M 52 an open cluster but how far is it?

M 52
3x5 minute exposure, Stromgren y
© Billy Vazquez

M 52 discovered by Messier in 1774 is shown here in an unguided co-added 3x5 minutes Stromgren y filtered exposures.   This image is part of a battery of tests I am excercising on the observatory in preparation for a a new science run that will use Stromgren filters for stellar and luminosity classification.   I am glad to report that the Stromgren y filter which peaks exactly where the Johnson V filter does, is performing well in initial tests.   It is also an opportuinity for you to glimpse at a cluster with a controversial history about its true distance.  Reports vary considerably in the literature and mostly attributed to interstellar extinction.

Maia a Star in the Pleiades Cluster

Maia in Pleiades
5 min unguided exposure
© Billy Vazquez

The Pleiades Cluster also known as the Seven Sisters will always make one of the favorite astronomers stops.   Why you say? Well is bright, can be seen with the naked eye and it harbors these beautiful Blue B stars.   More importantly, there is interstellar dust that reflects the light of this enormous stars, making it look nebula like.   Well not everything is forever and astronomers have determined that in about 250 million years this cluster will be stripped away of its stars by gravitational forces.   The image I show you today is one of the many tests I am performing on my renovated observatory.  Maia one of the Pleiades stars is smacked in the middle ( more or less a bit southeast ). A 5 minute raw unguided exposure, on a full moon night, which is why you can barely see any nebulosity. Still a very nice image, with full width half maximum of 2.1 arc seconds.

M13 - Hercules Globular Cluster

M13 Hercules Globular Cluster
VAO, Webster NY
FWHM 2.2", 1x1 bin, 0.54 "/pix
12" Meade SCT
© Billy Vazquez

M13, the Hercules Globular Cluster was discovered by Edmund Halley in 1714 and catalogued by Charles Messier on 1764.   This cluster at an apparent magnitude of 6 contains about a million stars on an approximate sphere spanning 150 light years.  The image is a composite of  5x1 minute exposures unguided at f/6 on the VAO's 12" Meade to test the new Paramount MX mount.  Close inspection of the stars show a small drift of about 2 arc seconds per minute.  This is likely due to a non accurate PEC correction.  Still nothing to be sniffed at a plate scale of 0.54"/pixel.  The seeing was transparent and steady on July 29th, 2012 the reported FWHM was 2.2"

Opposition of Eros

Eros is an asteroid in a high elliptical orbit around the Sun.  It was discovered in 1878 and it is 33 km wide.  

Back in the late 1920's, astronomers around the world knew that Eros will be again close to the Earth in 1931.  They made calculations of the star field where Eros will transit to attempt to calculate the distance to Eros. This was a large undertaking as precise measurements of the stars needed to be done as well as of Eros.  

Simultaneous observations of Eros from different parts of the world provides the necessary data to calculate distances using parallax. 

Three weeks ago, Eros was in opposition again at a distance of 0.2 AU from Earth. Astronomers around the world are attempting a re-enactment of the observations and calculations done back in 1931.   Not only will we be able to determine the distance to Eros, but we could estimate with these measurements the size of our Solar system. The animated image was captured from VAO in Webster, NY and shows (roughly), Eros transiting at a speed on the plane of the sky of 7 arc seconds per minute. 

Photometry for Astronomers

Photometric results of VAO Observations on 11/21/2011

Astronomers interested in the variability of stars need a tool to understand how they vary in time.   This tool is called photometry and it is widely used by astronomers to study not only intrinsic star variability but the more familiar exoplanet transit searches.    It is also used to study galaxies and other extended objects.  So why study changes in "brightness"?

Changes in brightness can lead to the discovery of eclipsing binaries, transiting exoplanets, exotrojans and exomoons.   It can tell you about the morphology of Active Galactic Nuclei and about the properties of supernovae explosions.  You can infer from the data when you collect it over time about the physical properties of the object you are studying.

The plots to the right are examples of light curves or in other words many measurements of the intensity of stars over a period of time.  On the horizontal axis you have number of exposures. On this particular case each tick on the axis is roughly 80 seconds.  On the vertical we have the instrumental magnitude of the star.   As you can tell by the graphs there are stars on this ensemble that vary on time scales of hours.  These measurements were taken on VAO in Webster NY and the graphs are the results of the photometric pipeline I setup for this particular field.

The WIYN 0.9m Observatory @ Kitt Peak

Kitt Peak National Observatory

Today there are no pretty pictures of the wonders of the Universe from the VAO observatory in Webster, NY. Instead, I bring you images of where I will be for the next week,  Kitt Peak National Observatory.  Located 56 miles from Tucson, Arizona at an elevation of 6,875 feet above sea level.   KPNO has the largest collection of telescopes in the world. 24 optical telescopes and 2 radio observatories.  

So why KPNO?

On the left, the WIYN 0.9 m Observatory

KPNO houses the WIYN consortium 0.9 meter telescope of which Rochester Institute of Technology is a partner among other educational institutions.   As part of the partnership, faculty and students of RIT  have the opportunity to conduct research and educational projects.   

Why is this important to me, you say? Well to begin, the night sky at KPNO is one of the best in the nation and the opportunity to image with a telescope that is 3 times the aperture size of the one I have is compelling.  Not to mention this will advance 2 of the projects I am currently working on.  The first project is on AGN (Active Galactic Nuclei), galaxies where their central super massive blackhole is accreating mass.  The second project is on the characterization of transiting exoplanets and their apsidal precession due to the effects predicted by Albert Einstein's theory of General Relativity.

Stay tuned for the results of this trip!

M78, McNeil's Nebula, v1647Ori what do these things have in common?

M78, McNeil's Nebula and v1647Ori
©Billy Vazquez, 2011 @ VAO Webster, NY

They are all part of the Orion Molecular Cloud Complex.  They are also part of these image taken from VAO a few nights ago.  M78 on the upper left corner of these image is an HII region and it the brightest and most prominent object of this field but regardless there are several other nebula like objects, for example McNeil's Nebula.   

McNeil's Nebula has a very interesting story behind it.   Discovered by McNeil in 2003 after having done an exhaustive search on this field at different epochs.  But was it really a new object in the sky?  Apparently as close to the mid 1960s and by no other than an amateur astronomer(Evered Kramer).  There is clear evidence that the nebula was visible then.   So how come it disappeared just to reappear again for McNeil to find?  This is still the topic of active research.   The prevalent explanation is that the young star v1647Ori has episodic outburst whose light reflects and scatters by the dust in McNeil's Nebula.

These outbursts from young stars and their associated nebulosity are coined Herbig-Haro objects and they are like I said still the subject of astronomical research, so that we can understand the physics that powers this phenomena.