A5033007894- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Species Distribution and Climate Change
- Scientific Computing and Data Management
- Animal and Plant Science Education
- Remote Sensing in Agriculture
- Data Visualization and Analytics
- Insect and Arachnid Ecology and Behavior
- Advanced Vision and Imaging
- Geographic Information Systems Studies
- Satellite Image Processing and Photogrammetry
- Genetics, Bioinformatics, and Biomedical Research
- Data Analysis with R
- Interdisciplinary Research and Collaboration
- Research Data Management Practices
- Big Data and Business Intelligence
- History and Developments in Astronomy
- Data Mining Algorithms and Applications
- Astrophysics and Cosmic Phenomena
- Scientific Research and Discoveries
- Plant and animal studies
- Image Processing and 3D Reconstruction
Johns Hopkins University
2010-2022
Brown University
2002-2013
Southern Illinois University Edwardsville
2013
University of Oxford
2013
Board of the Swiss Federal Institutes of Technology
2013
Bronx Health Link
2010
In order to understand the formation and subsequent evolution of galaxies one must first distinguish between two main morphological classes massive systems: spirals early-type systems. This paper introduces a project, Galaxy Zoo, which provides visual classifications for nearly million galaxies, extracted from Sloan Digital Sky Survey (SDSS). achievement was made possible by inviting general public visually inspect classify these via internet. The project has obtained more than 4 × 107...
Morphology is a powerful indicator of galaxy’s dynamical and merger history. It strongly correlated with many physical parameters, including mass, star formation history the distribution mass. The Galaxy Zoo project collected simple morphological classifications nearly 900 000 galaxies drawn from Sloan Digital Sky Survey, contributed by hundreds thousands volunteers. This large number allows us to exclude classifier error, measure influence subtle biases inherent in classification. paper...
We present the data release for Galaxy Zoo 2 (GZ2), a citizen science project with more than 16 million morphological classifications of 304 122 galaxies drawn from Sloan Digital Sky Survey (SDSS). Morphology is powerful probe quantifying galaxy's dynamical history; however, automatic morphology (either by computer analysis images or using other physical parameters as proxies) still have drawbacks when compared to visual inspection. The large number available in current surveys makes...
We analyse the relationships between galaxy morphology, colour, environment and stellar mass using data for over 105 objects from Galaxy Zoo, largest sample of visually classified morphologies yet compiled. conclusively show that colour morphology fractions are very different functions environment. Both sensitive to mass. However, at fixed mass, while is also highly environment, displays much weaker environmental trends. Only a small part both morphology–density colour–density relations can...
We investigate a class of rapidly growing emission line galaxies, known as ‘Green Peas’, first noted by volunteers in the Galaxy Zoo project because their peculiar bright green colour and small size, unresolved Sloan Digital Sky Survey imaging. Their appearance is due to very strong optical lines, namely [O iii]λ5007 Å, with an unusually large equivalent width up ∼1000 Å. discuss well-defined sample 251 colour-selected objects, most which are strongly star forming, although there some active...
The Galaxy Zoo citizen science website invites anyone with an Internet connection to participate in research by classifying galaxies from the Sloan Digital Sky Survey. As of April 2009, more than 200,000 volunteers had made 100 million galaxy classifications. In this paper, we present results a pilot study into motivations and demographics volunteers, define technique determine free responses that can be used larger multiple-choice surveys similar populations. Our categories form basis for...
We report the discovery of an unusual object near spiral galaxy IC 2497, discovered by visual inspection Sloan Digital Sky Survey (SDSS) as part Galaxy Zoo project. The object, known Hanny's Voorwerp, is bright in SDSS g band due to unusually strong OIII 4959-5007 emission lines. present results first targeted observations optical, UV and X-ray, which show that contains highly ionized gas. Although line ratios are similar extended emission-line regions luminous AGN, source this ionization...
We study the spectroscopic properties and environments of red spiral galaxies found by Galaxy Zoo project. By carefully selecting face-on, disk dominated spirals we construct a sample truly passive disks (not dust reddened, nor old stellar populations in bulge). As such, our represent an interesting set possible transition objects between normal blue early types. use SDSS data to investigate physical processes which could have turned these without disturbing their morphology. Red prefer...
We analyze the environmental dependence of galaxy morphology and colour with two-point clustering statistics, using data from Galaxy Zoo, largest sample visually classified morphologies yet compiled, extracted Sloan Digital Sky Survey. present correlation functions spiral early-type galaxies, we quantify between environment marked functions. These yield clear precise trends across a wide range scales, analogous to similar measurements colours, indicating that Zoo classifications themselves...
We use data from the Sloan Digital Sky Survey and visual classifications of morphology Galaxy Zoo project to study black hole growth in nearby Universe (z < 0.05) break down AGN host galaxy population by color, stellar mass morphology.We find that at luminosities L[O iii] > 10 40 ergs -1 early-and late-type galaxies is fundamentally different.AGN as a have broad range masses (10 -10 11 M ⊙ ), reside green valley color-mass diagram their central holes median around 6.5 .However, comparing...
Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due large online datasets.To plan projects, it important understand volunteers' motivations for participating.This paper analyzes results from an survey of nearly 11,000 Galaxy Zoo, astronomy citizen science project.Results show that primary motivation a desire contribute scientific research.We encourage other projects study the their volunteers, see whether and how these may be...
Following the study of Darg et al. (2009; hereafter D09a) we explore environments, optical colours, stellar masses, star formation and AGN activity in a sample 3003 pairs merging galaxies drawn from SDSS using visual classifications Galaxy Zoo project. While D09a found that spiral-to-elliptical ratio (major) mergers appeared higher than global galaxy population, no significant differences are between environmental distributions randomly selected control sample. This makes high occurrence...
We report the discovery of a population nearby, blue early-type galaxies with high star formation rates (0.5 < SFR 50 Msun/yr). They are identified by their visual morphology as provided Galaxy Zoo for SDSS DR6 and u-r colour. select volume-limited sample in redshift range 0.02 z 0.05, corresponding to luminosities approximately L* above, colours significantly bluer than red sequence. confirm objects this investigate environmental dependence properties. Blue tend live lower-density...
We present morphological classifications obtained using machine learning for objects in the Sloan Digital Sky Survey DR6 that have been classified by Galaxy Zoo into three classes, namely early types, spirals and point sources/artefacts. An artificial neural network is trained on a subset of human eye, we test whether machine-learning algorithm can reproduce rest sample. find success matching depends crucially set input parameters chosen algorithm. The colours associated with profile fitting...
We present the largest, most homogeneous catalogue of merging galaxies in nearby universe obtained through Galaxy Zoo project - an interface on world-wide web enabling large-scale morphological classification visual inspection images from Sloan Digital Sky Survey (SDSS). The method converts a set visually-inspected classifications for each galaxy into single parameter (the `weighted-merger-vote fraction,' $f_m$) which describes our confidence that system is part ongoing merger. describe how...
We re-examine the evidence for a violation of large-scale statistical isotropy in distribution projected spin vectors spiral galaxies. have sample $\sim 37,000$ galaxies from Sloan Digital Sky Survey, with their line sight direction confidently classified by members public through online project Galaxy Zoo. After establishing and correcting certain level bias our handedness results we find winding sense to be consistent isotropy. In particular no significant dipole signal, thus overall...
We investigate the effect of dust on spiral galaxies by measuring inclination-dependence optical colours for 24,276 well-resolved SDSS visually classified in Galaxy Zoo. find clear trends reddening with inclination which imply a total extinction from face-on to edge-on 0.7, 0.6, 0.5 and 0.4 magnitudes ugri passbands. split sample into "bulgy" (early-type) "disky" (late-type) spirals using fracdeV (or f_DeV) parameter show that average colour is redder than spirals. This shows observed galaxy...
We present a study of local post-starburst galaxies (PSGs) using the photometric and spectroscopic observations from Sloan Digital Sky Survey results Galaxy Zoo project. find that majority our PSG population have neither early- nor late-type morphologies but occupy well-defined space within colour–stellar mass diagram, most notably, low-mass end ‘green valley’ below transition thought to be division between star-forming high-mass passively evolving bulge-dominated galaxies. Our analysis...
Volcanic activity away from plate boundaries occurs in a variety of settings. Linear, age‐progressive volcanic chains have been explained as the manifestation fixed hot spots, possibly generated by plumes originating deep mantle. However, important examples oceanic intraplate volcanism cannot be this way, including short‐lived and violating predicted age‐distance behavior. Furthermore, significant fraction does not occur linear chains, observations suggest control lithosphere structure many...
Galaxy Zoo is the first study of nearby galaxies that contains reliable information about spiral sense rotation galaxy arms for a sizeable number galaxies. We measure correlation function spin chirality (the in which appear to be spinning) face-on angular, real and projected spaces. Our results indicate hint positive at separations less than ~0.5 Mpc statistical significance 2-3 sigma. This experimental evidence chiral spins. Within tidal torque theory it indicates inertia tensors are...
The SkyServer is an Internet portal to the Sloan Digital Sky Survey Catalog Archive Server. From 2001 2006, there were a million visitors in 3 sessions generating 170 Web hits, 16 ad-hoc SQL queries, and 62 page views. site currently averages 35 thousand 400 per month. logs are public. We analyzed traffic by duration, usage pattern, data product, client type (mortal or bot) over time. analysis shows (1) site's popularity, (2) educational website that delivered nearly fifty hours of...
The Zooniverse projects turn everyday people into “citizen scientists” who work online with real data to assist scientists in conducting research on a variety of topics related galaxies, exoplanets, lunar craters, and solar flares, among others. This paper describes our initial study assess the conceptual knowledge reasoning abilities citizen participating two projects: Galaxy Zoo Moon Zoo. In order measure their abilities, we developed new assessment instruments, Astronomical Concept Survey...
Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due large online datasets. To plan projects, it important understand volunteers' motivations for participating. This paper analyzes results from an survey of nearly 11,000 Galaxy Zoo, astronomy citizen science project. Results show that primary motivation a desire contribute scientific research. We encourage other projects study the their volunteers, see whether and how these may be...