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Caldwell 38
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NGC 4565 (also Needle Galaxy, Caldwell 38, MCG 4-30-6, UGC 7772 and PGC 42038) is a magnitude +9.6 spiral galaxy located 53 ±4 million light-years away in the constellation Coma Berenices. 

The galaxy was discovered by German-British astronomer William Herschel using a 47.5 cm (18.7 inch) f/13 speculum reflector at Datchet, Berkshire, on the 6th April 1785.

Right Ascension 12h 36m 20.8s, Declination +25° 59' 16"

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RE: NGC4565
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Title: HALOGAS: HI Observations and Modelling of the Nearby Edge-on Spiral Galaxy NGC 4565
Authors: Laura K. Zschaechner, Richard J. Rand, George H. Heald, Gianfranco Gentile, Gyula Jňzsa

We present 21-cm observations and models of the neutral hydrogen in NGC 4565, a nearby, edge-on spiral galaxy, as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. These models provide insight concerning both the morphology and kinematics of HI above, as well as within, the disk. NGC 4565 exhibits a distinctly warped and asymmetric disk with a flaring layer. Our modelling provides no evidence for a massive, extended HI halo. We see evidence for a bar and associated radial motions. Additionally, there are indications of radial motions within the disk, possibly associated with a ring of higher density. We see a substantial decrease in rotational velocity with height above the plane of the disk (a lag) of -40 +5/-20 km/s/kpc and -30 +5/-30 km s/kpc in the approaching and receding halves, respectively. This lag is only seen within the inner ~4.75' (14.9 kpc) on the approaching half and ~4.25' (13.4 kpc) on the receding, making this a radially shallowing lag, which is now seen in the HI layers of several galaxies. When comparing results for NGC 4565 and those for other galaxies, there are tentative indications of high star formation rate per unit area being associated with the presence of a halo. Finally, HI is found in two companion galaxies, one of which is clearly interacting with NGC 4565.

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Title: The dust energy balance in the edge-on spiral galaxy NGC 4565
Authors: Ilse De Looze, Maarten Baes, George J. Bendo, Laure Ciesla, Luca Cortese, Gert De Geyter, Brent Groves, Médéric Boquien, Alessandro Boselli, Lena Brondeel, Asantha Cooray, Steve Eales, Jacopo Fritz, Frédéric Galliano, Gianfranco Gentile, Karl G. Gordon, Sacha Hony, Ka H. Law, Suzanne C. Madden, Marc Sauvage, Matthew W. L. Smith, Luigi Spinoglio, Joris Verstappen

We combine new dust continuum observations of the edge-on spiral galaxy NGC 4565 in all Herschel/SPIRE (250, 350, 500 micron) wavebands, obtained as part of the Herschel Reference Survey, and a large set of ancillary data (Spitzer, SDSS, GALEX) to analyse its dust energy balance. We fit a radiative transfer model for the stars and dust to the optical maps with the fitting algorithm FitSKIRT. To account for the observed UV and mid-infrared emission, this initial model was supplemented with both obscured and unobscured star-forming regions. Even though these star-forming complexes provide an additional heating source for the dust, the far-infrared/submillimetre emission long wards of 100 micron is underestimated by a factor of 3-4. This inconsistency in the dust energy budget of NGC 4565 suggests that a sizable fraction (two-thirds) of the total dust reservoir (Mdust ~ 2.9e+8 solar masses) consists of a clumpy distribution with no associated young stellar sources. The distribution of those dense dust clouds would be in such a way that they remain unresolved in current far-infrared/submillimetre observations and hardly contribute to the attenuation at optical wavelengths. More than two-thirds of the dust heating in NGC 4565 is powered by the old stellar population, with localized embedded sources supplying the remaining dust heating in NGC 4565. The results from this detailed dust energy balance study in NGC 4565 is consistent with that of similar analyses of other edge-on spirals.

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Hubble Sees the Needle Galaxy, Edge-on and Up Close

667496main1_needle670.JPG

This image snapped by the NASA/ESA Hubble Space Telescope reveals an exquisitely detailed view of part of the disc of the spiral galaxy NGC 4565. This bright galaxy is one of the most famous examples of an edge-on spiral galaxy, oriented perpendicularly to our line of sight so that we see right into its luminous disc. NGC 4565 has been nicknamed the Needle Galaxy because, when seen in full, it appears as a very narrow streak of light on the sky.
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NGC 4565
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An astronomer from Weymouth has scooped picture of the month in the BBC magazine Sky at Night.
Rob Hodgkinson gained the accolade in the world's first astronomy magazine with his shot of the galaxy NGC 4565, also known as the Needle Galaxy for its narrow profile.

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Spiral Galaxy NGC 4565


Full Res (JPEG): 2048x2397 - 4.7M image.

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The spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile. It lies in the constellation Coma Berenices.


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This sharp colour image reveals the galaxy's bulging central core dominated by light from a population of older, yellowish stars.
The core is dramatically cut by obscuring dust lanes which lace NGC 4565's thin galactic plane.
The galaxy is similar to our own Milky Way Galaxy.
NGC 4565 is only about 30 million light-years distant, but over 100,000 light-years in diameter.

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