Saturday, July 30, 2011

M27 - NGC 6853 - The Dumbbell Nebula

M27 - Dumbbell Nebula
It started all with a cloudy night, where I was taken glimpses of stars between cloud and cloud, to determine the quality of my new optical setup.  I was not planning on an observing night but sometime after 12:30 AM, the clouds stopped going by and the night sky opened up.   Like a good astronomer, I decided to work on some imaging for a science project, I am currently working on.    As the morning hours went by and I was about done with my imaging for the night, I looked at my planetarium software and see the label, M27 not far from my current position.  

M27 in false colors
Well it happens that M27, also known as the Dumbbell Nebula is a beautiful planetary nebula in the constellation Vulpelcula. It signals the end of the life of a star. In its center there is a star remnant called a white dwarf. The expanding material that we see spans about 3 ligth years across. The nebula itself is 1,360 light years away.
The images were taken last night from VAO, 3x60 second exposures on the luminance filter, binned 2x2 with an Orion Parsec Monochromatic camera with my LX200 ACF 12" telescope at aprrox. f/6.3

Monday, July 25, 2011

Distances in Astronomy

© Billy Vazquez 2011
We look at the night sky and everything seems equally distant from our point of view.   The reality is quite different.  Astronomers study celestial objects and can determine their distance from Earth.   To the right an image taken from VAO(Vazquez Astronomical Observatory). The first one to the right is of a distant galaxy named Mark876.  But where is the galaxy in that image?  Well is very small and point like.  Just like any other star in that image. That is because this galaxy is so far away from us that it looks as just another star in the sky.  What we see, is its bright nucleus at a distance of  476.5 Mpc.  A parsec is 30,857 billion kilometers.
© Billy Vazquez 2011

The second image reveals M101 also known as the Pinwheel galaxy.   It is a spiral galaxy and there is no mistake, we can tell by the look of it that it is indeed a galaxy.  How far is it?  It is merely 3.4 Mpc away.  That is just 104,739,957,746,478,873,239 km away from Earth.  Definitely closer than Mrk 876.  How do we know the galaxy is so far away?  Lucky for us there are stars in the universe called Cepheids, which change brightness periodically.  Using their change of brightness we can determine their distance to Earth.  Galaxies like M101 are beautiful sights for astrophotographers.

© Billy Vazquez 2011

Last but not least, I present M13 the globular cluster in our own Mily Way Galaxy.   How far is it?  It is just shy of 236,513,210,000,000 km from Earth.   The light from the stars of M13 as seen today is about 25,000 years old.  Therefore as we look into the night sky we look into the distant past of the Universe.  It makes you wonder how so many stars got all clumped together and they still navigate through our Galaxy as a single unit.

Monday, July 18, 2011

Green Bank Radio Astronomy at NRAO

Credits: 2011 Billy Vazquez, GBT @ West Virginia , NRAO
Radio Astronomy refers to the study of the electromagnetic spectrum between wavelengths of 0.3 mm to 30 m.  This covers frequencies between 1 THz to 10 MHz.    The largest Single Dish Radio Telescope on the continental US is the Green Bank Telescope in West Virginia.  It is only surpassed in dish area by the Arecibo Radio Telescope in Arecibo, Puerto Rico.  Arecibo has greater sensitivity, but operates only between 50 Mhz to 10 Ghz.  It is also restricted to plus/minus 20 degrees from its current latitude of 18 degrees, as the dish is non-steerable.  Green Bank can operate at higher frequencies above 100 Ghz and it can fully track any object in the sky above 5 degrees above the horizon.

Credits: 2006  M. Blanton , D.  Hogg and the SDSS
To the right two images of the same galaxy, NGC 5668.  It is a spiral galaxy as you can see from the optical image to the right with a clear bright core.   Also to the right the radio spectral image of the same galaxy at 1.4 Ghz.   This particular frequency is very useful for astronomers as it gives us lots of information about the observed celestial object.  This line, also known as the 21 cm line, tells us the radial velocity at which this galaxy is receding away from us.   In this case roughly about 1575 km/s away from us.  The graph also tells us that there is rotation of hydrogen gas as can be shown from the double horn feature.   Some of the gas is blue-shifted towards us , while some is red-shifted towards us at about a rate of 50 km/s.

The power of radio astronomy lets us determine many properties of celestial objects and it will only get more interesting in the future as new and improved facilities like the EVLA  and ALMA start producing new science.

Monday, July 4, 2011

M33 - The Triangulum Galaxy

M33- The Triangulum GalaxyLRGB composition
2600 second total exposure time, false colors
300mm, f/6.3, Orion Parsec 5.4 micron, 2x2 bin
At an estimated distance of about 900 kpc (give or take some kpc), this galaxy is part of the Local Group.  The Local Group is a collection of galaxies which also contains the MilkyWay and Andromeda among other small dwarf spheroidal galaxies. M33 as it is also known in the Messier Catalog is a spiral galaxy with an approximate mass of 50 billion solar masses and roughly 40 billion stars!  Its apparent magnitude is 5.72 which makes it an ideal extended object to test the darkness level of your observing site.   If you can see M33 with averted vision then you know you are in a pretty good site for astronomical observations.

The image to your right was taken on July 4th, 2011 from VAO in Webster, NY.   It is rendered in false colors to enhance the contrast areas.   I took 3x300 seconds exposures through a luminance filter with IR blocking. 3x200 second exposures through RGB filters, then reduced and combined.

M33- The Triangulum GalaxyLRGB composition
2600 second total exposure time, monochromatic
300mm, f/6.3, Orion Parsec 5.4 micron, 2x2 bin
For those of us who like monochromatic images, here is the combined image before processing with false colors. VAO is now ready for some science runs.  That includes transiting exoplanet exploration and AGN(active galactic nuclei) imaging.  Stay tuned for some more science!

Clear Skies!

Saturday, July 2, 2011

NGC 7635 - The Bubble Nebula

NGC 7635 - The Bubble Nebula
3x1000sec exposures/each - Ha/R/G/B filters
© Billy Vazquez @ VAO Webster, NY 6/1/2011
The image to your right is NGC 7635, also known as the Bubble Nebula.  It is a combined image through the Ha, R, G and B filters.  Each filter frame is the combination of three 1000 seconds exposures for a total exposed time per filter frame of 50 minutes and a grand total of 3.33 hours of exposure time to create the beautiful image you see to your right.  The image was processed as per the usual data reduction pipeline of dark and flat fields. 

The Bubble Nebula is found in the Cassiopeia constellation, relatively close in the night sky to another interesting object, open cluster Messier 52.   The bubble is created by the stellar winds of a massive hot star SAO 20575.  SAO 20575 is an O type star, which is about 10-20 more massive than the sun  and about 4 times bigger.  It is located 11,000 light years away from us and the bubble spans about 10 light years across. 

NGC 7635 - The Bubble Nebula
50  minute Ha exposure
© Billy Vazquez @ VAO Webster, NY 6/1/2011
Although the color image is evocative, I like to present to you what the Ha channel frame looks like without any editing and spanning the whole view of the CCD.   The monochromatic image gives the observer a new perspective of the celestial object.  You can see also how the nebulosity spans many light years away from the hot O star.

I am glad to report that the efforts to get the telescope to provide the best image possible have paid off.   This image is testament of the capabilities of my observatory.  Stay tuned for more exciting imagery and science.