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#62. astrodeep200407 a g HUDF heic0611aa
Click on All Sizes button and select Original to see highest resolution image.
In the full HUDF view, saturating the colors reveals huge regions with very different overall colors -- this deserves research.
www.spacetelescope.org/images/html/zoomable/heic0611a.html Zoomable
The boxes are 3 arcsec wide, 100x100 pixels, with 0.03 arc-second per pixel. They are in order of apparent brightness, from 1 to 28.
The half-light galaxy diameters are about 1.6 kpc = 5220 Ly, as 1 kpc = 1000 parsecs = 3262 Ly. Our Milky Way galaxy is about 100,000 Ly wide.
notable bright blue tiny sources on darker 3D fractal web in HUDF VLT ESO 28 images from 506 galaxies, z about 6 , RJ Bouwens, GD Illingworth, JP Blakeslee, M Franx 2008.02.04 draft 36 page: Rich Murray 2008.08.17
rmforall.blogspot.com/2008_08_01_archive.htm
Sunday, August 17, 2008
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www.flickr.com/photos/rmforall/1363979470/in/photostream/
Double click on photo and click on All Sizes button and select Original to see highest resolution image, as well as some smaller images.
www.spacetelescope.org/images/html/zoomable/heic0611a.html Zoomable
The boxes are 3 arcsec wide, 100x100 pixels, with 0.03 arc-second per pixel. They are in order of apparent brightness, from 1 to 28.
The HUDF is made of 0.03 arc-second pixels, 6200X6200, 186X186 arc-seconds, 3.1X3.1 arc-minutes, about a tenth of the width of the Moon or Sun, 0.5X0.5 degrees.
'In this image, blue and green correspond to colors that can be seen by the human eye, such as hot, young, blue stars and the glow of Sun-like stars in the disks of galaxies.
Red represents near-infrared light, which is invisible to the human eye, such as the red glow of dust-enshrouded galaxies.'
Four wavelength filters collected the B435, V606, i775, z850 wavelength images for the observed blue, violet, near infrared, infrared images -- combined in this vast image with tiny 0.03 arc-second pixels.
'Galaxy sizes: Typical i-dropouts at z850,AB about 27 (from the HUDF-Ps and HUDF) have PSF-corrected half-light radii of about 0.8 kpc [2610 Ly] or about 0.14 arc-second (Figure 6: §3.7). [ So diameter is 1.6 kpc = 5220 Ly, as 1 kpc = 1000 parsecs = 3262 Ly. Our Milky Way galaxy is about 100,000 Ly wide. ]'
'The reheating, driven by the galaxies ultraviolet starlight, transformed the gas between galaxies from a cold, dark hydrogen soup to a hot, transparent plasma over only a few hundred million years.
With Hubble's help, astronomers are now beginning to see the kinds of galaxies that brought about the reheating.'
'The first 900 million years (Myr) to redshift z about 6 (the first seven per cent of the age of the Universe) remains largely unexplored for the formation of galaxies.'
'It is not at all clear how galaxies built up from the first stars when the Universe was about 300Myr old (z about 12-15) to z about 6, just 600Myr later.'
'The nearest galaxies -- the larger, brighter, well-defined spirals and ellipticals -- thrived about 1 billion years ago, when the cosmos was 13 billion years old.'
'The image required 800 exposures taken over the course of 400 Hubble orbits around Earth. The total amount of exposure time was 11.3 days, taken between Sept. 24, 2003 and Jan. 16, 2004.'
www.spacetelescope.org/images/html/heic0611a.html
Probing the distant Universe for young galaxies
This Hubble Space Telescope image shows 28 of the brightest of 506 young galaxies that existed when the universe was less than 1 billion years old.
The galaxies were uncovered in a study of two of the most distant surveys of the cosmos, the Hubble Ultra Deep Field (HUDF), completed in 2004, and the Great Observatories Origins Deep Survey (GOODS), made in 2003.
Just a few years ago, astronomers had not spotted any galaxies that existed significantly less than 1 billion years after the Big Bang.
The galaxies spied in the HUDF and GOODS surveys are blue galaxies brimming with star birth.
The large image at left shows the Hubble Ultra Deep Field, taken by the Hubble telescope.
The numbers next to the small blue boxes correspond to close-up views of 28 of the newly found galaxies at right. [ arranged by apparent brightness from 1 to 28 ]
The galaxies in the postage-stamp size images appear red because of their tremendous distance from Earth. The blue light from their young stars took nearly 13 billion years to arrive at Earth. During the journey, the blue light was shifted to red light due to the expansion of space.
Credit: NASA, ESA, R. Bouwens and G. Illingworth (University of California, Santa Cruz, USA)
www.spacetelescope.org/news/html/heic0611.html
News Release -- heic0611: Hubble finds hundreds of young galaxies in the early Universe
21-Sep-2006: Astronomers analyzing two of the deepest views of the cosmos made with the NASA/ESA Hubble Space Telescope have uncovered a gold mine of galaxies, more than 500 that existed less than a billion years after the Big Bang.
These galaxies thrived when the cosmos was less than 7 percent of its present age of 13.7 billion years.
This sample represents the most comprehensive compilation of galaxies in the early Universe, researchers said.
The discovery is scientifically invaluable for understanding the origin of galaxies, considering that just a decade ago early galaxy formation was largely uncharted territory.
Astronomers had not seen even one galaxy that existed when the Universe was a billion years old, so finding 500 in a Hubble survey is a significant leap forward for cosmologists.
The galaxies unveiled by Hubble are smaller than today's giant galaxies and very bluish in colour, indicating they are ablaze with star birth.
The images appear red because of the galaxies' tremendous distance from Earth.
The blue light from their young stars took nearly 13 billion years to arrive at Earth.
During the journey, the blue light was shifted to red light due to the expansion of space.
'Finding so many of these dwarf galaxies, but so few bright ones, is evidence for galaxies building up from small pieces -- merging together as predicted by the hierarchical theory of galaxy formation,' said astronomer Rychard Bouwens of the University of California, Santa Cruz, USA who led the Hubble study.
Bouwens and his team spied these galaxies in an analysis of the Hubble Ultra Deep Field (HUDF), completed in 2004, and the Great Observatories Origins Deep Survey (GOODS), made in 2003.
The results were presented on August 17 at the 2006 General Assembly of the International Astronomical Union, and will be published in the November 20 issue of the Astrophysical Journal.
The findings also show that these dwarf galaxies were producing stars at a furious rate, about ten times faster than is happening now in nearby galaxies.
Astronomers have long debated whether the hottest stars in early star-forming galaxies, such as those in this study, may have provided enough radiation to reheat the cold hydrogen gas that existed between galaxies in the early Universe.
The gas had been cooling since the Big Bang.
'Seeing all of these starburst galaxies provides evidence that there were enough galaxies 1 billion years after the Big Bang to finish reheating the Universe,' explained team member Garth Illingworth of the University of California, Santa Cruz. 'It highlights a period of fundamental change in the Universe, and we are seeing the galaxy population that brought about that change.'
In terms of human lifetimes, cosmic events happen very slowly.
The evolution of galaxies and stars, for example, occurs over billions of years.
Astronomers, therefore, rarely witness dramatic, relatively brief transitions that changed the Universe.
One such event was the Universe is 'reheating'.
The reheating, driven by the galaxies ultraviolet starlight, transformed the gas between galaxies from a cold, dark hydrogen soup to a hot, transparent plasma over only a few hundred million years.
With Hubble's help, astronomers are now beginning to see the kinds of galaxies that brought about the reheating.
Just a few years ago, astronomers did not have the technology to hunt for faraway galaxies in large numbers.
The installation of the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope in 2002 allowed astronomers to probe some of the deepest recesses of our Universe.
Astronomers used the ACS to observe distant galaxies in the HUDF and GOODS public surveys.
Another major step in the exploration of the Universe's earliest years will occur if Hubble undergoes its next upgrade with the Wide Field Planetary Camera 3 (WFC3).
The WFC3's infrared sensitivity will allow it to detect galaxies that are so far away their starlight has been stretched to infrared wavelengths by the expanding Universe.
The galaxies uncovered so far promise that many more galaxies at even greater distances are awaiting discovery by the NASA/ESA/CSA James Webb Space Telescope (JWST), scheduled to launch in 2013.
Co-author Marijn Franx, member of the ESA JWST NIRSPEC science team, explains: 'The JWST will be able to see even further back into the early Universe, and glimpse the first objects that formed.
ESA's NIRSPEC instrument, can even measure the exact distances of these objects.'
Notes for editors:
The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
The members of the science team are Rychard Bouwens and Garth Illingworth (University of California, Santa Cruz),
John Blakeslee (Washington State University),
and Marijn Franx (Leiden University).
NASA, ESA, R. Bouwens and G. Illingworth (University of California, Santa Cruz, USA)
NASA's press release
Contacts:
Marijn Franx
Leiden Observatory, Leiden, the Netherlands
Tel: +31-71-5275870
E-mail: franx@strw.leidenuniv;
Rychard Bouwens
University of California, Santa Cruz, California, USA
Tel: +1-831-459-5276
E-mail: bouwens@ucolick.org;
Garth Illingworth
University of California, Santa Cruz, California, USA
Tel: +1-831-459-2843
E-mail: gdi@ucolick.org;
John Blakeslee
Washington State University, Pullman, Washington, USA
Tel: +1-509-335-2414
E-mail: jblakes@wsu.edu;
Lars Lindberg Christensen
Hubble/ESA, Garching, Germany
Tel: +49-89-3200-6306
Cellular: +49-173-3872-621
E-mail: lars@eso.org;
Donna Weaver
Space Telescope Science Institute, Baltimore, Md., USA
Tel: +1-410-338-4493
E-mail: dweaver@stsci.edu;
Copyright-free material (more info).
hubblesite.org/newscenter/archive/releases/2004/07/image/a/
Hubble Ultra Deep Field Image Reveals Galaxies GaloreSTScI-PRC2004-07a
Galaxies, galaxies everywhere -- as far as NASA's Hubble Space Telescope can see. This view of nearly 10,000 galaxies is the deepest visible-light image of the cosmos. Called the Hubble Ultra Deep Field, this galaxy-studded view represents a 'deep' core sample of the universe, cutting across billions of light-years.
The snapshot includes galaxies of various ages, sizes, shapes, and colors.
The smallest, reddest galaxies, about 100, may be among the most distant known, existing when the universe was just 800 million years old.
The nearest galaxies -- the larger, brighter, well-defined spirals and ellipticals -- thrived about 1 billion years ago, when the cosmos was 13 billion years old.
In vibrant contrast to the rich harvest of classic spiral and elliptical galaxies, there is a zoo of oddball galaxies littering the field.
Some look like toothpicks; others like links on a bracelet.
A few appear to be interacting.
These oddball galaxies chronicle a period when the universe was younger and more chaotic.
Order and structure were just beginning to emerge.
The Ultra Deep Field observations, taken by the Advanced Camera for Surveys, represent a narrow, deep view of the cosmos.
Peering into the Ultra Deep Field is like looking through an eight-foot-long soda straw.
In ground-based photographs, the patch of sky in which the galaxies reside (just one-tenth the diameter of the full Moon) is largely empty.
Located in the constellation Fornax, the region is so empty that only a handful of stars within the Milky Way galaxy can be seen in the image.
In this image, blue and green correspond to colors that can be seen by the human eye, such as hot, young, blue stars and the glow of Sun-like stars in the disks of galaxies.
Red represents near-infrared light, which is invisible to the human eye, such as the red glow of dust-enshrouded galaxies.
The image required 800 exposures taken over the course of 400 Hubble orbits around Earth. The total amount of exposure time was 11.3 days, taken between Sept. 24, 2003 and Jan. 16, 2004.
Object Names: Hubble Ultra Deep Field, HUDF
Image Type: Astronomical
Credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team
dipastro.pd.astro.it/venice06/oral/Bouwens_Venice06.ppt
RJB, GDI give 40 slide Power Point Import presentation in Venice 2006.03.31
arxiv.org/PS_cache/astro-ph/pdf/0509/0509641v6.pdf 36 page
Draft version February 4, 2008
Preprint typeset using LATEX style emulateapj v. 04/21/05
Galaxies at z about 6: the UV luminosity function and luminosity density from 506 HUDF, HUDF-PS, and GOODS i-dropouts
Rychard J. Bouwens 3, bouwens@ucolick.org;
Garth D. Illingworth 3, www.ucolick.org/~gdi/ gillingw@ucsc.edu;
John P. Blakeslee 4, jblakes@wsu.edu;
Marijn Franx 5 franx@strw.leidenuniv.nl;
1 Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for
Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs #9803.
2 Observations have been carried out using the Very Large Telescope at the European Southern Observatory (ESO) Paranal
Observatory under program ID: LP168.A-0485.
3 Astronomy Department, University of California, Santa Cruz, CA 95064
4 Department of Physics & Astronomy, Washington State University, Pullman, WA 99164-2814 and
5 Leiden Observatory, Postbus 9513, 2300 RA Leiden, Netherlands.
Draft version February 4, 2008
ABSTRACT [ z = redshift due to increasing distance and time from us here and now, where z = 0 ]
We have detected 506 i-dropouts (z about 6 -- galaxies) in deep, wide-area HST ACS fields: HUDF, enhanced GOODS, and HUDF-Parallel ACS fields (HUDF-Ps).
The contamination levels are under 8% (i.e., over 92% are at z about 6).
With these samples, we present the most comprehensive, quantitative analyses of z about 6 -- galaxies yet and provide optimal measures of the UV luminosity function (LF) and luminosity density at z about 6, and their evolution to z about 3.
We redetermine the size and color evolution from z about 6 to z about 3.
Field-to-field variations (cosmic variance), completeness, flux, and contamination corrections are modeled systematically and quantitatively.
After corrections, we derive a rest-frame continuum UV (about 1350 A) LF at z about 6 that extends to M1350,AB about −17.5 (0.04L*, z=3).
There is strong evidence for evolution of the LF between z about 6 and z about 3, most likely through a brightening (0.6+-0.2 mag) of M* (at 99.7% confidence) though the degree depends upon the faint-end slope.
As expected from hierarchical models, the most luminous galaxies are deficient at z about 6.
Density evolution (phi*) is ruled out at over 99.99% confidence.
Despite large changes in the LF, the luminosity density at z about 6 is similar (0.82 ± 0.21x) to that at z about 3.
Changes in the mean UV color of galaxies from z about 6 to z about 3 suggest an evolution in dust content, indicating the true evolution is substantially larger: at z about 6 the star formation rate density is just about 30% of the z about 3 value.
Our UV luminosity function is consistent with z about 6 galaxies providing the necessary UV flux to reionize the universe.
Subject headings: galaxies: evolution -- galaxies: high-redshift
2.1. ACS HUDF
The B435V606i775z850 [colors blue, violet, near infrared, infrared] images used for this analysis are the v1.0 reductions of the HUDF (Beckwith et al. 2006), binned on a 0.03′′ pixel scale.
3.2. i-dropouts in the HUDF
Applying the above selection criteria to the HUDF results in a sample of 122 i-dropouts.
Objects range in magnitude from z850,AB = 25.0 to 29.4 (the 8 d limit).
At z about 6, this corresponds to 0.04 - 2.2 times the characteristic rest-frame UV luminosity at z about 3 (Steidel et al. 1999).... V606i775z850 color cutouts are provided in Figure 1 for the brightest 28 i-dropouts from the HUDF.
Fig. 1. -- Postage stamps (V606i775z850 color images) of the brightest 28 i775-dropouts from the HUDF [ from the 122 galaxies found ].
Objects are ordered in terms of their z850-band magnitude. [infrared]
The z850-band magnitudes and object IDs are shown above and below each object, respectively.
Each postage stamp is 3.0′′ in size.
These high S/N images show definitive evidence for assymetries, mergers, and other interactions -- similar to that seen at lower redshifts (z about 2 - 5).
Galaxy sizes: Typical i-dropouts at z850,AB about 27 (from the HUDF-Ps and HUDF) have PSF-corrected half-light radii of about 0.8 kpc [2610 Ly] or about 0.14 arc-second (Figure 6: §3.7). [ So diameter is 1.6 kpc = 5220 Ly, as 1 kpc = 1000 parsecs = 3262 Ly. Our Milky Way galaxy is about 100,000 Ly wide. ]
www.ucolick.org/~gdi/docs/nature_05156.pdf 15 page
LETTERS
Vol 443, 14 September 2006 doi:10.1038/nature05156
Rapid evolution of the most luminous galaxies during the first 900 million years
Rychard J. Bouwens, Garth D. Illingworth
The first 900 million years (Myr) to redshift z about 6 (the first seven per cent of the age of the Universe) remains largely unexplored for the formation of galaxies.
Large samples of galaxies have been found at z about 6 (refs 1-4) but detections at earlier times are uncertain and unreliable.
It is not at all clear how galaxies built up from the first stars when the Universe was about 300Myr old (z about 12-15) to z about 6, just 600Myr later.
Here we report the results of a search for galaxies at z about 7-8, about 700Myr after the Big Bang, using the deepest near-infrared and optical images ever taken.
Under conservative selection criteria we find only one candidate galaxy at z about 7-8, where ten would be expected if there were no evolution in the galaxy population between z about 7-8 and z about 6.
Using less conservative criteria, there are four candidates, where 17 would be expected with no evolution.
This demonstrates that very luminous galaxies are quite rare 700Myr after the Big Bang.
The simplest explanation is that the Universe is just too young to have built up many luminous galaxies at z about 7-8 by the hierarchical merging of small galaxies.
____________________________________________________________
See similar images:
ubiquitous bright blue 1-12 pixel sources on darker 3D fractal web in five 2007.09.06 IR and visible light HUDF images, Nor Pirzkal, Sangeeta Malhotra, James E Rhoads, Chun Xu, -- might be clusters of earliest hypernovae in recent cosmological simulations: Rich Murray 2008.08.17
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Sunday, August 17, 2008
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bright blue 1-4 pixel sources on darker 3D fractal web in IR and visible light HUDF images -- might be the clusters of earliest hypernovae in the Naoki Yoshida and Lars Hernquist simulation: Rich Murray 2008.07.31
rmforall.blogspot.com/2008_07_01_archive.htm
Thursday, July 31, 2008
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Rich Murray, MA Room For All rmforall@comcast.net
505-501-2298 1943 Otowi Road Santa Fe, New Mexico 87505
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Just uploading a grayscale version of this so I can keep all the observations from this proposition organized better. The color version is here: flic.kr/p/24eVAda
Establishing HST's Low Redshift Archive of Interacting Systems
All Channels: ACS/WFC F606W
North is 20.29° clockwise from up.
This Picture of the Week shows a huge cloud of gas around the distant quasar SDSS J102009.99+104002.7, taken by the Multi Unit Spectroscopic Explorer (MUSE) instrument on ESO’s Very Large Telescope (VLT) at the Paranal Observatory. Quasars are the luminous centres of active galaxies, which are kept active by material falling onto the central supermassive black hole. This quasar and its surrounding cloud are at a redshift larger than 3, meaning that they are seen as they were only about 2 billion years after the Big Bang.
More information: www.eso.org/public/images/potw1747a/
Credit:
ESO/Arrigoni Battaia et al.
NGC 5457 (M101 = PGC 50063 = Arp 26), The Pinwheel Galaxy
Discovered (Mar 27, 1781) by Pierre Méchain
Recorded (without observational verification) by Charles Messier as M101
Also observed (later in 1781) by Charles Messier
Also observed (May 4, 1831) by John Herschel
A magnitude 7.9 spiral galaxy (type SAB(rs)cd?) in Ursa Major (RA 14 03 12.4, Dec +54 20 58)
Historical Identification: Per Dreyer, NGC 5457 (= GC 3770 = JH 1744, M101, 1860 RA 13 58 14, NPD 34 58.6) is "pretty bright, very large, irregularly round, very suddenly much brighter middle with bright small nucleus". The position precesses to RA 14 03 11.5, Dec +54 20 58, essentially dead center on the galaxy listed above and the description fits, so the identification is certain.
Discovery Information: Usually Messier verified discoveries reported to him by Méchain, and listed both his friend's prior discovery and his own observation. However, at the time of Méchain's observation of what became M101, the deadline for additions to the 1784 publication of Messier's last Catalog was fast approaching, so he did not verify the observation until later. Messier's description of the object was only recorded (without the date of his observation) in a handwritten note in his personal copy of the printed version. (A similar situation applies to M102 and M103, the last objects recorded by Messier.)
Physical Information: Listed in Halton Arp's Atlas of Peculiar Galaxies as Arp 26, an example of a spiral galaxy with one heavy arm. M101's recessional velocity of only 240 km/sec is too small in comparison to peculiar (non-Hubble-expansion) velocities to provide a reliable estimate of its distance. Redshift-independent distance estimates range from 18 to 29 million light years. Given that and its apparent size of 28 by 26 arcmin (nearly the same size as the full moon), M101 is nearly 200 thousand light years across.
"Excerpt courtesy of Courtney Seligman"
cseligman.com/text/atlas/ngc54a.htm#5457
Image... Cherryvalley Observatory (I83). Telescope: 0.2-m SCT & SBIG STL-1301E CCD Camera @f7.6. Image Scale 2.17 arcsec/pixel, Field of View 46 x 37 arcmins.
Flat field and dark subtract calibration frames. Combined Stack of three images of 120 seconds each unfiltered and unbinned. CCD operating temperature: -35 degrees. Image acquisition and processing: CCD Soft v5, TheSky6 Professional and Mira Pro v7. February 18th 2016.
Dr. Halton Arp originally compiled the Atlas of peculiar galaxies with photographs he made mainly using the Palomar 200-inch telescope and the 48-inch Schmidt telescope between the years 1961 to 1966. Original image can be found here: ned.ipac.caltech.edu/level5/Arp/Figures/big_arp26.jpeg
NGC4216, NGC4206, NGC4222 Galaxy Group, The Virgo Triplet
NGC4216 is a large spiral galaxy in the constellation of Virgo, morphological class SAB(s)b, intermediate between barred and unarred spirals. The Carnegie Atlas of Galaxies (1994) regards it as prototypical because it appears in many textbooks to illustrate the nucleus, bulge, disk, dust lanes, and spiral structure of major spiral galaxies. More recently it has been the subject of several studies related to galaxy mergers, stellar streams, and multi-band analysis of its gas and dust content. Along with its two large companions, NGC4206 and NGC4222, the galaxy is a peripheral member of the Virgo Galaxy Cluster. All three are rapidly moving toward us around the cluster's center of gravity. High "peculiar velocities" through space render their redshifts unsuitable for distance calculations. See Section 5, Fig. 6.
www.cloudynights.com/articles/cat/articles/basic-extragal...
In the chart on the annotated image, their derived properties (except for the redshift radial velocity) are calculated from the mean of the redshift independent distance measurements, and are enclosed in parentheses. Integrated apparent magnitudes and derived absolute magnitudes for all three galaxies are understated due to their edge-on orientation which presents a smaller luminous area to the observer, and also due to light absorption and scatter by gas and dust in the galactic plane. The three galaxies are gravitationally bound to each other and to the Virgo Cluster, but do not show evidence of significant tidal disruption.
NGC4216 has a small, very bright active galactic nucleus of the Hii LINER type which hosts an actively accreting supermassive black hole. Silchenko et al. (1999) report that high resolution spectroscopy reveals a distinct high metallicity nucleus and a circumnuclear ring of starburst activity, resulting in a star population much younger than the surrounding bulge. In most spiral galaxies the nuclear region and the bulge are composed of ancient, very low metallicity stars. It is thought that NGC4216 has a small bar which triggers new star formation by attracting and disrupting interstellar gas and dust clouds. Although some sources describe NGC4216 as a low hydrogen content "anemic galaxy", optical images clearly show numerous bright blue floccules of starburst activity in the disk. In their VLA (Very Large Array radio telescope) study of Virgo spirals, Chung et al. (2010) report moderate atomic hydrogen (Hi) flux and mass within the disk, but low Hi density on the surface. It appears the galaxy has undergone surface stripping by thermal evaporation, gravitational interaction, or "ram stripping". At inclination angle of 85*, the galaxy's disk is ideally oriented to present prominent dust lanes and pillar-like "plumes" of stars arising above the galactic plane, which appear as low-lying blue clouds on the attached photograph. The origin of the plumes is not well understood, but is presumed to be caused by interactions with the intergalactic medium within the Virgo Cluster.
NGC4216 is surrounded by a large, diffuse stellar halo containing 2-4 stellar streams (not visible on my image) and a complex system of around 700 globular clusters, nearly 5 times as many as the Milky Way. The stellar streams appear to be gravitationally deformed remnants of at least two satellite dwarf galaxies in the process of accretion. Compared to other galaxies in the Virgo Cluster, NGC 4216 appears to be undergoing a high rate of galaxy mass assembly.
iopscience.iop.org/article/10.1088/0004-637X/767/2/133/pdf
On the annotated image, several faint, diffuse objects which I suspect to be dwarf candidates are marked as DC. The large number of globular clusters were probably brought in by dwarf galaxies during numerous mergers.
The field includes a number of remote faint objects described in the chart on the annotated image. Among these are three very luminous quasars which are presently receding at superluminal velocities, and lie beyond the cosmic event horizon. Two of the quasars (marked with +) appear to be significantly brighter than their listed apparent magnitudes. Since quasar luminosity depends on the rate of accretion, which can change depending on the availability of matter, quasars commonly manifest variability of up to several magnitudes over a period of days to years. See Section 25 here
www.cloudynights.com/articles/cat/articles/basic-extragal...
The most distant object is [VV2006] J121506.9+130559, lying at a light travel distance (lookback time) of 12 billion ly. In the present cosmological epoch, its proper (comoving) distance is approximately 23.3 Bly.
Image details:
-Remote Takahashi TOA 150 x 1105 mm, Paramount GT GEM
-OSC 20 x 300 sec + 25 x 300 sec taken in 2021, 2x drizzle, 50% linear crop
-Software: DSS, XnView, Starnet++ 2, StarTools 1.3 and 1.7, Cosmological Calculator 3
Compared to the last year's image, there is a mild gain in resolution, and >0.5 mag gain in the limiting magnitude.
The Redshift Star Fighter uses a gravity accumulator to both mask its location and move at sublight speeds.
NGC 7479, Caldwell 44, Pegasus, Propeller Galaxy
NGC7479 is a distorted barred spiral galaxy in the constellation of Pegasus, discovered by W. Herschel in 1784. With apparent diameter of 4.4 arcmin, and apparent magnitude of 10.85 (V), visual observation calls for large apertures. However, its basic structures are evident photographically with modest telescopes. From its measurable properties we can derive light travel distance (lookback time) of 110 million light years, redshift recession velocity of 2,379 km/s, actual diameter of 140,000 ly, and absolute magnitude of -21.83 (V), approximately 1.5 times as bright as the Milky Way. NGC7479 has an active galactic nucleus (AGN) which is 8.5 times brighter in the near IR (z filter) than in the visible band, and which emits narrow spectral lines of weakly ionized elements. These characteristics classify it as a Seyfert 2 and a LINER galaxy. It is powered by an actively accreting central supermassive black hole (SMBH) obscured by a large, dense cloud of light-absobing gas and dust. The nucleus is also active at radio frequencies, suggesting the SMBH has polar jets emitting synchrotron radiation. Bright blue floccules in the spiral arms and even within the bar are OB Associations, or vast clusters of recently formed blue giant stars which emit most of their energy in the ultraviolet band. NGC7479 is an isolated field galaxy with no nearby neighbors. Starburst activity, several stellar streams, and gravitational distortion in the W spiral arm are thought to have been caused by a merger with one or more dwarf satellite galaxies between 300 and 100 million years ago.
As the annotated image illustrates, different spectral bands reveal different details within a galaxy. In the ultraviolet band (GALEX), the most prominent features are OB associations, starburst regions, and reflection nebulae. The compact, round UV signal overlapping the N arm of the bar may be the remnant nucleus of a merged dwarf galaxy. The NGC7479 nucleus is not prominent because it is surrounded by a thick layer of gas and dust which absorb and scatter predominantly UV light. However, the brightest feature on the infrared (2MASS) image of the galaxy is precisely the main galactic nucleus with a central SMBH, because longer wavelengths are less obsured. The bulge and the bar are also distinctive due to the presence of ancient cool and red Population II stars. Radio frequency imaging of the galaxy reveals the presence of a bright jet-like feature, centered on the nucleus, and extending through the bar about 20,000 light years in the N and in the S direction. The jet's spiral morphology mildly curves in the direction opposite to that of the stellar and gaseous spiral arms, suggesting that the two structures may be counter-rotating. Jet bending can be caused by precession of the central SMBH accretion disk, by the presence of a binary central SMBH, and/or an off center merger with another galaxy. Based on the rate of expansion and the maximum distance from the nucleus, the jet is felt to be less than 10 million years old.
A large galaxy cluster is visible in the remote background at an estimated light travel distance of 1.5 to 2 billion light years. Only two of these have assigned identifiers. Their measurable and derived properties are listed in the chart on the annotated image.
Image details:
-Remote Takahashi TOA 150 x 1105 mm, Paramount GT GEM,
-OSC 34 x 300 sec, 2x drizzle, 50% linear crop,
-Software: DSS, XnView, StarNet++ v2, StarTools v1.3 and 1.7, Cosmological Calculator v3
Horsehead and Flame nebulae located east of Orion's Belt - part of the Orion Molecular Cloud complex. Seven 180-sec exposures in R-G-B (plus dark) with SBIG STT8300M CCD camera - unguided using a WO 132mm f/7 refractor on an AP1200GTO mount. Taken early hours of Dec 1, 2012 from Redshift Observatory in New Mexico.
Interacting Galaxies NGC 5395 and NGC 5394 (ARP 84), and 2 Remote Quasars, Canes Venatici
NGC 5395 and NGC 5394 are gravitationally interacting spiral galaxies in the constellation of Canes Venatici, collectively known as the Heron Galaxy.They are also listed as ARP 84 in the Atlas of Peculiar Galaxies which includes examples of unusual structures found among galaxies. The pair was first documented by W. Herschel in 1787, the same year he discovered two moons of Uranus. As the chart below indicates, the larger member, NGC 5395, is about 3.5 arcmin in angular size, and 11.68 in apparent magnitude (V). Its redshift-based recession velocity is 3,451 km/s, and light travel distance about 160 Mly. From this we can calculate its actual size to be around 160,000 ly - a giant galaxy, 25% larger than the Milky Way, and about 2.5 times brighter. Its morphological classification is SA(s)b pec - a peculiar unbarred spiral. Its NW quadrant appears deformed by gravitational interaction with NGC 5394, which either grazed or passed right through its spiral arms millions of years ago. The interface between the two galaxies has a distinct blue color revealing that the turbulence in the intragalactic medium caused by tidal forces precipitated rapid formation of numerous giant, hot, blue stars. The two galaxies are gravitationally bound, in the early stages of merging, and will eventually form a large lenticular galaxy. NGC 5395 has an active galactic nucleus of the Seyfert II type, indicating the presence of an actively accreting central supermassive black hole. Although the nucleus does not appear especially bright in the visible band, in the infrared it is as bright as the rest of the galaxy.
NGC 5394, the smaller member of the pair, is engaged in a slow cosmic dance with NGC 5395, where a single turn lasts hundreds of millions of years. Measurable properties suggest the galaxy is about 30% smaller than the Milky Way, but also 30% brighter, probably due to starburst activity caused by tidal interactions. Lying at a distance of 159 Mly, it is separated from its partner by only 1 Mly, offering a spectacular view of the night sky to any life forms intelligent enough to appreciate it. This galaxy is classified as a peculiar barred spiral, and also as a Luminous Infrared Galaxy, or a LIRG, which emits more energy in the IR band than all other bands combined. In the optical band, virtually all LIRGs are found to be interacting or merging galaxies with central supermassive black holes (SMBH). Their high intrinsic luminosity is due to active galactic nuclei (AGN) and also to very high rates of new star formation, between 100 and 3,000 times the rate observed in quiescent spiral galaxies. LIRGs are less prominent in the visible band because their active nuclei are surrounded by dense clouds of gas and dust which absorb intense ultraviolet radiation from the central SMBH, and re-emit the energy in the form of heat in the infrared band.
www.cloudynights.com/articles/cat/articles/basic-extragal...
The field is strewn with numerous distant galaxies, most of which carry no identifier. Properties of the more prominent ones are listed in the chart below. Of these are notable 2MASX J13582258+3734549, which shows what the Milky Way would look like at a distance of 700 Mly, and LEDA 2096860, which may also be a LIRG as it is nearly 15 times brighter in the IR than in the visible band.
The most remote recorded objects by far are two quasars, SDSS J135841.39+373232.3 and SDSS J135859.70+373240.5, whose light is reaching us from the dawn of the Universe. They are respectively 10.9 and 11.2 billion light years distant, and 2,500 and 2,000 times brighter than the Milky. When their photons were emitted, the Solar System would not have come into existence for another 6 billion years. But, from the photons' perspective, travelling at the speed of light time does not pass, and their journey was instantaneous.
Image details:
-Remote Takahashi TOA 150 x 1105mm, Paramount GT GEM
-25 x 300 sec subs, OSC, 2x drizzle, 25% crop
-Software: DSS, XnView, StarNet++, StarTools v 1.3 and 1.7
THE CELESTIAL ZOO is a tour of 210 places of interest in our Universe, describing each landscape with curious facts that are a must-know when planning our trips through the Cosmos. Featuring the most bizarre galaxies, stars, planets, and other weirdos of all colors and shapes. The information contained is updated as of July 2020.
The circular view of the universe in the middle was assembled by Pablo Carlos Budassi by combining logarithmic astronomical maps from Princeton University and images from NASA.
Using this image as a map and the accumulated knowledge of 400 years of modern astronomy, we will spend a couple of minutes in each known world and if we come out alive, we will have the most up-to-date knowledge about the celestial wildlife and maybe, in the next trip, we can be the tour guides ourselves.
Last chance: Take flight or go extinct! ✨✨✨🚀
🔭 GET THE CELESTIAL ZOO HD Poster 👉 bit.ly/thecelestialzooposter
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Genova, Italy (21 Aug 2021 - 01:48 GMT+2)
Orange vintage C8 (203 F10 SC Telescope) on EQ5 Mount
QHY5L-II Color Camera @ F25 (Barlow APO 2.5x)
Recording: SharpCap 4.0 (640x480 @ 58fps - 3min)
Best 4232 frames of 10580 (40%)
Stacking+Wavelets: AstroSurface REDSHIFT-1
Final: GIMP 2.10.8
The 2011 Mobius Wearable Art Runway Show
Friday, May 6 · 7:00pm - 9:00pm - Boston
Created By - Mobius, Inc., Alison Safford, James Ellis Coleman
Program Order and Erratae Mobius Wearable Art 1) Inflatable Metamophosis artist: Charlie Roberts model: Liz Roncka MC talk-introduce the show 2) Liv Chaffee Students -The John Marshall School in Dorchester, MA Deandre Dewhollis, Kyshuari Santana-Everet Jose Pene Rayuana Martin-Milton Xavier Barrietos 3) Marie Ghitman – Two Group Skirts Models: Luke Burrows, Neige Christensen, Sage Dowser, Lisa Hiserodt, Sam Lanier, Jean Martin, Madelyn Medeiros, Jane Messere, Jason Picard, Q, Madelaine Ripley, and Artist 4) Jennifer Hicks - steam punk 5) Amy Keefer (SF) you all know me 6) Katie Pray-zip tease CSW 7) Becky Savitt 8) Ellla Williams- broken Record 9) Ella williams-garbage bag dress 10) Emily D’Angelo – 100% Recyclable 11) Grace Lynn Wilson – Fairy 12) Kaela Cote-Stemmermann - Pagan Sunset 13) Kaela Cote-Stemmermann - Stamp coat, model: Caroline Hickey 14) Mikaela Dalton – Mikaela Dalton – The Devil’s Tune 15) Mikaela Dalton – Untitled (cassette top), Model: Sarah Smith 16) Mikaela Joyce – Bell Jar Dress, Model: Sarah Hertel-Fernandez 17) Mikaela Joyce – Safety Pin Top 18) SeungHye Kim –The Pad Dress 19) Sonya Thorne – Apocalyptic Pieces 1-3, Model: self, Lilia Gaufberg, Zoe Cohen 20) Tess McCabe – Redshift, Model: Molly Harrison 21) William Everston (Representing Seeking Kali) -Sari Scroll for Two, Model: Artist, Karen Everston 22a) Ashley Conchieri – hand Woven and Hand Sewn, Model: Rebecca Chabot 22b) Ashley Conchieri – hand Woven and Hand Sewn, Model: 22c) Ashley Conchieri – hand Woven and Hand Sewn, Model: Monika Plioplyte 23) Julia Dusman – “Tarantula” Necklace 24) Ellen Shea - Little Red Re-Design, Model: Rebecca Woodbury 25) LeeLoo – Fallen post-apocalyptic cyber angel 26) L. Mylott Manning – Insides Out 28) Alyssa Fishenden - Plastic bag and stretch nylon halter dress 29) Robyn Giragosian and Caleb Cole – Pom Prom 30) Rachel Jayson – Dress of sheet music 31) Bethany Haeseler – Fruitloops 32) June Monteiro – “SMARTIE Dress”, Model: Chantal Lima Marquis 33) Jennifer Sherr Designs – Collage and hand painted leather vest, Model: Jess Barnett 34) Stacy A. Scibelli –Sabotage, Models: Meg Kuker, Toni Scibelli 35a) Selina Narov – Silk painted art couture clothing - Model: A. Dorian Rose 35b) Selina Narov – Silk painted art couture clothing - Model: Liz Roncka 35c) Selina Narov – Silk painted art couture clothing - Model: Jennifer Hicks 37) Albert Negredo – RECORDS (word game text) Red dress/Silver bag fabricated by Jane Wang - Model: sara june 38) Stacy A. Scibelli – plated skirt with leather head-piece (Models: tbd) 39) Stephanie Skier – Ephemeral dynamic fiberoptic fiber arts 40) the Bureau of cyberSurreal investigation international webCam Bra for Living I/O Model: Carol Susi 41) Elly Jessop – Glow Dress 42) Raphaela Riepl –Tentacles Flying Teeth, Models: Kira Lorenza Althaler as William Haugh, Florian Maria Sumerauer as Aaron Diskin Finale- 43) Word Game Design Competition Winner: June Monteiro - Model: northern sire
ONLINE BLOG for 2011 Mobius Wearable Art Runway Show: mobius-wearableart2011.blogspot.com/
@ Mobius
725 Harrison Avenue, Suite One
Boston MA 02118
Related Exhibition: A Tool Is A Mirror
NGC 4151 est une galaxie spirale intermédiaire relativement rapprochée et située dans la constellation des Chiens de chasse.
À ce jour, une quinzaine de mesures non basées sur le décalage vers le rouge (redshift) donnent une distance de 31 millions d'al !
NGC 4145 est une galaxie spirale intermédiaire relativement rapprochée et située dans la constellation des Chiens de chasse.
À ce jour, 18 mesures non basées sur le décalage vers le rouge (redshift) donnent une distance de 51,1 millions d'al !
Lunette ASKAR APO120
Caméra ASI2600MC
Monture Ioptron CEM120
Traitement Pixinsight & Photoshop
95 x 240s soit 6H24
Canon Canonet
Fuji Velvia 100F
cross-processed in Tetenal C41 AND bleach bypassed
The latest experiment in bleach bypassing: xpro'd slide film that's also bleach bypassed. Conclusion: there's definitely a little bit of Velvia's characteristic redshift (more like a pinkshift), but mostly it just looks bleach bypassed. Not worth wasting a roll of Velvia on.
#19. The Millennium Simulation, announced 2005.06.02 by the Virgo consortium, used the largest supercomputer in Europe, at the German Astrophysical Virtual Observatory, for over a month to model the history of the Universe in a cube over 2 billion light years on a side, holding 20 million galaxies.
static.flickr.com/13/18135102_07a58fd89d_o.jpg
This image is a closeup of the results at redshift z = 0, showing a 15 MPC/h thick slice, showing the visible light distribution, which closely follows the mass distribution. The view is four times wider than in #18, so that the width of the image is 1628 MLy. The length of the central large and dense galaxy cluster is about 60 MLy.
1024 X 768 pixels jpg 0.970950 MB
The distance measure Mpc/h has been used for decades to adjust to the fact that the Hubble constant = H has not been exactly determined. Mpc is megaparsecs.
A parsec is 3.26 light years. The Millennium Simulation used the value 0.73 for the Hubble constant H.
To get the distance in Mpc, we multiply their value by 100/H = 100/0.73 = 1.37 .
The huge, densely packed galaxy cluster, holding thousands of galaxies, for the greenish central region, has a length of about 60 MLy. In contrast, the nearest large neighbor to our Milky Way galaxy is Andromeda galaxy at 2.2 MLy distance.
The distribution of mass in the Universe is very fractile -- it looks just as complex and very much the same at a very wide range of distance scales.
So, even though I do not know how wide this image would be in terms of angular measures (degrees, minutes, seconds), it is probably justified to compare it to the Capodimonte Deep Field subtle background visible light images.
Many features are the same: complex 3D fractile network, with bright boundaries around both brighter (more dense) and dimmer (more empty) regions, and both brighter and thicker and thinner and dimmer lines, marked by myriad tiny dense features. I don't believe that the MS image includes gravitational lensing, which must be a complex factor in the CDF images.
Click on All Sizes to view Original.
www.pparc.ac.uk/Nw/millennium_sim.asp The Virgo consortium
www.mpa-garching.mpg.de/galform/millennium/
www.mpa-garching.mpg.de/galform/millennium/galseq_D_063.jpg
arxiv.org/abs/astro-ph/0504097
Simulating the joint evolution of quasars, galaxies and their large-scale distribution
pil.phys.uniroma1.it/debate3.html
On the fractile structure of the universe
Sylos Labini, Montuori & Pietronero
#18. The Millennium Simulation, announced 2005.06.02 by the Virgo consortium, used the largest supercomputer in Europe, at the German Astrophysical Virtual Observatory, for over a month to model the history of the Universe in a cube over 2 billion light years on a side, holding 20 million galaxies.
static.flickr.com/12/18135101_1ef7723b85_o.jpg
This image is a closeup of the results at redshift z = 0, showing a 15 MPC/h thick slice, showing the mass distribution, not the visible light.
2048 X 1536 pixels jpg 2.07411 MB
You can magnify this image 8X to see pixels of 1 mm size on a 17" monitor.
The distance measure Mpc/h has been used for decades to adjust to the fact that the Hubble constant = H has not been exactly determined. Mpc is megaparsecs.
A parsec is 3.26 light years. The Millennium Simulation used the value 0.73 for the Hubble constant H.
To get the distance in Mpc, we multiply their value by 100/H = 100/0.73 = 1.37 , which for the scale bar of 31.25 Mpc/h becomes 42.8 Mpc = 139.6 MLy.
This image has a width, directly measured on my monitor, of 91.1 Mpc/h =
124.8 Mpc = 406.9 MLy.
The huge, densely packed galaxy cluster, holding thousands of galaxies, for the greenish central region, has a length of about 2/13.6 = 14.7 % of the image width = 60 MLy. In contrast, the nearest large neighbor to our Milky Way galaxy is Andromeda galaxy at 2.2 MLy distance.
The distribution of mass in the Universe is very fractile -- it looks just as complex and very much the same at a very wide range of distance scales.
So, even though I do not know how wide this image would be in terms of angular measures (degrees, minutes, seconds), it is probably justified to compare it to the Capodimonte Deep Field subtle background visible light images.
Many features are the same: complex 3D fractile network, with bright boundaries around both brighter (more dense) and dimmer (more empty) regions, and both brighter and thicker and thinner and dimmer lines, marked by myriad tiny dense features. I don't believe that the MS image includes gravitational lensing, which must be a complex factor in the CDF images.
Click on All Sizes to view Large and Original.
www.pparc.ac.uk/Nw/millennium_sim.asp The Virgo consortium
www.mpa-garching.mpg.de/galform/millennium/
www.mpa-garching.mpg.de/galform/millennium/seqF_063a.jpg
arxiv.org/abs/astro-ph/0504097
Simulating the joint evolution of quasars, galaxies and their large-scale distribution
pil.phys.uniroma1.it/debate3.html
On the fractile structure of the universe
Sylos Labini, Montuori & Pietronero
www.space.com/scienceastronomy/first_star_011115.html popular article by Robert Roy Britt 2001.11.15 on www.space.com re Tom Abel simulation of the first start in our Universe www.tomabel.com/
www.solstation.com/x-objects/first.htm excellent general introduction to many recent simulations of the first stars -- many links
www.astro.psu.edu/users/tabel/GB/gb.html many awesome images and movies of simulations of the first structures and stars in our Universe by Tom Abel, Greg Bryan, and Mike Norman in 2001
www.astro.psu.edu/users/tabel/GB/gb.html frame by frame tour of the simulation with commentary
www.mpia-hd.mpg.de/GALAXIES/CADIS/irsee2003/PROCEEDINGS/A...
the first stars, a slideshow review by Tom Abel
Compare #21 Closeup of many tiny bright sources on background mesh in HUDF.
By pushing NASA's Hubble Space Telescope to its limits, an international team of astronomers has shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe. This surprisingly bright, infant galaxy, named GN-z11, is seen as it was 13.4 billion years in the past, just 400 million years after the big bang. GN-z11 is located in the direction of the constellation of Ursa Major.
"We've taken a major step back in time, beyond what we'd ever expected to be able to do with Hubble. We see GN-z11 at a time when the universe was only three percent of its current age," explained principal investigator Pascal Oesch of Yale University in New Haven, Connecticut. The team includes scientists from Yale University, the Space Telescope Science Institute (STScI) in Baltimore, Maryland, and the University of California in Santa Cruz, California.
Astronomers are closing in on the first galaxies that formed in the universe. The new Hubble observations take astronomers into a realm that was once thought to be only reachable with NASA's upcoming James Webb Space Telescope.
This measurement provides strong evidence that some unusual and unexpectedly bright galaxies found earlier in Hubble images are really at extraordinary distances. Previously, the team had estimated GN-z11's distance by determining its color through imaging with Hubble and NASA's Spitzer Space Telescope. Now, for the first time for a galaxy at such an extreme distance, the team used Hubble's Wide Field Camera 3 to precisely measure the distance to GN-z11 spectroscopically by splitting the light into its component colors.
Astronomers measure large distances by determining the "redshift" of a galaxy. This phenomenon is a result of the expansion of the universe; every distant object in the universe appears to be receding from us because its light is stretched to longer, redder wavelengths as it travels through expanding space to reach our telescopes. The greater the redshift, the farther the galaxy.
"Our spectroscopic observations reveal the galaxy to be even farther away than we had originally thought, right at the distance limit of what Hubble can observe," said Gabriel Brammer of STScI, second author of the study.
Before astronomers determined the distance for GN-z11, the most distant galaxy measured spectroscopically had a redshift of 8.68 (13.2 billion years in the past). Now, the team has confirmed GN-z11 to be at a redshift of 11.1, nearly 200 million years closer to the time of the big bang. "This is an extraordinary accomplishment for Hubble. It managed to beat all the previous distance records held for years by much larger ground-based telescopes," said investigator Pieter van Dokkum of Yale University. "This new record will likely stand until the launch of the James Webb Space Telescope."
The combination of Hubble's and Spitzer's imaging reveals that GN-z11 is 25 times smaller than the Milky Way and has just one percent of our galaxy's mass in stars. However, the newborn GN-z11 is growing fast, forming stars at a rate about 20 times greater than our galaxy does today. This makes such an extremely remote galaxy bright enough for astronomers to find and perform detailed observations with both Hubble and Spitzer.
The results reveal surprising new clues about the nature of the very early universe. "It's amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon," explained investigator Garth Illingworth of the University of California, Santa Cruz.
These findings provide a tantalizing preview of the observations that the James Webb Space Telescope will perform after it is launched into space in 2018. "Hubble and Spitzer are already reaching into Webb territory," Oesch said. "This new discovery shows that the Webb telescope will surely find many such young galaxies reaching back to when the first galaxies were forming," added Illingworth.
This discovery also has important consequences for NASA's planned Wide-Field Infrared Survey Telescope (WFIRST), which will have the ability to find thousands of such bright, very distant galaxies.
The team's findings will appear in the March 8, 2016, edition of The Astrophysical Journal.