APOD: NGC 1499: The California Nebula (2021 Mar 10)

[APOD Robot]

NGC 1499: The California Nebula

Explanation: Could Queen Calafia's mythical island exist in space? Perhaps not, but by chance the outline of this molecular space cloud echoes the outline of the state of California, USA. Our Sun has its home within the Milky Way's Orion Arm, only about 1,000 light-years from the California Nebula. Also known as NGC 1499, the classic emission nebula is around 100 light-years long. On the featured image, the most prominent glow of the California Nebula is the red light characteristic of hydrogen atoms recombining with long lost electrons, stripped away (ionized) by energetic starlight. The star most likely providing the energetic starlight that ionizes much of the nebular gas is the bright, hot, bluish Xi Persei just to the right of the nebula. A regular target for astrophotographers, the California Nebula can be spotted with a wide-field telescope under a dark sky toward the constellation of Perseus, not far from the Pleiades.

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[SpaceCadet]

Is Xi Persei in the photo? There are a number of blue stars here so I can't tell which one it is.

[Knight of Clear Skies]

Is Xi Persei in the photo? There are a number of blue stars here so I can't tell which one it is.

Pretty sure Xi Persei is the bright star on the right. I believe it's a runaway star which just happens to be passing, and is responsible for lighting up the nebula. In IR it's possible to see the bow-shock caused by the star.

https://en.wikipedia.org/wiki/Californi ... Nebula.jpg

[orin stepanek]

With the high coloration; the California Nebula is very neat!

[johnnydeep]

It's amusing to me that none of the six pics of this nebula at the WikiPedia page for it look anything like California, at least not how California is normally portrayed.

[Chris Peterson]

It's amusing to me that none of the six pics of this nebula at the WikiPedia page for it look anything like California, at least not how California is normally portrayed. :ssmile:

I'd say the fourth one does. As does today's image.

[johnnydeep]

It's amusing to me that none of the six pics of this nebula at the WikiPedia page for it look anything like California, at least not how California is normally portrayed.

I'd say the fourth one does. As does today's image.

More like Nova Scotia:

Click to view full size image

[orin stepanek]

I think today's look like California!

[Deathfleer]

Is there just molecules and no particles in the cloud. If so, what is the density and the size of the particles in the cloud.

[E Fish]

That is an absolutely gorgeous picture today. The colors are beautiful and I love all the details that can be seen in the nebula.

[johnnydeep]

Is there just molecules and no particles in the cloud. If so, what is the density and the size of the particles in the cloud.

Despite how they may look from afar, nebulae are not dense at all! From https://en.wikipedia.org/wiki/Nebula

A nebula (Latin for 'cloud' or 'fog';[2] pl. nebulae, nebulæ or nebulas[3][4][5][6]) is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, the term was used to describe any diffused astronomical object, including galaxies beyond the Milky Way. The Andromeda Galaxy, for instance, was once referred to as the Andromeda Nebula (and spiral galaxies in general as "spiral nebulae") before the true nature of galaxies was confirmed in the early 20th century by Vesto Slipher, Edwin Hubble and others.

Most nebulae are of vast size; some are hundreds of light-years in diameter. A nebula that is visible to the human eye from Earth would appear larger, but no brighter, from close by.[7] The Orion Nebula, the brightest nebula in the sky and occupying an area twice the angular diameter of the full Moon, can be viewed with the naked eye but was missed by early astronomers.[8] Although denser than the space surrounding them, most nebulae are far less dense than any vacuum created on Earth – a nebular cloud the size of the Earth would have a total mass of only a few kilograms.

From that article, you can click on the links to "interstellar cloud", and then the various components they are made of, like dust, gas and plasma.

[Deathfleer]

Tha area should be active, if not, the plasma cannot last for a long time...?l

[neufer]

Tha area should be active, if not, the plasma cannot last for a long time...?l

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<<Menkib (Arabic for "shoulder"), Xi Persei (ξ Persei, abbreviated Xi Per, ξ Per) is a star in the constellation of Perseus. Based upon parallax measurements taken during the Hipparcos mission, it is approximately 1,200 light-years from the Sun. In Chinese, 卷舌 (Juǎn Shé), meaning Rolled Tongue, refers to an asterism consisting of Xi Persei, Nu Persei, Epsilon Persei, Zeta Persei, Omicron Persei and 40 Persei. Consequently, the Chinese name for Xi Persei itself is 卷舌三 (Juǎn Shé sān, "the Third Star of Rolled Tongue").

Menkib has a mass of some 30 solar masses and a surface temperature of 35,000 kelvins, making it one of the hottest stars that can be seen with the naked eye. The fluorescence of the California Nebula (NGC 1499) is due to this star's prodigious radiation.

Xi Persei has an apparent magnitude of +4.06 and is classified as a blue giant (spectral class O7.5III). It is intrinsically 12,700 times brighter than the Sun with absolute magnitude −5.5 in the V band. If the ultraviolet light and light from other wavelengths that emanates from Menkib is included, its total bolometric luminosity is 263,000 times that of the Sun. It is a member of the Perseus OB2 association of co-moving stars, but may be a runaway star since it is now separated by 200 pc from the association's center and has an unusually high radial velocity.>>