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Hubble Science BriefingThe “Monkey’s Tooth?” Hubble’s new infrared view of a star-forming pillarApril 3, 2014Zolt Levay ・ Hubble Heritage STScI

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NGC 2174Hubble’s 24th Anniversary

Choosing the target Context, nomenclature Observation planning Observation timeline Data Image features

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Hubble’s Hidden Treasures

WFPC2 2001

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Location on the sky

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Zoom in to NGC 2174

Digitized Sky Survey red+blue

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Star-forming cloud NGC 2174

NGC 2175Open (galactic) cluster

NGC 2174HII (ionized) region

Digitized Sky Survey red+blue

SH 2-252

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The monkey head?

Photo: J-P Metsavainio

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The monkey head?

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The monkey’s tooth?

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Visible — WFPC2 — 2001

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Infrared — WFC3 — 2014

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Visible vs. IR

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Observation planning

Orbits Pointing/mosaic Instruments,

filters Exposure time

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Observation planning — pointing

WFC3/IR

ACS/WFCparallel

Astronomer’s Proposal Tool (APT), Aladin

Digitized Sky Survey (DSS) image

2x2 mosaic

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Observation planning — filters

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Observation planning — visibilityAstronomer’s Proposal Tool (APT)

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Observation planning — orbitAstronomer’s Proposal Tool (APT)

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Data — first visits

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Data — F105W mosaic

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Data — replacement visits

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Data — replacement tiles

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Data — mosaics

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Apply color

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Color composite

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Name: NGC 2174-75, Monkey Head Nebula, Sharpless 2-252 (refers to larger nebula)

Constellation: Orion Coordinates: R.A. 06h 09m 10s, Dec. +20°

27′20″ Distance: 6,400 light-years, 2 kiloparsecs

(~5x M42) Instrument: HST WFC3/IR Observation date: February 7-24, 2014 Wavelength: 1,050-1,600 nm (1.05-1.60

μm) Exposure: 25-35 min./filter/pointing

Factoids

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Image features — detail

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Image features — detail

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Image features

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Distinctive features in the image

• Many more stars are apparent in the IR• Several small knots (red markers) are seen completely or nearly

separated from the main body of the pillar feature. As the gas and dust are eroded and evaporated from the nebula, denser areas remain as islands, some of which may have enough density to collapse into stars.

• At the top of one of the sub-pillars there appears to be a proto-stellar jet (yellow marker), the signature of early star formation. Jets appear in many star-forming regions such as this, sometimes apparent in visible light, sometimes only appearing in the IR. Higher resolution (JWST) imaging or spectroscopy would be needed to confirm that this is a jet.

• Many galaxies (green markers) appear in the IR image, which are totally obscured in visible light. We can conclude that this region of space is much more transparent at infrared wavelengths.

• Filaments of gas (blue markers) appear to be streaming from the surface of the denser portion of the pillar. The hot stars sculpting the material are heating and evaporating the gas and dust at the surface, and this material is moving away from the denser material, possibly under the influence of magnetic fields.

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Hubble HeritageZolt Levay

Carol ChristianLisa FrattareMario Livio

Jennifer MackMax MutchlerShelly Meyett

Keith NollJosh Sokol