I'm a Professor of Astrophysics in the astrophysics group within the Department of Physics & Astronomy (joint 7th in RAE 2008) at Sheffield University (10th in the UK from ARWU 2011). My primary research interests involve studies of Massive Stars in the Milky Way and other star-forming galaxies, for which I have published over 120 ADS refereed and 100 ADS non-refereed papers, including an Annual Review article on the properties of Wolf-Rayet stars and co-authored a monograph From Luminous Hot Stars to Starburst Galaxies for Camb. Univ. Press. My current lecture courses involve Stellar Atmospheres, Stellar Evolution and the Interstellar Medium. Undergraduate 3rd and 4th year projects are closely related to my research interests, e.g. Wolf-Rayet database assembled by two M.Phys students. See also stars just got bigger ESO Press Release from Jul 2010 (see FAQ and Deep Sky Videos film about R136a1) and a review of the Birth, Life and Death of Massive Stars for Astronomy & Geophysics from Aug 2012 (view pdf).

• From Luminous Hot Stars to Starburst Galaxies Co-author (Camb. Astrophys. Ser, Vol. 45) - see list of corrections
• IAU Symp 250: Massive Stars as Cosmic Engines Co-editor (Camb. Univ. Press) and co-chair of Symposium SOC
• Hot Star Workshop III: The Earliest Stages of Massive Star Birth Editor (Astro. Soc. Pac. Conf Ser. Vol 267)

• Four Decades of Research on Massive Stars Workshop in honour of Tony Moffat. Member of SOC (Quebec, Canada, 11-15 Jul 2011)
• Stars for All Invited Speaker (Lund Observatory, Sweden, 6-7 Feb 2012)
• Death of Massive Stars: Supernovae and Gamma-Ray Bursts Invited Speaker (Nikko, Japan, 18-22 April 2011 -> 12-16 Mar 2012)
• Very Massive Stars in the Local Universe Invited Speaker at JD2 at IAU General Assembly (Beijing, China, 20-31 Aug 2012)
• Supernovae illuminating the Universe: from individuals to Populations Contributed speaker (Garching, Germany, 10-14 Sep 2012)
• 30 Doradus: The Starburst Next Door Invited speaker (Baltimore, 17-19 Sep 2012)
• Massive Stars: From Alpha to Omega Invited speaker (Rhodes, Greece, 10-14 Jun 2013)

• HST/Cycle 17: In Search of SNIb/Ic Wolf-Rayet progenitors and comparison with RSG (SN II Progenitors) in the giant ScI spiral M101 (GO 11635, P.I. Mike Shara, 36 orbits)
• VLT/Large Programme: VLT/FLAMES Tarantula Survey (P.I. Chris Evans)
• HST/Cycle 19+20: A Massive Star Census of the Starburst Cluster R136 (GO 12465+13052: P.I. P. Crowther, 32+7 orbits)
• HST/Cycle 19+21: Proper Motions of Massive Stars in 30 Doradus (GO 12499: P.I. D. Lennon, 15+15 orbits)
• HST/Cycle 19: Weighing the most luminous main-sequence star in the Galaxy (GO 12615: P.I. O Schnurr, 14 orbits)
• Herschel/OT2: Oxygen abundances in carbon-type Wolf-Rayet stars from PACS scan spectroscopy (P.I. P Crowther, 7.7 hours)
• HST/Cycle 20+22: Proper motions of isolated massive stars near the Galactic Center (GO 12915, P.I. D. Lennon, 18+18 orbits)

• IC 4663: The first unambiguous [WN] Wolf-Rayet central star of a planetary nebula Miszalski, Crowther, De Marco et al. 2012 MNRAS 423, 934
• The Wolf-Rayet population of the nearby barred spiral galaxy NGC 5068 uncovered by VLT and Gemini Bibby & Crowther 2012, MNRAS 420, 3091
• The G305 star-forming complex: the central star clusters Danks 1 and Danks 2 Davies et al. 2012, MNRAS 419, 1871
• Spectral classification of O2-3.5 If*/WN5-7 stars Crowther & Walborn 2011, MNRAS 416, 1311
• The VLT-FLAMES Tarantula Survey. I. Introduction and observational overview Evans et al. 2011 A&A 300, A108

• Properties of Wolf Rayet Stars ARA&A (2007 Vol 45 p.177-219)

• Hubble's 22nd Anniversary Image Shows Turbulent Star-making Region (STScI, Apr 2012) reported in Big picture: The Tarantula Nebula (BBC Science News)
• Gemini South Reveals First Nitrogen-Sequence Wolf-Rayet Nucleus of a Planetary Nebula (Gemini, Mar 2012)
• Stars just got bigger (ESO, Jul 2010) reported in Astronomers detect monster star' (BBC Science News), Scientists find most massive star ever discovered (Associated Press), Stellar Heavyweight Breaks the Scales (Science NOW), Biggest star ever found may be ticking antimatter bomb (New Scientist), What a scorcher - hotter, heavier and millions of times brighter than the sun (The Guardian), British astronomers discover largest stars (The Times), Astronomers identify star 10 million times brighter than the Sun (The Telegraph), The star that's ten million times brighter than the Sun (The Independent), Giant sun 'largest ever found' (Daily Express), Mon-stars put the sun in the shade (Channel 4 news), R136a1: New Heavyweight Champion? (Sky and Telescope), Most masive star detected (Discovery News) and Star 320 Times Bigger than the Sun Found (Sky News)
• Hubble Catches Heavyweight Runaway Star Speeding from 30 Doradus (HST, May 2010) reported in Fast-moving star is a really big loser (Science News)
• Black Hole Hunters Set New Distance Record (ESO, Jan 2010) reported in 'Farthest' star-mass black hole (BBC Science News)
• Massive Black Hole Smashes Record (NASA, Oct 2007)
• Neutron Star Discovered Where a Black Hole was expected (Chandra, Nov 2005)
• Young And Exotic Stellar Zoo: Super Star Cluster Uncovered in Milky Way (ESO, Mar 2005)

• IAU Working Group on Massive stars. Organizing Ctte Member (2003-present)
• E-ELT UK Design Study Steering Ctte (2009-present)
• TAC member and sub-panel chair for HST Cycle 18 (2010) - details here
• Sub-panel member for Spitzer Cycle 5 (2008)
• Gemini Telescopes. UK National Time Allocation Committee (NTAC) Chair from Semester 08A until 09B, and PATT linked grants panel member.
• Sub-panel member for HST Cycle 16 (2007)
• Isaac Newton Group (ING) board member (2004-2007)
• ESO Observing Proposal Ctte (OPC), member-at-large (2001-2003)

• Birth, life and death of massive stars (Astronomy and Geophysics, vol 53, 4.30-4.36, Aug 2012) - pdf
• A second flavour of Wolf-Rayet CSPNe (Gemini Focus vol 44, Jun 2012)
• The VLT FLAMES Tarantula Survey (ESO Messenger 145, Sep 2011)
• Dissecting the Galactic Super Star Cluster Westerlund 1 - A Laboratory for Stellar Evolution (ESO Messenger 142, Dec 2010)
• Monster Stars: How Big Can They Get? (Astronomy Beat, Nov 2010)
• VLT/FORS surveys of Wolf-Rayet stars beyond the Local Group: Type Ib/c supernova progenitors? ESO Messenger ( 129 Sep 2007)
• Core-collapse supernovae and their massive progenitors (Astronomy & Geophysics, Feb 2007)
• Temperamental Monsters - Massive stars may slim down in eruptive bursts (Science News Online, Sep 2006)

• The public's appetite for astronomy via Nature Blog (21 Dec 2011)
• Physics and Binary Creep via Telescoper (15 Apr 2011)
• The Astronomical Premiership via Telescoper (2 Apr 2011)
• UK space liftoff via The e-Astronomer (21 Mar 2010)
• Life after STFC? via The e-Astronomer (18 Dec 2009)

• Contributor to Cosmic Front (NHK TV) programme about the Magellanic Clouds from 12 Apr 2012 - still
• Contributor to Deep Sky Videos incl. M1 - Crab Nebula, M16 - Eagle Nebula, M42 - Orion Nebula, M45 - Pleiades cluster, M56 - Globular Cluster, M74 - Spiral Galaxy, M76 - Little Dumbbell Nebula, M92 - Globular Cluster M97 - Owl Nebula, Most Massive Star in the Universe, Runaway Star
• Shooting for the Stars from Exposed Magazine, Dec 2011
• Profile from Astronomy and Geophysics, Apr 2011 pdf)

• Website providing updates for professional astronomers.
• Viewpoint: Science cuts 'could lead to brain drain' from BBC Science News on 19 Oct 2010
• Search for a positive signal letter to Times Higher Ed from 4 Feb 2010
• Much left for newly interactive facilities council to do from Research Fortnight on 18 Mar 2009
• Letter to Times Higher Education from May 2008
• Trail of ineptitude from Research Fortnight on 23 Apr 2008,
• An astronomer's view of funding cuts from BBC Science News in Apr 2008
• Dance to the music of stars from Research Fortnight on 20 Feb 2008
• Letter to Guardian from Dec 2007

• `Solar System (Factometer)' by Gaby Goldsack (awaiting publication, Cowley Robinson). Spanish translation: `El sistema solar (Datometer)' (2009, Ediciones SM)