APOD: IC 4592: The Blue Horsehead Nebula... (2021 Jul 05)

[APOD Robot]

IC 4592: The Blue Horsehead Reflection Nebula

Explanation: Do you see the horse's head? What you are seeing is not the famous Horsehead nebula toward Orion but rather a fainter nebula that only takes on a familiar form with deeper imaging. The main part of the here imaged molecular cloud complex is a reflection nebula cataloged as IC 4592. Reflection nebulas are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars. In this case, the source of much of the reflected light is a star at the eye of the horse. That star is part of Nu Scorpii, one of the brighter star systems toward the constellation of the Scorpion (Scorpius). A second reflection nebula dubbed IC 4601 is visible surrounding two stars to the right of the image center.

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[Ann]

IC 4592: The Blue Horsehead Reflection Nebula. Image Credit & Copyright: Adam Block, Steward Observatory, University of Arizona.

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Water color painting of a space horse. Artist: Telinunu.

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Neigh!!! In space no one can hear the horse's whinny!

APOD Robot wrote:
Reflection nebulas are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars.

Nu Sco... No, sorry, this is actually Rho Ophiuchi, but Nu Sco and Rho Oph are both hot blue stars of spectral class B2, and they are both lighting up reflection nebulas. Image: Wikisky.

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Points of a horse. Illustration: Owain Davies.

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So Nu Sco is painting a part of this cosmic equine blue. What is that part of a horse's face called? Beats me! As you can see in the picture at right, the long stretch of equine face between the forehead and the muzzle appears to be nameless.

Ah, but it's blue!

Ann

[VictorBorun]

What is that part of a horse's face called?
Ann

nose bridge? The nose top thing to support spectacles?

[orin stepanek]

Horse reflection nebula very realistic of a horse! Ed
should like!

Ma! Naughty horsey stuck his tongue out at us!

[De58te]

I'm not an expert on horses but I'd imagine that part between the forelock and the muzzle would be called the bridge of the nose if you are looking at the horse face to face, and the cheek if you are looking at the horse sideways.

[johnnydeep]

I'm not an expert on horses but I'd imagine that part between the forelock and the muzzle would be called the bridge of the nose if you are looking at the horse face to face, and the cheek if you are looking at the horse sideways.

Yeah, that seems right:

Click to view full size image

[johnnydeep]

IC 4592: The Blue Horsehead Reflection Nebula

Explanation: Do you see the horse's head? What you are seeing is not the famous Horsehead nebula toward Orion but rather a fainter nebula that only takes on a familiar form with deeper imaging. The main part of the here imaged molecular cloud complex is a reflection nebula cataloged as IC 4592. Reflection nebulas are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars. In this case, the source of much of the reflected light is a star at the eye of the horse. That star is part of Nu Scorpii, one of the brighter star systems toward the constellation of the Scorpion (Scorpius). A second reflection nebula dubbed IC 4601 is visible surrounding two stars to the right of the image center.

Nu Scorpii is quite a star system! From the WikiPedia page:

Nu Scorpii is a septuple star system.[5] It is one of only two known systems, the other being AR Cassiopeiae. Higher-multiplicity star systems are uncommon because they are less stable than their simpler counterparts, and often decay into smaller systems.

Nu Scorpii is split into two groups, Nu Scorpii AB and Nu Scorpii CD. Nu Scorpii CD is located 41 arcseconds away from Nu Scorpii A, and is also known as HR 6026.[10]

Construction of Nu Scorpii (not to scale)

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[neufer]

Nu Scorpii is quite a star system! From the WikiPedia page:

Nu Scorpii is a septuple star system. It is one of only two known systems, the other being AR Cassiopeiae. Higher-multiplicity star systems are uncommon because they are less stable than their simpler counterparts, and often decay into smaller systems.

Nu Scorpii is split into two groups, Nu Scorpii AB and Nu Scorpii CD. Nu Scorpii CD is located 41 arcseconds away from Nu Scorpii A, and is also known as HR 6026.

Construction of Nu Scorpii (not to scale)

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<<Nu Scorpii bore the traditional name Jabbah, possibly from the Arabic Iklīl al Jabhah ('the crown of the forehead'). In 2016, the IAU's Working Group on Star Names decided to attribute proper names to individual stars. It approved the name Jabbah for the component Nu Scorpii Aa on 30 June 2017.>>

[starsurfer]

I so prefer this north up.