John Bochanski, Ph.D.
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  • Publications
    • Sloan Digital Sky Survey-V: Pioneering Panoptic Spectroscopy
    • The Velocities of T Dwarfs within 20 Parsec of the Sun Measured with Magellan FIRE
    • The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V
    • Better support for collaborations preparing for large-scale projects: the case study of the LSST Science Collaborations
    • SDSS-V Pioneering Panoptic Spectroscopy
    • The Sloan Digital Sky Survey as an Archetypal Mid-Scale Program
    • VizieR Online Data Catalog: Improved & expanded membership catalog for NGC752 (Agueros+, 2018)
    • An example preprint / working paper
    • Dying Stars Make Glowing Serpent
    • Milky Way: Star Pattern Suggests Recent Galactic Whack
    • Exoplanets: Astronomers Weigh Beta Pictoris b
    • Stars: Aurorae Discovered Around Rogue Brown Dwarf
    • VizieR Online Data Catalog: Properties of co-moving stars observed by Gaia (Bochanski+, 2018)
    • New and Known Moving Groups and Clusters Identified in a Gaia Comoving Catalog
    • A New Look at an Old Cluster: The Membership, Rotation, and Magnetic Activity of Low-mass Stars in the 1.3 Gyr Old Open Cluster NGC 752
    • Fundamental Properties of Co-moving Stars Observed by Gaia
    • Stars: New Observations of Boyajian's Star
    • Exoplanets: Ross 128b Orbits Quiet Nearby Star
    • Exoplanets: Cool Dust Discovered Around Proxima Centauri
    • In Brief: New Exomoon Candidate
    • New views of the distant stellar halo
    • Stars: Brown Dwarfs Mimic Stellar Siblings
    • VizieR Online Data Catalog: Proper motions and photometry for members of Cha I (Esplin+, 2017)
    • A Survey for Planetary-mass Brown Dwarfs in the Chamaeleon I Star-forming Region
    • VizieR Online Data Catalog: 05 through L3 empirical stellar spectra from SDSS (Kesseli+, 2017)
    • An Empirical Template Library of Stellar Spectra for a Wide Range of Spectral Classes, Luminosity Classes, and Metallicities Using SDSS BOSS Spectra
    • Stellar: Origin of Our Galaxy's Most Distant Stars
    • VizieR Online Data Catalog: Activity and rotation in Praesepe and the Hyades (Douglas+, 2014)
    • BU-hammerTeam/PyHammer: Release Associated with Kesseli et al. 2017 Publication
    • Galactic: Milky Way's New Neighbor
    • Examining the ages of M7-L8 dwarfs with the BOSS Ultracool Dwarf sample
    • In Brief: Brown Dwarfs Form like Stars
    • VizieR Online Data Catalog: BDKP IV. RVs of late-M and L dwarfs with MagE (Burgasser+, 2015)
    • An example journal article
    • The Brown Dwarf Kinematics Project (BDKP). IV. Radial Velocities of 85 Late-M and L Dwarfs with MagE
    • The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
    • Exoplanets: Gap Reveals Potential Exomoon
    • BOSS Ultracool Dwarfs. I. Colors and Magnetic Activity of M and L Dwarfs
    • In Brief: Stars' Spins Show Their Ages
    • Early Observations and Analysis of the Type Ia SN 2014J in M82
    • Hunting the Most Distant Stars in the Milky Way
    • Rotation and Activity in Praesepe and the Hyades
    • Technology: Next-Gen Adaptive Optics
    • The Factory and the Beehive. II. Activity and Rotation in Praesepe and the Hyades
    • A New Sample of Cool Subdwarfs from SDSS: Properties and Kinematics
    • Maximizing LSST's Scientific Return: Ensuring Participation from Smaller Institutions
    • Near-infrared Detection of WD 0806-661 B with the Hubble Space Telescope
    • Calibrating Ultracool Dwarfs: Optical Template Spectra, Bolometric Corrections, and ensuremathχ Values
    • The Most Distant Stars in the Milky Way
    • A New Sample of Cool Subdwarfs from SDSS: Properties and Kinematics
    • The Hammer: An IDL Spectral Typing Suite
    • Hunting the Most Distant Stars in the Milky Way: Methods and Initial Results
    • Stellar: New Cutoff for Star Sizes
    • The Tenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Apache Point Observatory Galactic Evolution Experiment
    • Detection of an Extrasolar Planet Candidate in Habitable Zone of a Low-Mass Binary
    • Gaia & Ultra-Cool Dwarfs: a high-definition picture of the Milky Way
    • Exoplanets: Alien Dust Trap Finally Detected
    • The Sloan Digital Sky Survey Data Release 7 Spectroscopic M Dwarf Catalog. III. The Spatial Dependence of Magnetic Activity in the Galaxy
    • An example conference paper
    • FIRE: A Facility Class Near-Infrared Echelle Spectrometer for the Magellan Telescopes
    • In Brief: Brown Dwarfs Might Make Planets
    • Exoplanets: New Goldilocks Planet
    • Mapping the Local Halo: Statistical Parallax Analysis of SDSS Low-mass Subdwarfs
    • Measuring the ages of low-mass stars and brown dwarfs
    • Stars: Auroras Grace Dwarf Skies
    • The Very Short Period M Dwarf Binary SDSS J001641-000925
    • Assigning Star-galaxy Probabilities to SDSS Stripe 82 Point Sources
    • First Light: Cameras Open Their Eyes
    • First Results From The BOSS Ultracool Dwarf (BUD) Sample
    • Mapping the Milky Way's Halo out to 500 kpc: New M Giants selected from UKIDSS
    • Measuring the Distribution of Active M Dwarfs in the Galaxy
    • Science Highlights from the SDSS DR7 Spectroscopic M Dwarf Catalog
    • The PTF Open Cluster Survey: Tracking the Evolution of Rotation and Activity on the Lower Main Sequence
    • Using HST Globular Clusters to Derive an Empirical Photometric Metallicity Relation for Low-mass Stars
    • Infrared Monitoring of the Nearest Low-Mass T Tauri Binary: TWA 30AB
    • The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
    • SpIES: The Spitzer-IRAC Equatorial Survey
    • Erratum: ``The Luminosity and Mass Functions of Low-mass Stars in the Galactic Disk. II. The Field'' <A href=``/abs/2010AJ....139.2679B''>(2010, AJ, 139, 2679)</A>
    • Gaseous Material Orbiting the Polluted, Dusty White Dwarf HE 1349-2305
    • The Brown Dwarf Kinematics Project (BDKP): Radial and Rotational Velocities for 50 T dwarfs with FIRE
    • The Properties and Kinematics of a New Sample of Cool Subdwarfs from SDSS
    • Detailed Compositional Analysis of the Heavily Polluted DBZ White Dwarf SDSS J073842.56+183509.06: A Window on Planet Formation?
    • An H-band Spectroscopic Metallicity Calibration for M Dwarfs
    • Refined Metallicity Indices for M Dwarfs Using the SLoWPoKES Catalog of Wide, Low-mass Binaries
    • A New Look At An Old Cluster: Age, Activity, And Rotation In NGC 752
    • A Rotation-Activity Relation for Late-type M Dwarfs
    • Confirmation of One of the Coldest Known Brown Dwarfs
    • Mapping the Stellar Content of the Milky Way with LSST
    • VizieR Online Data Catalog: First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)
    • Constraints on the Universal C IV Mass Density at z åisebox-0.5ex~ 6 from Early Infrared Spectra Obtained with the Magellan FIRE Spectrograph
    • Cool Star Science with the FIRE Spectrograph
    • Determining the Metallicity of Low-Mass Stars and Brown Dwarfs: Tools for Probing Fundamental Stellar Astrophysics, Tracing Chemical Evolution of the Milky Way and Identifying the Hosts of Extrasolar Planets
    • Low-Mass Stars in the Sloan Digital Sky Survey: Galactic Structure, Kinematics, and the Luminosity Function
    • Statistical Parallax Analysis of SDSS M Dwarfs
    • The First Hundred Brown Dwarfs Discovered by the Wide-field Infrared Survey Explorer (WISE)
    • The Sloan Digital Sky Survey Data Release 7 M Dwarf Spectroscopic Catalog
    • FIRE Spectroscopy of the Ultra-cool Brown Dwarf, UGPS J072227.51-054031.2: Kinematics, Rotation and Atmospheric Parameters
    • Discovery of a Companion at the L/T Transition with the Wide-field Infrared Survey Explorer
    • Discovery and Characterization of the Coolest Known Brown Dwarf
    • SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way, and Extra-Solar Planetary Systems
    • Erratum: ``The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III'' <A href=``/abs/2011ApJS..193...29A''>(2011, ApJS, 193, 29)</A>
    • Fire Spectroscopy of Five Late-type T Dwarfs Discovered with the Wide-field Infrared Survey Explorer
    • Accretion of a Terrestrial-like Minor Planet by a White Dwarf
    • FIRE Echelle Spectroscopy of T Dwarfs: Speeds and Spins of the Coldest Brown Dwarfs
    • FIRE Spectroscopy Of The Ultracool Brown Dwarf, UGPS 0722-05
    • High Redshift Science With The FIRE IR Spectrograph At Magellan
    • The Living with a Red Dwarf Program: dM Star Evolution and the Usefulness of Rotation as an Age Indicator
    • Periodic Variability of Low-mass Stars in Sloan Digital Sky Survey Stripe 82
    • The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
    • Discovery of a Candidate for the Coolest Known Brown Dwarf
    • Identification of a Wide, Low-Mass Multiple System Containing the Brown Dwarf 2MASS J0850359+105716
    • The Sloan Digital Sky Survey Data Release 7 Spectroscopic M Dwarf Catalog. I. Data
    • The Sloan Digital Sky Survey Data Release 7 Spectroscopic M Dwarf Catalog. II. Statistical Parallax Analysis
    • MARVELS-1b: A Short-period, Brown Dwarf Desert Candidate from the SDSS-III Marvels Planet Search
    • ACCOLADES: Astrometric Changes in Column Overlaps for Low-mass Archaic Dwarfs Espied in SDSS
    • Clouds On A Cold Planet: FIRE Spectroscopy Of Ross 458C
    • Confirmation of a Candidate for the Coolest Known Brown Dwarf
    • Mapping Milky Way And Local Volume Structure With LSST
    • NEMESIS: Near Encounters with M-dwarfs from an Enormous Sample and Integrated Simulations
    • The Brown Dwarf Kinematics Project: Radial Velocities of M and L Dwarfs with MagE
    • The Stellar Populations of the Milky Way and Nearby Galaxies with LSST
    • Using the SLoWPoKES Catalog to Study the Spectroscopic Properties and Constrain Empirical Models of M Dwarfs
    • Clouds in the Coldest Brown Dwarfs: Fire Spectroscopy of Ross 458C
    • A Widely Separated, Highly Occluded Companion to the Nearby Low-mass T Tauri Star TWA 30
    • Discoveries from a Near-infrared Proper Motion Survey Using Multi-epoch Two Micron All-Sky Survey Data
    • Resolving Disks and Jets in a New, Benchmark Low-Mass Binary
    • VizieR Online Data Catalog: NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)
    • The FIRE infrared spectrometer at Magellan: construction and commissioning
    • Sloan Low-mass Wide Pairs of Kinematically Equivalent Stars (SLoWPoKES): A Catalog of Very Wide, Low-mass Pairs
    • The Luminosity and Mass Functions of Low-mass Stars in the Galactic Disk. II. The Field
    • The Enigmatic Young, Low-mass Variable TWA 30
    • Spectroscopic Discovery of the Broad-Lined Type Ic Supernova 2010bh Associated with the Low-Redshift GRB 100316D
    • Discovery of an Unusually Blue L Dwarf Within 10 pc of the Sun
    • The Brown Dwarf Kinematics Project: Parallaxes for Southern Low Luminosity Brown Dwarfs
    • Untangling Galactic History in Action Space
    • Connecting the Time Domain Photometry of M Dwarfs with Low-Resolution Spectroscopy
    • Mapping Milky Way and Local Volume Structure With LSST
    • Simulating the Exoplanet Population Seen by LSST
    • Stellar Population Science with LSST
    • The Brown Dwarf Kinematics Project. II. Details on Nine Wide Common Proper Motion Very Low Mass Companions to Nearby Stars
    • The SDSS-III MARVELS Survey: Target Selection
    • The SDSS-III MARVELS Survey: The First Year
    • Untangling Galactic History in Action Space
    • Details On 10 New Wide Common Proper Motion Pairs Containing An Ultracool Dwarf
    • LSST Science Book, Version 2.0
    • MASE: A New Data-Reduction Pipeline for the Magellan Echellette Spectrograph
    • TWA: Case Studies in Disk Evolution, Outflows, and Binary Properties of Young Stars
    • Spectroscopic Study of NSVS RR Lyrae Stars: Preliminary Metallicity Results
    • A Sample of Candidate Radio Stars in First and SDSS
    • M Dwarfs in Sloan Digital Sky Survey Stripe 82: Photometric Light Curves and Flare Rate Analysis
    • The Seventh Data Release of the Sloan Digital Sky Survey
    • Using magnetic activity and Galactic dynamics to constrain the ages of M dwarfs
    • Bridging the Gap: A New Eclipsing M Dwarf Binary, 2MASS 0426+0323
    • Optical and Near-Infrared Spectroscopy of the L Subdwarf SDSS J125637.13-022452.4
    • SEGUE: A Spectroscopic Survey of 240,000 Stars with g = 14-20
    • Short Period Variability Of An M-dwarf In SDSS Stripe-82
    • Wild Rides: The Galactic Orbits of Ultracool Subdwarfs
    • Spectrophotometrically Identified Stars in the PEARS-N and PEARS-S Fields
    • Our Nearest 15 Million Neighbors: The Field Low-Mass Stellar Luminosity and Mass Functions
    • SLoWPoKES: A Catalog of Very Wide, Low-Mass Binary Stars
    • Low Mass Stars and Brown Dwarfs Beyond the Solar Neighborhood
    • M Dwarf Flare Rate Analysis of SDSS Stripe 82
    • Marvels (multi-object Apo Radial Velocity Exoplanet Large-area Survey)Target Selection.
    • Measuring Stellar Ages and the History of the Milky Way
    • On-sky Commissioning and Early Results from the SDSS-III-MARVELS Planet Search
    • Resolved Stellar Populations in the Milky Way
    • The Sdss-iii Multi-object Apo Radial-velocity Exoplanet Large-area Survey (marvels) And Its Early Results
    • Transients and Variable Stars with LSST
    • The Luminosity and Mass Functions of Low-Mass Stars in the Galactic Disk. I. The Calibration Region
    • M dwarfs in the local Milky Way: The field low-mass stellar luminosity and mass functions
    • Two-Micron All-Sky Survey J01542930+0053266: a new eclipsing M dwarf binary system
    • The Sixth Data Release of the Sloan Digital Sky Survey
    • Constraining the Age-Activity Relation for Cool Stars: The Sloan Digital Sky Survey Data Release 5 Low-Mass Star Spectroscopic Sample
    • Exploring the Local Milky Way: M Dwarfs as Tracers of Galactic Populations
    • Galactic M Dwarf Flare Rates
    • Improved Photometric Calibrations for Red Stars Observed with the SDSS Photometric Telescope
    • Our 3 Million Nearest Neighbors: The Field Luminosity and Mass Functions of M Dwarfs from Matched SDSS & 2MASS Observations
    • Stellar SEDs from 0.3 to 2.5 ensuremathμm: Tracing the Stellar Locus and Searching for Color Outliers in the SDSS and 2MASS
    • The Active Lives of M Dwarfs: The Activity, Dynamical and Metallicity Evolution of Most Milky Way Stars
    • The Fifth Data Release of the Sloan Digital Sky Survey
    • Cataclysmic Variables from Sloan Digital Sky Survey. VI. The Sixth Year (2005)
    • Low-Mass Dwarf Template Spectra from the Sloan Digital Sky Survey
    • Exploring the Local Milky Way: M Dwarfs as Tracers of Galactic Populations
    • Improvement in the SDSS Photometric Calibration for Red Stars
    • Measuring the Luminosity Function of Low-Mass Stars with Matched Survey Datasets
    • The Age-Activity Relation for M dwarfs Using 25,000 SDSS Spectra
    • Time Variation in the Magnetic Activity of Cool Stars
    • Using the Galactic Dynamics of M7 Dwarfs to Infer the Evolution of Their Magnetic Activity
    • Erratum: ``Spectroscopic Survey of M Dwarfs within 100 Parsecs of the Sun`` (<A href=''/abs/2005AJ.130.1871B''>AJ, 130, 1871 [2005]</A>)
    • A Catalog of Spectroscopically Selected Close Binary Systems from the Sloan Digital Sky Survey Data Release Four
    • Cataclysmic Variables from Sloan Digital Sky Survey. V. The Fifth Year (2004)
    • Low Mass Template Spectra from SDSS
    • The SDSS/2MASS Low Mass Stellar Luminosity Function: The Calibration Region
    • Spectroscopic Survey of M Dwarfs within 100 Parsecs of the Sun
    • The Ultraviolet, Optical, and Infrared Properties of Sloan Digital Sky Survey Sources Detected by GALEX
    • Cataclysmic Variables from Sloan Digital Sky Survey. IV. The Fourth Year (2003)
    • The Third Data Release of the Sloan Digital Sky Survey
    • A Search for Variability in Cool White Dwarf Stars
    • A Spectroscopic Survey of M Dwarfs within 100 Parsecs of the Sun
    • The Evolution of Low Mass Stars in Close Binary Systems
    • Cataclysmic Variables from the Sloan Digital Sky Survey. III. The Third Year
    • Cataclysmic Variables from SDSS III. The Third Year
    • The Second Data Release of the Sloan Digital Sky Survey
    • A Search for Variability Among Cool Blue Degenerate Stars
    • The First Data Release of the Sloan Digital Sky Survey
    • Cataclysmic Variables from the Sloan Digital Sky Survey. II. The Second Year
    • a Search for Variability in Cool White Dwarf STARS*
    • White Dwarf - M Dwarf Pairs in the Sloan Digital Sky Survey
    • The temporal spectrum of the sdB pulsating star HS 2201+2610 at 2 ms resolution
    • A Search for Variability Among Cool White Dwarf Stars
    • The Mystery Companion of Mira Uncovered
    • When the Sun was Young: A Multi-frequency Study of the Young Solar Analog HD 129333 (= EK Dra)
    • Pre-discovery Photometry of the gamma Doradus-type Pulsating Star HR 8330 (= HD 207223)
    • Starspots on the Young Solar-type Star pi1̂ Ursae Maioris
    • MT Pegasi (= HD 217813) - A Young Sun with Starspots
    • A Possible Brown Dwarf Companion to the Hyades Eclipsing Binary V471 Tauri
    • The Sun in Time: Starspots and Luminosity Variations of the Solar-type Stars of Different Ages
    • Recent Light Curves and Period Study of the Contact Binary W Ursae Majoris
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MT Pegasi (= HD 217813) - A Young Sun with Starspots

Aug 1, 2000·
J.~M. Depasquale
,
E.~F. Guinan
,
J.~J. Bochanski
· 0 min read
Cite
Type
Journal article
Publication
Information Bulletin on Variable Stars
Last updated on Aug 13, 2025
← Starspots on the Young Solar-type Star pi1̂ Ursae Maioris Mar 1, 2001
A Possible Brown Dwarf Companion to the Hyades Eclipsing Binary V471 Tauri May 1, 2000 →

© 2025 John Bochanski. This work is licensed under CC BY NC ND 4.0

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