  That's not very far for a galaxy.  M33 is our near neighbor.  This nebula is a huge cloud of glowing hydrogen from which stars are forming.  In the upper right third of the image you can see stars in a curve of one of M33's spiral arms.  These stars are some of the brightest stars in M33. You are literally seeing here light from individual stars and stellar systems in another galaxy. Other nebulae also dot the landscape.

This image is just 12x600" through the CFF290 Classical Cassegrain at f/7.93, with the SXVF-H9 camera.