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Antares is a class M class M stars are red dwarfs, Anares is a Giant I'm not sure of its classification but it would be "B" or "A" I would think.(Zach Kessin
Stellar class is based not on size, but on temperature, and Class M includes both supergiants like Antares and red dwarf stars. —Preceding
unsigned comment added by
72.49.66.68 (
talk)
20:57, 7 July 2009 (UTC)reply
Diameter
Antares is a class M supergiant star, with a diameter of approximately 9.24 × 10^8 km, or slightly more than the distance from the Sun to Mars,
You are correct, Mars is "only" 1.52 AU (give or take) = 2.3 X10^8 km, I believe it should say Jupiter (at 7.8 X10^8km)--
Kalsermar16:41, 10 June 2006 (UTC)reply
But the passage mentions that the diameter is 9 x 10^8 km (~6 AU). An Antares placed where the Sun is would not stretch out as far as Jupieter's orbit, but only about 3 AU. Well beyond the orbit of Mars at ~1.5 AU, but not as far as Jupiter, at ~5.2 AU. 3 AU would be somewhere in the asteroid belt.
Richard B20:25, 10 June 2006 (UTC)reply
Now the article states Antares diameter is 1.33 × 109 km which means in place of our sun it would extend out half that or to 6.7 x 108 km. Could someone with a source provide a fact check and cite it?
WilliamKF01:25, 11 August 2006 (UTC)reply
According to
APOD (I know, not the best source for scientific data but it is what I found doing a quick search) Antares is about 700 times the solar diameter. That would make it roughly 9.8 x 108 km.--
Kalsermar16:49, 11 August 2006 (UTC)reply
Antares has a measured parallax of 5.4 mas (milliarcseconds), so the distance is 1000/5.4 = 185 parsec. Furthermore, the CHARM2 database (CHARM2: an updated Catalog of High Angular Resolution Measurements. Richichi A., Percheron I., Khristoforova M. <Astron. Astrophys. 431, 773 (2005)>) lists a measured angular disk diameter of 45 mas. Thus the diameter is 45*185/1000 =8.3 AU (astronomical units; note that one arcsec at one parsec is one AU). 8.3 AU correspond to 1780 solar radii, so the radius of the star would be 1780/2 = 890 solar radii. Of course it could easily be 200 solar radii more or less, given the observational errors.
The image has the radius of Antares at 300 million kilometers, and the sun's radius at 0.7 million kilometers, so the radius of Antares is about 430 solar radii. This does not agree with the value of 700 solar radii in the details section.
Kwierschem (
talk)
19:54, 22 April 2009 (UTC)reply
Astronomers do not measure the radius of stars directly. However, for some stars (such as Antares), the angular diameter can be measured. This, combined with the parallax measurement (distance), will determine the size of the star. Using the parallax measurement of the Hipparchus catalogue, and an angular diameter cited in the main article, I have calculated the radius of Antares in solar units to be about 800 solar radii. The exact result is 822 with an uncertainty of 80, so there is no point in including more than one significant figure (unless the uncertainty is indicated). If someone can find a better value somewhere, by all means let's use it. But citing a web page that does not give any sources is not acceptable in my opinion, so I am undoing the changes made by Thangalin in this regard.
Kwierschem (
talk)
22:55, 17 July 2009 (UTC)reply
Size in Pixels
If it were to be printed next to a picture of the sun, the sun would be just a pixel while antares would be 10 centimetres (3.9 in) in diameter.
A
pixel isn't a fixed unit of measurement (right?). Does the comparison of 1 pixel to 10 centimetres make sense?
External Link Removed
I thought my external link to
http://www.rense.com/general72/size.htmThe Size of our World on rense.com was a good one. It is a powerful visual comparison of the size of Antares to earth, sun, and other stars. Does everyone agree with Kalsermar that it should be removed?
Bytemiser03:38, 4 July 2006 (UTC)Bytemiserreply
I added a few more references, and cleaned up the subheadings.
Disk of Antares imaged
It is notable that Antares is one of the few stars whose disk has been photographed (along with the sun, of course, and Betelgeuse and I think Myra). I'm not sure how to work that into the article, but it might be worth a mention.--
Todd08:58, 30 May 2007 (UTC)reply
Location
I tried to figure out some way to actually translate the location into something more meaningful to the average person. I have failed in this. Knowing the RA doesn't help me figure out if this star is closer to galactic center, further out, or radial from our location. Perhaps this really needs to be a discussion on the page that discusses RA, but a reference on this page -- or even a graphic showing a "top down" view of our galaxy with both Sol and Antares located, would be nice. Anyone? —Preceding
unsigned comment added by
Jplflyer (
talk •
contribs)
20:17, 5 November 2008 (UTC)reply
We are looking toward galactic center, from Earth, when we look in the direction of the constellation Sagittarius, which is adjacent to Scorpio, including Antares. Hence, Antares is closer to galactic center than we are, though not directly between us and it. If I could a.) document this and b.) figure out how to phrase it well, I would work it in to the article. For now, I am putting the info here, if anyone cares to verify this with a source and work it in.
72.49.66.68 (
talk)
08:18, 7 July 2009 (UTC)reply
Most-isolated first magnitude star
I did a quick Google search on this fact and didn't find anything other than references back to Wikipedia. If it's true there needs to be some explanation. Did Fomalhaut and Achernar dim below first magnitude? Did their proper motion or that of Antares or Alpha Centauri cause the change?
Rsduhamel (
talk)
07:59, 14 November 2008 (UTC)reply
Inconsistency in article
I came to the talk page to point out that the text (Antares's radius is approximately 800 times that of the Sun) is inconsistent with the image (showing the Sun's radius as 0.7 and Antares's as 300, both in million km). I see this was pointed out last year in the
#Diameter thread above. I can't follow all the technical stuff in that thread, but as a layperson I can tell you that the article in its current state cannot be right and is confusing besides. If the measurement is imprecise, then we should report the imprecision, instead of acting as if two inconsistent values are both well-established facts that need no qualification.
JamesMLanetc06:29, 23 February 2010 (UTC)reply
I couldn't add this to the article because it is the result of my own observation, but when I observed Antares B during a lunar occultation in West Virginia on 25 January 1968, during which I was able to observe the companion star by itself for many seconds, it appeared a rich blue color. This surprised me because I had hitherto observed the companion only as a green "corner" of the bright star Antares when seen through a telescope. I observed no green in the companion when viewed by itself; it was more the color of natural ultramarine.
Embram (
talk)
23:05, 21 November 2012 (UTC)reply
Labeling of size comparison drawing
I notice in this drawing Antares is labeled as a giant star, which contradicts the article. Additionally , Arcturus is labeled as an 'orange star' rather than referring to its giant status
Mr Morden76 (
talk)
18:42, 23 April 2013 (UTC)reply
Brightness of Secondary compared to Antares
The figure 1/370 is not consistent with 170 solar brightnesses for the secondary compared with 10,000 for Antares which is a factor of 59 and consistent with the approximate 4.5 magnitude difference. — Preceding
unsigned comment added by
58.167.134.188 (
talk)
09:01, 12 June 2013 (UTC)reply
The sixteenth brightest star?
At present the article has "...and
the sixteenth brightest star in the nighttime sky. It is sometimes listed as 15th brightest, if the two brighter components of the
Capella quadruple star system are counted as one star."
By definition, irregular variables do not have an identifiable period. It is also described as "slow", so I think we can rule out milliseconds, which are extremely unlikely for a red supergiant in any case. In practice the period varies, over quite a small amplitude, on a period of hundreds of days. Mathematical analysis of the variations over a sufficiently long period can resolve most irregular variables into a number of overlapping (semi-) regular periods. In the case of Antares, two dominant periods are resolved at about 300 and 1700 days. Many references, but try DOI 10.1088/0004-637X/725/1/1170 for a starting point.
Lithopsian (
talk)
11:02, 16 October 2013 (UTC)reply
Last occultation by Venus was when?
According to the article section Position on the ecliptic, "The last occultation of Antares by Venus took place on September 17, 525 BC". Generally, the use of "BC" dating implies a calendar reference such as that used primarily by historians, referring to the proleptic Julian calendar. So, does 525 BC mean year -524, or was an editor unmindful and meant -525? Also, what then of September 17? The Julian calendar officially took effect in Rome on January 1, 45 BC. But for at least 100 years, the application of leap years was not in fact done every four years, but instead was subject to the political winds and whims of the Roman Senate who had to vote on when to have one. By calendar definition, the vernal equinox was supposed to occur on March 25, 45 BC, but we know from church history that it occurred again on March 21, AD 325 (the year of the
First Council of Nicea), because from that point on Easter was calculated based on that dating. Count the supposed leap years; it doesn't work. In 370 years, the Julian calendar should have seen the equinox drift by a little less than three days, not four. I'm sure historians leave dates across those 370 years as they occurred historically. "Proleptic" does not truly apply to the Julian calendar until one gets earlier than 45 BC. So the historical date for the occultation is perhaps September 18th. But that's not what astronomers do with that calendar. They apply a fully regular four-year pattern of leap years to all times before 1582.
I'm not arguing that astronomers are doing something wrong or unreasonable, only that it's not precisely historic. I am assuming that the occultation date has been confirmed through modern calculation that identifies the timing through a count of days (perhaps using the Julian day?), which would then be applied to the calendar as described in the "Astronomical year numbering" article. To avoid all such questions, I would recommend that the date be clearly given according to astronomical calendarization, with negative year number, a parenthesized "BC" equivalent, and a wikilink to the year numbering article to explain. I'd do it myself if I felt confident of what date is really intended, but unfortunately there is also no source given for the Venus occultations, so I couldn't check it, and came up empty looking.
Evensteven (
talk)
10:20, 19 March 2014 (UTC)reply
External links modified
Hello fellow Wikipedians,
I have just added archive links to one external link on
Antares. Please take a moment to review
my edit. If necessary, add {{
cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{
nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:
I check pages listed in
Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for
orphaned references in wikilinked articles. I have found content for some of
Antares's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.
Reference named "percy":
From
AH Scorpii: Percy, John R.; Sato, Hiromitsu (2009). "Long Secondary Periods in Pulsating Red Supergiant Stars". Journal of the Royal Astronomical Society of Canada. 103: 11.
Bibcode:
2009JRASC.103...11P.
From
RW Cephei: Percy, John R.; Kolin, David L. (2000). "Studies of Yellow Semiregular(SRd) Variables". The Journal of the American Association of Variable Star Observers. 28: 1.
Bibcode:
2000JAVSO..28....1P.
I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not.
AnomieBOT⚡16:12, 18 October 2017 (UTC)reply
Antares's new size
Should the 680 R☉ stay, or should it be accompanied by the 883 R☉? I think the second option is the best so that everyone's opinion counts. After all, many estimates made after ~2014 give Antares a radius of more than 800 R☉. Remember the footnote given on the note on
List of largest stars? Please leave another source that says 653 - 1,246 R☉ if you can find one. Thank you. --Joey P. - THE OFFICIAL(
Visit/
Talk/
Contribs)23:47, 19 October 2017 (UTC)reply
Oh please. This edit was rightfully reverted.
[1] Saying: "Should the 680 R☉ stay, or should it be accompanied by the 883 R☉? I think the second option is the best so that everyone's opinion counts." is so far from the point. Considering your own history of
edit warring on the
List of largest stars page and your involvement with this
WP:SYNTHESIS edit here.
[2] Even that footnote says (which you added): "approximately 800, derived from the 1990 lunar occultation measurement of apparent diameter of 43.1 milliarcsec (up to ±1 milliarcsec error) (
http://adsabs.harvard.edu/abs/1990A&A...230..355R page 361) together with 1997 parallax of 5.40 [1.68] milliarcsec (
SIMBAD citing
Hipparcos). The parallax gives a derived distance from 460 to 877 light years. This in turn yields an actual diameter from 653 to 1,246 solar radius. An average of 800 is used here." [Bizarrely, you now want a source for "653 to 1,246 solar radius", but that was your own
WP:SYNTHESIS from this same footnote!]
Worst, this is also contradicted by the
Antares article says: " The diameter of the limb-darkened disk was measured as 37.38″±0.06″ in 2009 and 37.31″±0.09″ in 2010."
The
Antares article also rightly now says: "Like most cool supergiants, Antares size has much uncertainty due to the tenuous and translucent nature of the extended outer regions of the star. Defining an effective temperature is difficult due to spectral lines being generated at different depths within the atmosphere, and linear measurements produce different results depending on the wavelength observed. In addition, Antares appears to pulsate, varying its radius by 165 R☉ or 19%"
Another statement on this attached 2017 article confirms: "Above the photosphere of a red supergiant, the molecular outer atmosphere extends up to about two stellar radii. Furthermore, the hot chromosphere (5,000–8,000 kelvin) and cool gas (less than 3,500 kelvin) of a red supergiant coexist at about three stellar radii."
[3]
The star isn't even fixed in size. So how big is Antares really?
Saying "Are you even blind?" avoids
WP:GF. None of the above are even relevant, and the first one you added yourself. Self-referencing is not good referencing. Please consider changes you add and stop expecting everyone to clean up your mess.
Arianewiki1 (
talk)
22:37, 20 October 2017 (UTC)reply
Sorry. You are not even listening, and this latest revert
[4] is deliberately avoiding the
WP:BRD,
WP:Consensus and is now
WP:TE. Two editors disagree with you, have given you suitable edit warnings, and yet you persist with disruptive editing. We have to move on.
Arianewiki1 (
talk)
03:59, 21 October 2017 (UTC)reply
Not sure anyone wants to touch this. Should it be mentioned? Maybe, possibly, but I suspect there are few editors that want it to be mentioned explicitly. At least not in the lead where I suspected you'd want to see it. Certain information has to remain implicit or an article becomes unreadable. An obvious example is that Antares is described in the opening sentence as a star, without any explanation of what a star might be.
Star is not even linked (although some articles about specific types of star are) and it is understood that a typical reader will know what a star is. And what "naked eye" means, also "night sky", "mass", all terms in the lead which don't occur in everyday conversations between most people, but are in the lead of this article without explanation or even links (incidentally, all three terms have their own Wikipedia article). So should it be explained that Antares is in the Milky Way, despite it being quite exceptional that any star you've heard of is not in the Milky Way? Despite the fact that there are very few articles in the whole of Wikipedia about individual stars not in the Milky Way (all explicitly described because it is such an unusual thing)? Well maybe it could be made more obvious, but I'm not keen to do it.
Lithopsian (
talk)
15:10, 10 December 2017 (UTC)reply
A Commons file used on this page has been nominated for deletion
The following Wikimedia Commons file used on this page has been nominated for deletion:
After this recent edit here
[5] and the advisement here
[6], why did you change the text from '5.0 magnitude' to 'magnitude 5.0'? IAU nomenclature is clear on this saying: "it should be written after the number."?
Arianewiki1 (
talk)
03:26, 6 June 2019 (UTC)reply
Yes, the IAU does say that. And nobody does it. Hence I don't do it, in Wikipedia, and neither should you. We're not here to change the world, or right great wrongs.
Lithopsian (
talk)
16:17, 6 June 2019 (UTC)reply
Seriously. So do you have any consensus for this? Even a cite? Your statement (an opinion not fact) above sets precedent and crosses over in failing
NPOV and editorial bias. So justification for your reverted this usage, only because you say so?
Virtually no one would agree with you on this, and the majority of books I have in my possession do not use such a convention. Magnitude is a dimensionless unit of measure, so the number precedes the unit. If we did agree with this, then we should write, 'seconds 5.8' or 'joules 5.8' or 'fahrenheit 6.0'?
Arianewiki1 (
talk)
00:11, 7 June 2019 (UTC)reply
I'm not an astronomer, but I hang around with a number of them online (and rarely IRL), mostly planetary and small bodies but stellar and astrophysics at times. I can't offhand remember seeing "5.0 magnitude" form in common communications or publications, though I am sure it's happened once or twice. "magnitude 5.0" or "5th magnitude" are usual and uncommon respectively. If it's commonly used in textbooks or publications I don't read, we can get cites up. But I almost always see "magnitude 5.0" format. I can do a tool search on something like a decade's minor planet emails if we need to.
Georgewilliamherbert (
talk)
06:01, 7 June 2019 (UTC)reply
Surely, even if one version is used, and even if versions of the format were to be adopted, the statement by
Lithopsian exceeds even basic reasoning. Usage is plainly cited and the logic of why it is adopted is shown. The IAU source appears here.
[7] and the cite is this: "IAU Style Manual" by G.A. Wilkins, Comm. 5, in IAU Transactions XXB (1989).
Arianewiki1 (
talk)
08:51, 7 June 2019 (UTC)reply
I don't think "logic" is that relevant, here. The English language has conventions, and it is sometimes inconsistent, not following logic. So I don't think the cited example of "5.8 seconds" instead of "seconds 5.8" necessarily applies. As an example of usage in another context, one normally says "magnitude 7" earthquake, not "7 magnitude" earthquake.
Attic Salt (
talk)
13:03, 7 June 2019 (UTC)reply
We are not beholden to the IAU standard; the decision on how to format this information (or whether to do it consistently one way at all) is editorial. Invoking WP:NPOV is a non sequitur. But that doesn't necessarily mean we shouldn't follow the IAU standard. Since this is a discussion about a style choice too specialist for the
WP:MOS, I suggest a good location for centralized discussion would be
WT:WikiProject Astronomy.
VQuakr (
talk)
19:13, 7 June 2019 (UTC)reply
No, they don't. I see an example of "6.5-magnitude" star, but that is with a dash to form a compound adjective. Otherwise, the examples cited by Cas Liber use "magnitude x". Thank you.
Attic Salt (
talk)
12:53, 8 June 2019 (UTC)reply
No, it isn't. Don't expect others to follow your arbitrary evidentiary standards just because you say so. This is an editorial decision.
VQuakr (
talk)
02:28, 8 June 2019 (UTC)reply
VQuarkr just go away, that is unless you can add something contructive or even relevant. Saying "Don't expect others to follow your arbitrary evidentiary standards..." is an insulting invective slur just to get a reaction to further use against me. If you bothered to read this
[8] (also said in the ANI) this is properly/formally explained. There is no imposition (nor any kind of pecieved insult here). I informed
Lithopsian nicely here. They ignored it. I again informed them there was an issue, and they responded with "Yes, the IAU does say that. And nobody does it. Hence I don't do it, in Wikipedia, and neither should you." Lithopsian is reverting edit based on an uninformed position ignoring facts for the sake of
OWN - the reverse of your false accusation. It is foolishness to suggest otherwise. Wanna test it via ANI? Speak truth please, not this irrelevant invective.
Arianewiki1 (
talk)
03:57, 8 June 2019 (UTC)reply
"Logic" here is necessary. Numbers are followed by units. As magnitude is a dimensionless unit, it follows this is how it is expressed. (A magnitude of an earthquake is actually expressed as 7.0 ML or 7.0ML, etc. There are many other earthquake magnitude scales. An ordinary (non-italic, non-bold) capital "M" without subscript is often used to refer to magnitude generically, where an exact value or the specific scale used is not important.) Stellar magnitudes follows scientific precepts based on defined restraints not airy-fairy popular contexts.
Arianewiki1 (
talk)
00:21, 8 June 2019 (UTC)reply
If you think English should follow logic, then that is your challenge. But you are badly misstating conventions for earthquake magnitudes; see
[9]. Thank you.
Attic Salt (
talk)
12:53, 8 June 2019 (UTC)reply
Read this on
Seismic magnitude scales makes this assertion rather glib. If you justify some viewpoint using the USGS, then the this supports what I've said
[10]. Science has conventions for a reason, they should be accepted or acknowledge. Someone just uses the formal usage, but their edit is overturned on opinion?
Arianewiki1 (
talk)
02:54, 9 June 2019 (UTC)reply
Um, how does any of that "support" what you've said? The sources cited either don't mention anything relevant or they use "ML 7.0", certainly not "7.0 ML".
Attic Salt (
talk)
13:02, 9 June 2019 (UTC)reply
You must of spent a long time searching for a case where the magnitude symbol appears after the numerical value (albeit in a table of values, not in sentences).
Attic Salt (
talk)
23:02, 11 June 2019 (UTC)reply
Defect!!! DEMON Antares SHOULD NOT be a link to the Star =
For the first time in over a decade I will need to go offsite to get better top level info. I want to know about the original myth on Antares. The star was named after a Greek of Roman god or goddess, I'll bet a magnum of good sparkling. I am dumbfounded and when I have time...
Bodysurfinyon (
talk)
15:32, 4 March 2021 (UTC)reply