APOD: Symbiotic R Aquarii (2018 Jul 11)

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APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by APOD Robot » Wed Jul 11, 2018 4:06 am

Image Symbiotic R Aquarii

Explanation: You can see it change in brightness with just binoculars over the course of a year. Variable star R Aquarii is actually an interacting binary star system, two stars that seem to have a close, symbiotic relationship. About 710 light years away, this intriguing system consists of a cool red giant star and hot, dense white dwarf star in mutual orbit around their common center of mass. The binary system's visible light is dominated by the red giant, itself a Mira-type long period variable star. But material in the cool giant star's extended envelope is pulled by gravity onto the surface of the smaller, denser white dwarf, eventually triggering a thermonuclear explosion and blasting material into space. The featured image from the Hubble Space Telescope shows the still-expanding ring of debris which spans less than a light year and originated from a blast that would have been seen in the early 1770s. The evolution of less understood energetic events producing high energy emission in the R Aquarii system has been monitored since 2000 using Chandra X-ray Observatory data.

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bcj_sf_nm@yahoo.com

Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by bcj_sf_nm@yahoo.com » Wed Jul 11, 2018 4:58 am

Has someone called this the Cowboy Nebula?

Guest

Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by Guest » Wed Jul 11, 2018 10:42 am

If it is 710 light years away doesn't that mean it takes 710 years for the light happening now to reach earth? If so, then how can you see something from 250 years ago?

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by starsurfer » Wed Jul 11, 2018 10:56 am

You can see a more natural colour version here.

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by neufer » Wed Jul 11, 2018 2:03 pm

Guest wrote:
Wed Jul 11, 2018 10:42 am

If it is 710 light years away doesn't that mean it takes 710 years for the light happening now to reach earth?
If so, then how can you see something from 250 years ago?
Something was observed in R Aquarii ~250 years ago (in 1770).

When it actually occurred is a matter of tradition/semantics:

1) Events further than 100 million light years away are generally said to have occurred in the distant past.

2) Events in our own galaxy are generally said to have occurred at the time of observation.
https://en.wikipedia.org/wiki/R_Aquarii wrote:
<<The nebula around R Aquarii is also known as Cederblad 211. It is possible that the nebula is the remnant of a nova-like outburst, which may have been observed by Japanese astronomers, in the year 930 AD.>>
Art Neuendorffer

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by neufer » Wed Jul 11, 2018 2:28 pm


bcj_sf_nm@yahoo.com wrote:
Wed Jul 11, 2018 4:58 am

Has someone called this the Cowboy Nebula?
A Cowboy heading of the rustlers at the evil chip gap.
Judy Schmidt wrote:
<<Some of the (R Aquarii) nebula was cropped off to satisfy compositional aesthetics, and because it was crossed by the evil chip gap.>>

https://en.wikipedia.org/wiki/R_Aquarii ... quarii.png
Art Neuendorffer

DL MARTIN

Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by DL MARTIN » Wed Jul 11, 2018 3:43 pm

If something was observed in the 1770s that emanated from an event 710 light years distant, then the event occurred around 1000 years ago. If astronomers are not going to cite this qualifier then one wonders as to the legitimacy of their assertion that what they do is a science. Vague terminology such as semantics/tradition culminating in a phrase such as "distant past' leaves one wondering where scientific rigor come into play.
In addition, the question of what is being missed by failing to recognize the time lapse in events occurring and observed remains a flaw in analysis.

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by MarkBour » Wed Jul 11, 2018 4:44 pm

bcj_sf_nm@yahoo.com wrote:
Wed Jul 11, 2018 4:58 am
Has someone called this the Cowboy Nebula?
Capture1.JPG
Actor William Boyd.
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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by BillBixby » Wed Jul 11, 2018 5:54 pm

Saw picture, saved same. Then I saw the Hubble and Judy combination. Roger and Judy's separate works are part of what keeps me coming back to APOD. I am in awe of all the contributors to this site. Thank you, all.

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by neufer » Wed Jul 11, 2018 5:59 pm

DL MARTIN wrote:
Wed Jul 11, 2018 3:43 pm

If something was observed in the 1770s that emanated from an event 710 light years distant, then the event occurred around 1000 years ago. If astronomers are not going to cite this qualifier then one wonders as to the legitimacy of their assertion that what they do is a science. Vague terminology such as semantics/tradition culminating in a phrase such as "distant past' leaves one wondering where scientific rigor come into play.
In addition, the question of what is being missed by failing to recognize the time lapse in events occurring and observed remains a flaw in analysis.
You should consider updating the following Wikipedia page to read:

SN -166014A (provisional name): the closest observed supernova
since Kepler's Supernova: SN -18397 (also provisional name),
which was eventually seen on earth four centuries ago.
https://en.wikipedia.org/wiki/Kepler%27s_Supernova wrote:
<<SN 1987A was a peculiar type II supernova in the Large Magellanic Cloud, a dwarf galaxy satellite of the Milky Way. It occurred approximately 168,000 ly from Earth and was the closest observed supernova since SN 1604, which was seen on earth over four centuries ago.>>
Art Neuendorffer

Just Jackson

Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by Just Jackson » Wed Jul 11, 2018 11:52 pm

Isn't this a cataclysmic variable? Eventually the white dwarf will reach it's Chandrasekhar limit and explode. 720 light years -- that's a heck of a ringside seat.

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by neufer » Thu Jul 12, 2018 3:42 am

Just Jackson wrote:
Wed Jul 11, 2018 11:52 pm

Isn't this a cataclysmic variable?
Eventually the white dwarf will reach it's Chandrasekhar limit and explode. 720 light years -- that's a heck of a ringside seat.
According to the Wikipedia article the mass of the TOTAL SYSTEM is just 1.6 - 2.5 M

So those solar winds & jets better not disperse too much more material
if the white dwarf is going to reach it's Chandrasekhar limit and explode.

Massive short lived stars are much better bets for potential nearby supernovas.
Art Neuendorffer

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by Chris Peterson » Thu Jul 12, 2018 2:57 pm

DL MARTIN wrote:
Wed Jul 11, 2018 3:43 pm
If something was observed in the 1770s that emanated from an event 710 light years distant, then the event occurred around 1000 years ago. If astronomers are not going to cite this qualifier then one wonders as to the legitimacy of their assertion that what they do is a science. Vague terminology such as semantics/tradition culminating in a phrase such as "distant past' leaves one wondering where scientific rigor come into play.
In addition, the question of what is being missed by failing to recognize the time lapse in events occurring and observed remains a flaw in analysis.
The fact that you are incapable of understanding the scientific argument does not demonstrate that it lacks rigor. It is fundamental to modern physics that the time of observation is the critical factor in most cases. That the time of observation is, in fact, equivalent to the time of occurrence in the relevant spacetime frame that usually matters.
Chris

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Re: APOD: Symbiotic R Aquarii (2018 Jul 11)

Post by starsurfer » Sat Jul 14, 2018 1:27 pm

Just Jackson wrote:
Wed Jul 11, 2018 11:52 pm
Isn't this a cataclysmic variable? Eventually the white dwarf will reach it's Chandrasekhar limit and explode. 720 light years -- that's a heck of a ringside seat.
Nah it's a symbiotic binary.