APOD: Star Formation in the Tadpole Nebula (2020 Jan 28)

[APOD Robot]

Star Formation in the Tadpole Nebula

Explanation: What's all of the commotion in the Tadpole Nebula? Star formation. Dusty emission in the Tadpole Nebula, IC 410, lies about 12,000 light-years away in the northern constellation of the Charioteer (Auriga). The cloud of glowing gas is over 100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the interstellar cloud a mere 4 million years ago, bright newly formed cluster stars are seen all around the star-forming nebula. Notable near the image center are two relatively dense streamers of material trailing away from the nebula's central regions. Potentially sites of ongoing star formation in IC 410, these cosmic tadpole shapes are about 10 light-years long. The featured image was taken in infrared light by NASA's Wide Field Infrared Survey Explorer (WISE) satellite.

<< Previous APOD

This Day in APOD

Next APOD >>

[Ann]

I have never really understood IC 410, which is also known as the Tadpole Nebula. Yes, of course I realize that the "tadpoles" are just another version of "pillars of creation", the tall dust pillars that are sculpted by energetic radiation from young stars born out of a dusty nebula. Well, what I have never understood is where the recently formed young star cluster is, because I have never really been able to "see it" even in photographs!

But I understand things by looking at pictures, so I need to find pictures to make me understand.

Click to view full size image

LRGB photo of the Tadpole nebula (left) and the Flaming Star nebula (right.)
Photo: Alson Wong.

Click to view full size image

Hα, OIII and SII mapped color image of the Tadpole Nebula and the Flame Nebula.
Photo: Sam Saeed.

As you can see from the two pictures above, the Tadpole Nebula (IC 410) and the Flaming Star Nebula (IC 405) look very similar in RGB photography. But in narrowband photography, it becomes obvious that IC 410 is bright in OIII (mapped as blue), and therefore it is much more highly ionized than its seeming "neighbour" IC 405. To be so much more ionized, IC 410 must contain many more hot stars than IC 405, which is just being visited by O9.5V-type star AE Aurigae. And indeed, there are more hot stars in IC 410 than in IC 405.

Click to view full size image

NGC 1893, ionizing cluster of the Tadpole Nebula.
Photo: Bob Franke.

Normally I'm no great fan of narrowband imagery, but I must admit that Bob Franke's very fine narrowband picture of the Tadpole Nebula and cluster NGC 1893 makes the (pink-looking) stars stand out.

So this is the lesson for today. IC 405 (the Flaming Star Nebula) and IC 410 (the Tadpole Nebula) look deceptively similar in RGB imagery, but they are in fact very different. The Flaming Star Nebula is just a cloud of gas and dust being temporarily ionized by runaway star AE Aurigae passing by. IC 410, the Tadpole Nebula, is a bona fide region of massive star formation, and the nebula is highly ionized. The Tadpole Nebula is much farther away than the Flaming Star Nebula too, 12,000 light-years away versus "only" 1,500 light-years for the Flaming Star Nebula.

Click to view full size image

So tadpoles can be more impressive than you think, at least when they come in the form of nebulas!

Ann

[orin stepanek]

Really nice color pallet used on this
nebula!

ic410_WISEantonucci_960.jpg

[neufer]

---

.
Explanation: Dusty emission in the Tadpole Nebula, IC 410, lies about 12,000 light-years away in the northern constellation of the Cheerioteer.

[Ann]

---

.
Explanation: Dusty emission in the Tadpole Nebula, IC 410, lies about 12,000 light-years away in the northern constellation of the Cheerioteer.

Click to play embedded YouTube video.

Dinner for one / Cheerio, Miss Sophie

[sillyworm 2]

The circular structure extreme 3 o'clock...is it a ring galaxy?

[neufer]

The circular structure extreme 3 o'clock...is it a ring galaxy?

The brightest stars are seen as circles with surrounding diffraction rings (i.e., Airy disks).

Reflecting telescopes also produce crisscross diffraction spikes (from secondary mirror supports).

A computer-generated image of an Airy disk. The grayscale intensities have been adjusted to enhance the brightness of the outer rings of the Airy pattern.

---

<<In optics, the Airy disk (or Airy disc) and Airy pattern are descriptions of the best-focused spot of light that a perfect lens with a circular aperture can make, limited by the diffraction of light. The Airy disk is of importance in physics, optics, and astronomy.

The diffraction pattern resulting from a uniformly illuminated, circular aperture has a bright central region, known as the Airy disk, which together with the series of concentric rings around is called the Airy pattern. Both are named after George Biddell Airy. The disk and rings phenomenon had been known prior to Airy; John Herschel described the appearance of a bright star seen through a telescope under high magnification for an 1828 article on light for the Encyclopedia Metropolitana: ...the star is then seen (in favourable circumstances of tranquil atmosphere, uniform temperature, etc.) as a perfectly round, well-defined planetary disc, surrounded by two, three, or more alternately dark and bright rings, which, if examined attentively, are seen to be slightly coloured at their borders. They succeed each other nearly at equal intervals round the central disc....>>

[Chris Peterson]

The circular structure extreme 3 o'clock...is it a ring galaxy?

If you're talking about circles around stars, read Art's comment. If you're talking about the two slightly triangular rings seen on the far right side, I suspect they are some kind of optical artifact, probably filter ghosts (reflections off of internal optics, most likely filters).

[sillyworm 2]

Thanks Had I seen the 2nd identical remnant below I wouldn't have asked.My mistake.