APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

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Expand view Topic review: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Laramur » Fri Jan 10, 2020 12:24 pm

I love this very creative and didactic photography of Tragoolchitr Jittasaiyapan, I congratulate you for choosing it as an apod;) I belong to an astronomy group where we make public observations, people often think that a bright star like Sirius must be the largest and as you know they are very wrong, so I want to draw a picture of these stars with their estimated size to scale and I need the data, from a serious and rigorous source, of the equivalence with the solar radius of these 25 stars (for example Sirius 1,711 R☉) . I have tried to find the information in SIMBAD but I have not known how to do it. Do you know any online page with this type of star information? Thanks a lot!

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Chris Peterson » Sun Jul 07, 2019 1:43 pm

Evenstar wrote: Sun Jul 07, 2019 6:38 am Think of all the exoplanets missed all over our galaxy because their planetary plane is perpendicular (or nearly perpendicular) to Earth.
Of course, systems that depend upon transits for detection are sensitive to geometry (although we have a large enough sample to know how many other stars also have planets, based on statistics alone). But we are starting to put into place systems that can image exoplanets directly. Those will allow us to identify planets in systems that aren't nearly edge-on to us.

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Evenstar » Sun Jul 07, 2019 6:38 am

Think of all the exoplanets missed all over our galaxy because their planetary plane is perpendicular (or nearly perpendicular) to Earth.

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by neufer » Thu Jun 27, 2019 11:58 am

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Click to play embedded YouTube video.
Ann wrote: Thu Jun 27, 2019 8:50 am
1) Betelgeuse (bolometric energy output) or Rigel (bolometric energy output).
Or: 1) Rigel and Deneb (tie): Visual light.
3) Antares (bolometric light).
5) Canopus (visual light).
Or: 5) Adhara (bolometric light).
6) Adhara (visual light).
7) Hadar.
8) Mimosa or Acrux.
9) Acrux or Mimosa.
10) Shaula.
11) Spica.
12) Achernar.
13) Gacrux.
14) Aldebaran.
15) Regulus.
16) Arcturus.
17) Capella.
18) Pollux.
19) Castor.
20) Vega.
21) Sirius.
22) Fomalhaut.
23) Altair.
24) Procyon.
25) Rigil Kentaurus.

Okay, that's it! That's my ranking of the 25 stars in the APOD according to their sometimes visual and sometimes bolometric magnitude. Sue me!

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Thu Jun 27, 2019 8:50 am

Well, okay. I ranked the 25 stars on the list according to their intrinsic luminosity, starting with the least luminous ones. This is my list so far:

1) Rigil Kentaurus

2) Procyon

3) Altair

4) Fomalhaut

5) Sirius

6) Vega

7) Castor

8) Pollux

10) Capella or Arcturus

11) Arcturus or Capella

12) Regulus

13) Aldebaran

14) Gacrux

15)

16)

17)

18)

19)

20)

21)

22) Deneb or Antares

23) Antares or Deneb

24) Rigel/Betelgeuse

25) Betelgeuse(?)


Okay. Betelgeuse, Rigel, Antares and Deneb are true supergiant stars of luminosity class Ia. None of the other stars on the list are supergiant stars. But why not try to make the list complete?

First I will have to check out the remaining stars, Canopus, Achernar, Hadar, Acrux, Spica, Mimosa, Adhara and Shaula, with the help of my software Guide. I note that with the exception of Canopus, all the remaining stars belong to spectral class B. That makes it a bit easier to compare them. It is at least moderately okay to start by just comparing their intrinsic optical luminosities (as calculated by their apparent luminosities and their Hipparcos distances) and then assume that their "bolometric correction", when you take their total energy production into account, will be at least reasonable similar.

So. According to my software Guide, the optical luminosities of the seven remaining B-typ stars are as follows: Achernar, 1004 L. Hadar (which is a triple star), 6850 L. Acrux (also a triple star), 3990 L. Spica (a double star), 1980 L. Mimosa (a mostly "single" star with a few puny companions), 1920 L. Adhara (mostly single, with a puny companion), 3220 L. Shaula (a double star), 5700 L.

So how do we make sense of these B-type stars as to how intrinsically bright they are? Bear in mind that their calculated luminosities are critically dependent on the Hipparcos measurements of their distances, and the Hipparcos margin of error is large at the distances of these faraway stars.

Anyway. According to Wikipedia, Achernar is the faintest of these seven B-type stars. All the rest are spectral classes B0, B1 or B2, but Achernar is spectral class B3 (B6 according to Wikipedia). According to Wikipedia, the luminosity of Achernar is "only" 3,150 L, and that includes ultraviolet light. All right, Achernar is number 14 on my list.

I have to confess that the other six B-type stars drove me crazy. They are all very far away, the distances to them are uncertain, and new calculations by other sources than Hipparcos seem to have assigned new distances to some of them, some of them are multiple stars with very bright companions, and the confusion of Mv (total visual light) versus Mbol (total energy output) is more than enough to make me confused as to how to list these stars.

But anyway, here goes. Spica follows after Achernar on my list. After Spica comes, maybe, Shaula. After Shaula comes, if you consider the brightness of the individual stars only, Acrux, but if you consider the total output of the multiple star system, Mimosa. The next one is the one I didn't pick for number 17, Acrux or Mimosa. I'm going to pick Hadar as number 19 on my list, and number 20 vill be Adhara.

So where do I put Canopus? The thing about Canopus is that it is very visually bright, some 13,000 L according to my software. But according to Wikipedai it's only 10,700 L. Also, because Canopus is an F-type star, it emits most of its light in the visual range of the spectrum, and its "bolometric correction" is very small. What you see is what you get from Canopus. So, if we consider bolometric luminosity, Canopus should probably be number 15 on my list, just after Achernar, but if you consider visual luminosity, Achernar is among the top 5, just after Deneb.

My goodness! Okay, here is my list, and now I'm starting from the top.

1) Betelgeuse (bolometric energy output) or Rigel (bolometric energy output).

Or: 1) Rigel and Deneb (tie): Visual light.

3) Antares (bolometric light).

5) Canopus (visual light).

Or: 5) Adhara (bolometric light).

6) Adhara (visual light).

7) Hadar.

8) Mimosa or Acrux.

9) Acrux or Mimosa.

10) Shaula.

11) Spica or Canopus (bolometric light).

12) Achernar.

13) Gacrux.

14) Aldebaran.

15) Regulus.

16) Arcturus.

17) Capella.

18) Pollux.

19) Castor.

20) Vega.

21) Sirius.

22) Fomalhaut.

23) Altair.

24) Procyon.

25) Rigil Kentaurus.


Okay, that's it! That's my ranking of the 25 stars in the APOD according to their sometimes visual and sometimes bolometric magnitude. Sue me!

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Thu Jun 27, 2019 6:38 am

BDanielMayfield wrote: Wed Jun 26, 2019 8:58 pm
Ann wrote: Wed Jun 26, 2019 7:55 pm
BDanielMayfield wrote: Wed Jun 26, 2019 2:28 pm Wow Ann, composing that (2nd previous) post took a massive amount of work. A question though, what is your ranking basis?
Well, apart from my software Guide, I rely almost entirely on Jim Kaler's Stars.

Ann
Ok, that's your source. (I just use Wikipedia, expecting it to be fairly up to date.) But what I meant was, on what basis were you ranking them. Upon rereading your comment I see it was from least intrinsically bright upwards. I was being intrinsically dull in not realizing that at first. :oops: :lol2:
Well, I was trying to answer a question from Evenstar. It was my impression that Evenstar asked how the Sun compares with 25 stars on the list. Then I got interested and decided to make a list. I wanted to show Evenstar that all the stars on the list are intrinsically brighter than the Sun. And when I ranked the 25 stars I decided to start at the bottom, because it is easiest by far to start with the least luminous ones. They are very nearby usually main sequence stars whose brightness and distance we can be sure of, and whose mass can reasonably be estimated.

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Wed Jun 26, 2019 8:58 pm

Ann wrote: Wed Jun 26, 2019 7:55 pm
BDanielMayfield wrote: Wed Jun 26, 2019 2:28 pm Wow Ann, composing that (2nd previous) post took a massive amount of work. A question though, what is your ranking basis?
Well, apart from my software Guide, I rely almost entirely on Jim Kaler's Stars.

Ann
Ok, that's your source. (I just use Wikipedia, expecting it to be fairly up to date.) But what I meant was, on what basis were you ranking them. Upon rereading your comment I see it was from least intrinsically bright upwards. I was being intrinsically dull in not realizing that at first. :oops: :lol2:

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Wed Jun 26, 2019 7:55 pm

BDanielMayfield wrote: Wed Jun 26, 2019 2:28 pm Wow Ann, composing that (2nd previous) post took a massive amount of work. A question though, what is your ranking basis?
Well, apart from my software Guide, I rely almost entirely on Jim Kaler's Stars.

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Wed Jun 26, 2019 2:28 pm

Wow Ann, composing that (2nd previous) post took a massive amount of work. A question though, what is your ranking basis?

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Wed Jun 26, 2019 9:55 am

So which of the stars on the list is intrinsically the brightest?

The prize for the brightest star in optical light of the 25 on the list should probably be shared between Rigel and Deneb. Rigel, spectral class B8 Ia, has a visual luminosity some 49,300 L. But because Rigel is a B-type star, albeit a cool B-type star, it produces quite a bit of ultraviolet light, pushing its bolometric (total) luminosity to 85,000 L.

Deneb, spectral class A2 Ia, is probably as bright as Deneb in visual light. Its visual luminosity is 49,000 L, but at the distances we are talking about (some 1,400 light-years for Deneb as measured by Hipparcos), 49,300 L is the same thing as 49,000 L, in view of the margins of error here. In optical light, Rigel and Deneb are equals. But because Deneb is considerably cooler than Rigel it doesn't produce as much ultraviolet light as the Orion luminary, and Deneb's bolometric luminosity is probably "no more" than some 54,000 L.

The brightest star on the list, when you take its bolometric (total) luminosity into account, may be Betelgeuse. Its optical light, according to Hipparcos, is some 13,000 L. But Betelgeuse is a huge and very cool star, and it produces enormous amounts of infrared light. Jim Kaler estimated that the bolometric luminosity of Betelgeuse might be 85,000 L, just like Rigel, but it might be more, up to perhaps 100,000 L or possibly even more.

I should add that Antares, while visually no contender of Deneb (some 10,000 L in optical light versus some 49,000 L for Deneb), is probably outshining Deneb in bolometric light, some 60,000 L versus perhaps 54,000 L for Deneb.

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Wed Jun 26, 2019 5:02 am

Evenstar wrote: Tue Jun 25, 2019 6:06 pm What a surprise. Let's not talk apparent. Let's pretend we are on a planet in another solar system among these "brightest" stars. Where does the sun fit in?

Any exoplanets? Or are the brightest too bright to "see"?
All the stars on the list are intrinsically brighter than our Sun.

1) The intrinsically faintest of the 25 on the list is Rigil Kentaurus, which consists of a pair of stars, Alpha Centauri A and Alpha Centauri B. Actually, Alpha Centauri B is fainter than the Sun, about 0.5 L, but Alpha Centauri A, the "solar twin", is 1.5 L. Alpha Centauri A is the same spectral class as the Sun, G2V, but it is a little bit more massive, 1.1 M. Alpha Centauri B is 0.92 M and spectral class K1V. So why does Alpha Centauri, Rigil Kentaurus, look so bright in our night skies? It is because this triple star (including ultra-faint Proxima Centauri) is the most nearby of all stars, except the Sun, of course. The distance to Alpha Centauri is only 4.4 light-years.

I think, although I'm not sure, that Alpha Centauri B has a planet.

2) So, counting backwards and beginning with the faintest ones on the list, the next one after Alpha Centauri would be Procyon (Procyon), spectral class F5IV-V and a little hotter than the Sun (but not much hotter), with a mass of 1.4 M and a luminosity of 7 L, at a distance of some 11 light-years.

3) After Procyon comes Altair (Altair), A7IV-V, with a mass of 1.7-1.8 M and a luminosity of 10.6 L, at a distance of around 17 light-years.

4) Then we have Fomalhaut, A3V, with a mass 2 M and a luminosity of 16 L, at a distance of 25 light-years. Fomalhaut has a planet.

5) Then comes Sirius, A1V, with a mass of 2.12 M and a luminosity of 26 L, at a distance of 8.6 light-years.

6) Number six is Vega, A0V, with a mass of 2.3 M and a luminosity of 36 L, at a distance of 25 light-years.

7) Number seven is Castor, A1V, with a mass of 2.4 M and a luminosity of 37 L, at a distance of 51 light-years.

8) Number eight is Pollux, K0III, the first true giant on the list. Pollux has exhausted its core hydrogen and become a red giant, albeit a pale and faint one. Its mass is probably around 1.8 M and its luminosity is 46 L. Pollux has a planet.

Now it's getting complicated. Number 9 might be Capella, which consists of two components, 93 and 64 L, spectral classes G5III and G0III, with masses of 3.0 and 2.5 M, at a distance of 43 light-years. Both components are giants. Then again, number 9 might be Arcturus, spectral class K2III, which is a single star with a luminosity of 113 L (215 L is its infrared light is included) and a mass of about 1.5 M, at a distance of 37 light-years.

11) Number eleven is probably Regulus, spectral class B7IV-V, has a luminosity of 150 L (360 L if its ultravilolet light is taken into account) and a mass of 3.4 M, at a distance of 79 light-years.

12) Number 12 is probably Aldebaran, spectral class K5III, with a luminosity of some 160 L (425 L if infrared light is included) and a mass of 1.7 M, at a distance of 67 light-years.

13) Number 13 is probably Gacrux of spectral class M4III. Its optical luminosity is about 142 L, but its optical + infrared luminosity is about 1,500 L. The mass of Gacrux is about 3 M or less, and it is located at a distance of 88 light-years.

But I'm giving up now. The rest of the stars are all really bright and far away, and many or most of them are either binaries, or multiple stars, or giants, or supergiants. It is too hard to figure out exactly what their masses are, or exactly how bright they are, when you have to consider both their optical and their ultraviolet or infrared light.

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Ann » Wed Jun 26, 2019 3:33 am

TheZuke! wrote: Tue Jun 25, 2019 3:34 pm
Ann wrote: Tue Jun 25, 2019 4:38 am ...
As a color commentator,
...
In my book, you are THE color commentator on APOD!

B^)
Thanks! :D

Ann

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Tue Jun 25, 2019 10:32 pm

Evenstar wrote: Tue Jun 25, 2019 6:06 pm Any exoplanets? Or are the brightest too bright to "see"?
We now know enough to expect there to be exoplanets in just about ALL single star systems, but among this bright star set there is only one CONFIRMED exoplanet (so far), Pollux b.

Among the multiple star systems there is the confirmed Proxima b, although it doesn't lie inside the field of view of Alpha Cen's (Rigil Kentaurus) picture.

A few other systems in this group are strongly suspected of containing a planet or planets, such as Fomalhaut, Alpha Cen B and one or two more. Usually though confirmation of an exoplanet's existence comes not from "seeing" it (by direct imaging) but by carefully noting over time subtle changes in a star's light caused by the planet's orbit.

Bruce

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Tue Jun 25, 2019 7:16 pm

zendae1 wrote: Tue Jun 25, 2019 5:54 pm Today's APOD sent me on a long mission: I wanted to see if there was one single distinguishing feature of each star. It wasn't easy, but I kinda succeeded. And some may be inaccurate; it's just what I found.
Gacrux - nearest red giant
Castor - a whopping 6 star amalgam
Shaula/Adhara - these have been discussed above
Mimosa - hottest out of the bunch
Deneb - brightest distant star
Fomalhaut - the loneliest star
Pollux - closest giant to the sun (I am assuming there is a difference between this and Gacrux)
Spica - a binary only 11 million miles apart
Antares - relatively young star nearing supernova
Aldebaran - most famous in mythology, literature, and music
Acrux - the star of Magellan
Altair - one of the few stars we have a pic of it's surface
Hadar - a binary approaching supernova
Betelgeuse - most variable magnitude
Achernar - the flattest star; it's egg-shaped
Procyon - has a dead white dwarf
Rigel - will be the brightest next to the moon when it goes supernova
Capella - it's xray emissions started xray stellar astronomy
Vega - the past, and the future's North Star
Arcturus - one of three flashing stars (all I could find)
Rigil Kentaurus - as we know, the closest star(s)
Canopus - rich in ancient culture with many names
Sirius - #1
Nice list zendea1. The best APODs do often inspire additional research.

Bruce

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Tue Jun 25, 2019 6:36 pm

Ann wrote: Tue Jun 25, 2019 4:38 am Fascinating! Has Tragoolchitr Jittasaiyapan taken all these pictures himself? They do seem to have been made in the same way.
I wondered about that as well. Not to disparage this work, but couldn't this very informative grouping have been assembled from photos that are in the public domain?

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Chris Peterson » Tue Jun 25, 2019 6:27 pm

Evenstar wrote: Tue Jun 25, 2019 6:06 pm What a surprise. Let's not talk apparent. Let's pretend we are on a planet in another solar system among these "brightest" stars. Where does the sun fit in?
The Sun has an absolute magnitude of 4.83. You could look up the absolute magnitudes of the 25 stars here for comparison. For example, Sirius has an absolute magnitude of 1.4, making it 23 times more luminous than the Sun. Rigil Kentaurus has an absolute magnitude of 4.38, so only 1.5 times more luminous than the Sun. And Rigel is over 100,000 times more luminous.

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Tue Jun 25, 2019 6:17 pm

Cousin Ricky wrote: Tue Jun 25, 2019 1:48 pm Rigil Kentaurus is a double star, and Tragoolchitr photographed them as a unit. Considered as components, Alpha Cen A is #4, but Alpha Cen A and B combined are brighter than Arcturus.
Cousin Ricky's comment made me wonder how many of these stars are multiples. I did some research, and it turns out that most of these stars' light comes from more than one star (although a primary vastly dominates in most systems). This follows from the fact that the majority of all star systems are multiples.

Extra credit question, how many of the FOURTEEN multiples hidden in this group can you name? (There are actually at least fifteen multiple star systems in today's APOD, but Fomalhaut's two companions are distantly out of frame.)

Answer (with extra multiplicity info):
Sirius, Rigil Kentaurus (aka Alpha Cen, along with distant Proxima), Rigel (system of at least 4), Procyon, Achernar, Hadar (3), Acrux (6), Antares, Spica, Mimosa, Regulus (4), Adhara, Shaula, and Castor (6).

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Evenstar » Tue Jun 25, 2019 6:06 pm

What a surprise. Let's not talk apparent. Let's pretend we are on a planet in another solar system among these "brightest" stars. Where does the sun fit in?

Any exoplanets? Or are the brightest too bright to "see"?

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Chris Peterson » Tue Jun 25, 2019 5:57 pm

Evenstar wrote: Tue Jun 25, 2019 5:49 pm How does Sol fit into the 25 brightest--I think it is way off the list?
Since we're talking apparent magnitude here, not absolute, Sol is way off the list to the upper left- over 25 magnitudes brighter than Sirius. That is, it is about 12 billion (12 x 109) times brighter.

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by zendae1 » Tue Jun 25, 2019 5:54 pm

Today's APOD sent me on a long mission: I wanted to see if there was one single distinguishing feature of each star. It wasn't easy, but I kinda succeeded. And some may be inaccurate; it's just what I found.
Gacrux - nearest red giant
Castor - a whopping 6 star amalgam
Shaula/Adhara - these have been discussed above
Mimosa - hottest out of the bunch
Deneb - brightest distant star
Fomalhaut - the loneliest star
Pollux - closest giant to the sun (I am assuming there is a difference between this and Gacrux)
Spica - a binary only 11 million miles apart
Antares - relatively young star nearing supernova
Aldebaran - most famous in mythology, literature, and music
Acrux - the star of Magellan
Altair - one of the few stars we have a pic of it's surface
Hadar - a binary approaching supernova
Betelgeuse - most variable magnitude
Achernar - the flattest star; it's egg-shaped
Procyon - has a dead white dwarf
Rigel - will be the brightest next to the moon when it goes supernova
Capella - it's xray emissions started xray stellar astronomy
Vega - the past, and the future's North Star
Arcturus - one of three flashing stars (all I could find)
Rigil Kentaurus - as we know, the closest star(s)
Canopus - rich in ancient culture with many names
Sirius - #1

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by Evenstar » Tue Jun 25, 2019 5:49 pm

How does Sol fit into the 25 brightest--I think it is way off the list?

Do any of these brightest have any exoplanets?

Thanks.

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by BDanielMayfield » Tue Jun 25, 2019 5:08 pm

An altogether most excellent APOD!

Apparently, the exposure times of the 25 different photos vary widely, since the contrast in apparent brightness isn't near as large as these actually appear to the eye. The apparent magnitudes range from Sirius' -1.46 (almost twice as bright as runner up Canopus at -0.74) down to 25th ranked Gacrux at mag +1.63. Seeing this set of star systems shown with a more realistic depiction of their differences in brightness would be an improvement on this already excellent work.

Bruce

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by neufer » Tue Jun 25, 2019 4:13 pm

Cousin Ricky wrote: Tue Jun 25, 2019 1:52 pm
I never realized Shaula was so high in the rankings! I guess I it wasn’t on my radar because it just missed the 1st magnitude cutoff.

So my next question is: how did it end up as a lambda?
At 37º declination Shaula was so low in the sky that it proved difficult to compare with other bright stars of Scorpius :?:
https://en.wikipedia.org/wiki/Lambda_Scorpii wrote:

<<Lambda Scorpii (λ Sco), formally named Shaula, is, despite being designated "λ" (Lambda), the second-brightest star system in the constellation of Scorpius. Shaula, which comes from the Arabic الشولاء al-šawlā´ meaning 'the raised [tail]', as it is found in the tail of Scorpius, the scorpion.

Lambda Scorpii is located some 570 light-years away from the Sun. Spectroscopic and interferometric observations have shown that it is actually a triple star system consisting of two B-type stars and a pre-main-sequence star. The primary star is a Beta Cephei variable star with rapid brightness changes of about a hundredth of a magnitude. The pre-main-sequence star has an orbital period of 6 days and the B companion has a period of 1053 days. The three stars lie in the same orbital plane, strongly suggesting that they were formed at the same time. The masses of the primary, pre-main-sequence star and the B companion are 14.5, 2.0 and 10.6 solar masses, respectively. The age of the system is estimated to be in the range 10–13 million years.>>

Re: APOD: 25 Brightest Stars in the Night Sky (2019 Jun 25)

by TheZuke! » Tue Jun 25, 2019 3:34 pm

Ann wrote: Tue Jun 25, 2019 4:38 am ...
As a color commentator,
...
In my book, you are THE color commentator on APOD!

B^)

"something that touches the sky"

by neufer » Tue Jun 25, 2019 2:57 pm

starsurfer wrote: Tue Jun 25, 2019 1:57 pm
Does anyone know what Zubenelgenubi means? :D
https://en.wikipedia.org/wiki/Alpha_Librae wrote:


<<Zubenelgenubi, also rendered Zuben Elgenubi, derives from the Arabic ّالزُبَانَى الجَنُوبِي al-zubānā al-janūbiyy "the southern claw", which was coined before Libra was recognized as a constellation distinct from Scorpius. (Zubeneschamali, derived from the Arabic ّالزُبَانَى الشَمَالِي meaning "The Northern Claw".) The alternative name Kiffa Australis (Elkhiffa Australis) is a partial Latin translation of the Arabic al-kiffah al-janubiyyah الكفة الجنوبية "southern pan [of the scales]". Another name used in older astronomy texts, equivalent to "southern pan", was Lanx Australis.

Zubin (Persian: زوبین‎) is a Persian male given name (e.g., Zubin Mehta), which means short spear in Persian, literally meaning "something that touches the sky". The name originated in Iran, Iran. In Persian mythology, Zubin (also called: Zupin, Zhubin, Zhupin) was one of the warriors of Iran's army, famous for his courage. "Zubin" was also a weapon as well "a short spear that would be thrown to kill the enemy.>>

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