Nebulae in Sagitarrius (Thibault Sandre)

Nebulae in Sagitarrius

Trip to Chile, May 2012

Sagittarius was at zenith, under burning Milky Way.

Thanks to 'lfoastro' for the Borg setup ",

Objects information

Wikipedia The Lagoon Nebula is estimated to be between 4,000-6,000 light years from the Earth. In the sky of Earth, it spans 90' by 40', translates to an actual dimension of 110 by 50 light years. Like many nebulas, it appears pink in time-exposure color photos but is gray to the eye peering through binoculars or a telescope, human vision having poor color sensitivity at low light levels. The nebula contains a number of Bok globules (dark, collapsing clouds of protostellar material), the most prominent of which have been catalogued by E. E. Barnard as B88, B89 and B296. It also includes a funnel-like or tornado-like structure caused by a hot O-type star that emanates ultraviolet light, heating and ionizing gases on the surface of the nebula. The Lagoon Nebula also contains at its centre a structure known as the Hourglass Nebula (so named by John Herschel), which should not be confused with the better known Hourglass Nebula in the constellation of Musca. In 2006 the first four Herbig-Haro objects were detected within the Hourglass, also including HH 870. This provides the first direct evidence of active star formation by accretion within it.

Processing details

Preprocessing using DSS

Bias, darks, flats = average integration ; lights = sigma kipping, kappa=2, iterations=5

Processing using PI

BackgroundNeutralization, ColorCalibration

HistogramTransformation

Masks creation using ATrousWavelets (stars, nebula, LHE masks)

LocalHistogramEqualization (with LHE mask)

Noise reduction (ACDNR with luminance mask, SCNR with no mask)

Saturation boost using Curves (with luminance mask)

HistogramTransform, for last correction

Star size reduction using Morphology

Original
Final
B

	Distinct awarded users	Total awarded images
Image of the day
Top picks
Top pick nominations

	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape

	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown

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Status	Basic failed
Started	...
Astrometry.net job	6438602
PixInsight job	n/a
PixInsight queue size	n/a
PixInsight stage	n/a

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