Starship Asterisk*

The Tulip and Cygnus X-1

Explanation: This tall telescopic field of view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula, the brightest glowing cloud of interstellar gas and dust above center is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. Nearly 70 light-years across the complex and beautiful Tulip Nebula blossoms about 8,000 light-years away, shown in a Hubble palette image that maps the glow of the nebula's sulfur, hydrogen, and oxygen ions into red, green, and blue colors. Ultraviolet radiation from young energetic stars at the edge of the Cygnus OB3 association, including O star HDE 227018, ionizes the atoms and powers the emission from the Tulip Nebula. Also in the field of view is microquasar Cygnus X-1, one of the strongest X-ray sources in planet Earth's sky. Driven by powerful jets from a black hole accretion disk, its fainter bluish curved shock front is only just visible though, directly above the cosmic Tulip's petals near the top of the frame.

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This is the kind of APOD that almost demands annotation!


Ann

Interestingly, Cygnus X-1 appears to be, well, relatively nearby. The Gaia parallax of the visible component, HD 226868, is 0.4218 milliarcseconds, according to Gaia. This translates as a distance of around 2370 light-years.

The Tulip Nebula, by contrast, is so very much further away, according to today's caption. The distance to the Tulip Nebula is said to be around 8,000 light-years. That doesn't look right, in my opinion, because I think the Tulip Nebula doesn't look as if it was 6,000 light-years further away than Cygnus X-1. And it would be very much of a coincidence if a remarkable high-mass binary with a black hole and an impressive nebula were seen right next to one another in the sky, but with a separation of 6,000 light-years between them.


(All right, all right, it happens that two remarkable deep-sky objects are seen next to one another in the sky, but with a separation between them of thousands of light-years. Michel Lakos' fine RGB picture of NGC 3603 and NGC 3576, the Statue of Liberty nebula, shows that the former is rather orange in color, whereas the Statue of Liberty nebula is more magenta. The orange color of NGC 3603 is an effect of dust reddening caused by a greater distance, and NGC 3603 is by far the more distant object of the two.)

Back to the Tulip Nebula and Cygnus X-1. Would you believe it, Simbad said that the parallax of the ionizing star of the Tulip Nebula, HD 227018, is 0.4750 milliarcseconds! Almost the same as the parallax of HD 226868, except it is a little larger, so that the ionizing star of the Tulip Nebula appears to be even closer! Its distance appears to be around 2,100 light-years!

Maybe it's time to abandon the idea that the Tulip Nebula is 8,000 light-years away?

Ann

Hi Ann!
The Cygnus x-1 link (Chandra Nasa) says the best measurement they have puts it at 6070 light years distant.
https://chandra.harvard.edu/photo/2011/cygx1/

Eric

Several Google searches including Wikipedia state the Tulip Nebula is about 6,000 ly away. Along with what XgeoX said, that puts Cygnus x-1 and the Tulip in close proximity. (Assuming in astronomy that 70 ly is relatively close.)

I like Ann's annotation! I was looking at the monster cloud below for X-1; and than it says

APOD just visible though, directly above the cosmic Tulip's petals

De58te wrote: ↑Thu Jul 29, 2021 11:07 am
Several Google searches including Wikipedia state the Tulip Nebula is about 6,000 ly away. Along with what XgeoX said, that puts Cygnus x-1 and the Tulip in close proximity. (Assuming in astronomy that 70 ly is relatively close.)

• Apparently, they have long been considered companions...just a little closer to us now than before:

https://apod.nasa.gov/apod/ap070524.html wrote:

Astronomy Picture of the Day : 2007 May 24

Explanation: This expansive (1-degree wide) telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. It is centered on a bright hydrogen emission region recorded in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant the nebula is popularly known as the Tulip Nebula, understandably not the only cosmic cloud to evoke the imagery of flowers. Complex and beautiful in visible light, the area also includes one of the brightest, most famous sources in the x-ray sky, Cygnus X-1. Discovered in the early 1970s, Cygnus X-1 is a bizarre binary system consisting of a massive, hot, supergiant star (seen here) in close orbit with a stellar mass black hole. The Cygnus X-1 system is also estimated to lie a comfortable 8,000 light-years away.

Beautiful picture today. The tulip, to me, looks like a tulip with astounding color. Then I see a bunny, facing the right edge, and below that a donkey. I choose donkey rather than horse due to the length of the eyes to nose being shorter than on a horse, IMO.

Bill Bixby

Without searching first, my first guess at Cygnus X-1 and the "bluish shock front" it caused is the indicated star to the left and the smaller blue arc:


But I'm probably wrong. ...EDIT: yup, I'm wrong. As Ann said, it's the star indicated on the right, which is confirmed by this:

Now, where is the bluish shock front? Is it the larger arc in my pic?

<sigh> editing posts with attachments is fraught with peril...

Ann wrote: ↑Thu Jul 29, 2021 5:00 am This is the kind of APOD that almost demands annotation!
Tulip Nebula Cyg X 1 annotated.png

Ann

Yup. Cyg X-1 is also TYC 2678-791-1, and a whole slew of other identifiers.
_

Chris Peterson wrote: ↑Thu Jul 29, 2021 8:49 pm

Ann wrote: ↑Thu Jul 29, 2021 5:00 am This is the kind of APOD that almost demands annotation!
Tulip Nebula Cyg X 1 annotated.png

Ann

Yup. Cyg X-1 is also TYC 2678-791-1, and a whole slew of other identifiers.
_
sh2_101_04_Annotated1_crop.jpg

How did you get Simbad to produce those annotations? Your link only gets me to the Cygnus X-1 data page.

johnnydeep wrote: ↑Thu Jul 29, 2021 9:07 pm

Chris Peterson wrote: ↑Thu Jul 29, 2021 8:49 pm

Ann wrote: ↑Thu Jul 29, 2021 5:00 am This is the kind of APOD that almost demands annotation!
Tulip Nebula Cyg X 1 annotated.png

Ann

Yup. Cyg X-1 is also TYC 2678-791-1, and a whole slew of other identifiers.
_
sh2_101_04_Annotated1_crop.jpg

How did you get Simbad to produce those annotations? Your link only gets me to the Cygnus X-1 data page.

The annotations were provided by PixInsight, a tool I own. It plate solved the APOD and then overlaid it with the objects of my choice, in this case the Tycho catalog, since that cross-references with Cyg X-1.

Chris Peterson wrote: ↑Thu Jul 29, 2021 9:53 pm

johnnydeep wrote: ↑Thu Jul 29, 2021 9:07 pm

Chris Peterson wrote: ↑Thu Jul 29, 2021 8:49 pm

Yup. Cyg X-1 is also TYC 2678-791-1, and a whole slew of other identifiers.
_
sh2_101_04_Annotated1_crop.jpg

How did you get Simbad to produce those annotations? Your link only gets me to the Cygnus X-1 data page.

The annotations were provided by PixInsight, a tool I own. It plate solved the APOD and then overlaid it with the objects of my choice, in this case the Tycho catalog, since that cross-references with Cyg X-1.

Wow - nice tool!

johnnydeep wrote: ↑Thu Jul 29, 2021 10:37 pm

Chris Peterson wrote: ↑Thu Jul 29, 2021 9:53 pm

johnnydeep wrote: ↑Thu Jul 29, 2021 9:07 pm

How did you get Simbad to produce those annotations? Your link only gets me to the Cygnus X-1 data page.

The annotations were provided by PixInsight, a tool I own. It plate solved the APOD and then overlaid it with the objects of my choice, in this case the Tycho catalog, since that cross-references with Cyg X-1.

Wow - nice tool!

It is... especially as plate solving and annotation are only one microscopic little corner of its features.

Chris Peterson wrote: ↑Thu Jul 29, 2021 10:44 pm

johnnydeep wrote: ↑Thu Jul 29, 2021 10:37 pm

Chris Peterson wrote: ↑Thu Jul 29, 2021 9:53 pm

The annotations were provided by PixInsight, a tool I own. It plate solved the APOD and then overlaid it with the objects of my choice, in this case the Tycho catalog, since that cross-references with Cyg X-1.

Wow - nice tool!

It is... especially as plate solving and annotation are only one microscopic little corner of its features.

Wow²! At pixinsight.com, one can try it free for 45 days, and a commercial license is only 230 Euros. Pretty reasonable. If I was more than a dabbler in astronomy I’d probably buy it.

johnnydeep wrote: ↑Thu Jul 29, 2021 10:51 pm

Chris Peterson wrote: ↑Thu Jul 29, 2021 10:44 pm

johnnydeep wrote: ↑Thu Jul 29, 2021 10:37 pm

Wow - nice tool!

It is... especially as plate solving and annotation are only one microscopic little corner of its features.

Wow²! At pixinsight.com, one can try it free for 45 days, and a commercial license is only 230 Euros. Pretty reasonable. If I was more than a dabbler in astronomy I’d probably buy it.

It's a great value, particularly as it does not follow the subscription model of software that is so popular these days. You buy it, you have a lifetime license, across multiple machines, and all future updates. I mostly ignore software these days that requires regular payments to maintain.

It has a pretty steep learning curve, and marginal documentation (although they are working on improving that). Its entire structure and interface is... odd, to say the least. They try to make a case for it, but I'm not entirely convinced. Still, once you get used to its strange interface, it's incredibly powerful- leaps and bounds beyond any other astronomical image processing tools out there.

“It's a great value, particularly as it does not follow the subscription model of software that is so popular these days. You buy it, you have a lifetime license, across multiple machines, and all future updates. I mostly ignore software these days that requires regular payments to maintain.”

I couldn’t agree more Chris!

Eric