This looks like a great astronomical project. For those of you who have wondered what the Hubble Telescope has been doing lately. The big advantage of viewing stars in the Andromeda Galaxy vs those in the Milky Way galaxy is that those in the Andromeda galaxy are nearly all the same distance from us, which allows for direct measurements of Absolute Magnitude, something that is impossible when viewing distant stars in the Milky Way.
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What stars compose the Andromeda galaxy? To better understand, a group of researchers studied the nearby spiral by composing the largest image ever taken with the Hubble Space Telescope. The result, called the Panchromatic Hubble Andromeda Treasury (PHAT), involved thousands of observations, hundreds of fields, spanned about a third of the galaxy, and resolved 117 million stars. In the featured composite image, the central part of the galaxy is seen on the far left, while a blue spiral arm is prominent on the right. The brightest stars, scattered over the frame, are actually Milky Way foreground stars. The PHAT data is being analyzed to better understand where and how stars have formed in M31 in contrast to our Milky Way Galaxy, and to identify and characterize Andromeda’s stellar clusters and obscuring dust.
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Observations were done using 6 filters covering from the ultraviolet through the near infrared.

Primary Science Goals

•Star formation histories derived on 50-100 parsec scales
•Improved stellar evolution models, calibrated at UV through NIR wavelengths
•Well-defined catalogs of stellar clusters, at all ages
•Characterization of variations in the stellar mass function from ~3 to 30 solar masses
•Measurements of the mass function and age distributions of stellar clusters
•Maps of extinction from dust, and characterization of the extinction law
•Calibration of star formation indicators
•Age dating of supernova remnants
•Quantitative constraints on the coupling between star formation and the interstellar medium
•Identification and characterization of variable stars
•Kinematic decompositions of structural components
•Cross-identification of multi-wavelength sources and emission line objects
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Instruments used are the Hubble Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS). By using two orbits per pointing, some stars are visible to magnitude 27.9 (that’s a high magnitude). That 2 orbits per pointing adds up to 828 orbits over four years of Hubble observations.
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References:
APOD
Web Home
Slide show of early science results

There is a series of ten scientific papers to come out of this, as well as a dozen or more other scientific papers. In the The Panchromatic Hubble Andromeda Treasury series we have:
I. Bright UV Stars in the Bulge of M31
II. Tracing the Inner M31 Halo with Blue Horizontal Branch Stars
III. Measuring Ages and Masses of Partially Resolved Stellar Clusters
IV. A Probabilistic Approach to Inferring the High Mass Stellar Initial Mass Function and Other Power-law Functions
V. Ages and Masses of the Year 1 Stellar Clusters
VI. The reliability of far-ultraviolet flux as a star formation tracer on sub-kpc scales
VII. The Steep Mid-Ultraviolet to Near-Infrared Extinction Curve in the Central 200 pc of the M31 Bulge
Progression of Large-Scale Star Formation across Space and Time in M31
IX. A Photometric Survey of Planetary Nebulae in M31
X. Ultraviolet to Infrared Photometry of 117 Million Equidistant Stars

All the data is publically available for download from the Barbara A. Mikulski Archive for Space Telescopes, better known as MAST

mollwollfumble said:

There is a series of ten scientific papers to come out of this, as well as a dozen or more other scientific papers. In the The Panchromatic Hubble Andromeda Treasury series we have:
I. Bright UV Stars in the Bulge of M31
II. Tracing the Inner M31 Halo with Blue Horizontal Branch Stars
III. Measuring Ages and Masses of Partially Resolved Stellar Clusters
IV. A Probabilistic Approach to Inferring the High Mass Stellar Initial Mass Function and Other Power-law Functions
V. Ages and Masses of the Year 1 Stellar Clusters
VI. The reliability of far-ultraviolet flux as a star formation tracer on sub-kpc scales
VII. The Steep Mid-Ultraviolet to Near-Infrared Extinction Curve in the Central 200 pc of the M31 Bulge
Progression of Large-Scale Star Formation across Space and Time in M31
IX. A Photometric Survey of Planetary Nebulae in M31
X. Ultraviolet to Infrared Photometry of 117 Million Equidistant Stars

The discussion of PHAT from the original paper half way through the Survey is very readable.
Dalcanton et al. (2012) THE PANCHROMATIC HUBBLE ANDROMEDA TREASURY

Our quest to understand the Universe relies on detailed
knowledge of physical processes that can only be calibrated
nearby. It is impossible to interpret observations
across cosmic time without an underlying understanding
of stellar evolution, star formation, the initial mass
function, the extinction law, and the distance scale, all
of which require detailed studies of individual stars and
the interstellar medium (ISM) on sub-kiloparsec scales.
When the needed studies of stars and gas are carried
out in the Milky Way, they frequently face complications
from line-of-sight reddening, uncertain distances,
and background/foreground confusion. As such, it is
sometimes easier to constrain physical processes in external
galaxies, which are free of the projection effects
that can plague Milky Way studies. Not only are observations
of external galaxies more straightforward to interpret,
but they can also be placed in the larger context
of the surrounding environment (i.e., the ISM, metallicity,
and star formation rate (SFR)). Galaxies in the
Local Group therefore offer an excellent compromise between
being close enough to resolve relatively faint stars,
while being distant enough to unveil the complex processes
that govern star and galaxy evolution in their full
galactic context.

Unfortunately, even the nearest massive galaxies have
sufficiently high stellar surface densities that severe
crowding compromises the detection of fainter, more agesensitive
stellar populations, allowing only the brightest
stars to be studied with typical ground-based angular resolution
in high-surface brightness regions of galaxy disks
(e.g., Massey et al. 2006). However, with the high angular
resolution available from HST, we have the potential
to resolve millions to billions of stars within the Local
Group, grouped into galaxies with a common distance
and foreground extinction. These stars, along with their
ancestors and descendants (e.g., molecular clouds, Hii regions,
variable stars, X-ray binaries, supernova remnants,
etc.), provide transformative tools for strengthening the
foundation on which knowledge of the distant Universe
is based.

Within the Local Group, the Andromeda Galaxy
(M31) offers the best proxy for the properties of more
distant galaxies. It is massive (sampling above the characteristic
stellar mass (3−5×10^10 Msun) over which rapid
systematic changes in galaxies’ stellar populations and
structure occur (e.g., Kauffmann et al. 2003)), hosts spiral
structure, and contains the nearest example of a traditional
spheroidal component (outside the MW). M31 is
also representative of the environments in which typical
stars are found today. More than half of all stars are
currently found in the disk and bulges of disk-dominated
galaxies like M31 (Driver et al. 2007), and more than
3/4 of all stars in the Universe have metallicities within
a factor of two of solar (Gallazzi et al. 2008), comparable
to the typical metallicities of stars in M31.

etc.

From: Witty Rejoinder
ID: 664484
Subject: re: January Chat
NASA shows largest image ever of Andromeda Galaxy
WBIR-TV 3:28 p.m. EST January 20, 2015

NASA released the largest photo ever of the Andromeda Galaxy. The panoramic image taken by the Hubble Space Telescope is 1.5 billion pixels. VPC

NASA released the largest picture ever taken earlier this month, with a staggering 1.5 billion pixels, of the Andromeda Galaxy.

To get an idea of how massive the picture is, you’ll need a 600 HD television screens to look at the whole image.

On Jan. 5, NASA released the image of our closest galactic neighbor.

This YouTube fly-through video shows the detail of the picture captured by NASA’s Hubble Space Telescope. To date, the video has over 2.9 million page views.

The full image takes you through 100 million stars and travels more than 40,000 light-years. Each of those white dots is a sun, much like the sun that powers all life on Earth.

http://www.usatoday.com/story/tech/2015/01/20/nasa-largest-picture-andromeda-galaxy/22052513/