A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Astronomy Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Who's bright idea was it to call our galactic core's black hole "Sagittarius A Star"



 
 
Thread Tools Display Modes
  #1  
Old June 17th 13, 09:21 AM posted to sci.astro
Dave Rove
external usenet poster
 
Posts: 1
Default Who's bright idea was it to call our galactic core's black hole "Sagittarius A Star"

Assuming that's how SGR A* is pronounced. It's as confusing in a
conversation as talking about your dog that you've named "My Ass".
  #2  
Old June 17th 13, 10:08 AM posted to sci.astro
Mike Dworetsky
external usenet poster
 
Posts: 715
Default Who's bright idea was it to call our galactic core's black hole "Sagittarius A Star"

Dave Rove wrote:
Assuming that's how SGR A* is pronounced. It's as confusing in a
conversation as talking about your dog that you've named "My Ass".


It's a very odd complaint. I can't see your point. Is your dog really
named that? I can see why it might be confusing, as in "I want to have fun
with (name of dog) and scratch its fur". The only persons you are ever
likely to discuss it with verbally are astronomers, and they will all know
what you mean.

The name originated, if memory serves, with radio and infrared astronomers
who needed to distinguish the galactic central bright object called Sgr A (=
brightest radio source in Sagittarius) and the western patch called Sgr A
West from a later discovery of an unresolved radio and infrared bright spot
within Sgr A, which was called Sgr A*. Not sure of the exact date without a
literature search, but probably in the 1980s.

--
Mike Dworetsky

(Remove pants sp*mbl*ck to reply)

  #3  
Old June 17th 13, 08:22 PM posted to sci.astro
Steve Willner
external usenet poster
 
Posts: 1,172
Default Who's bright idea was it to call our galactic core's black hole "Sagittarius A Star"

In article ,
"Mike Dworetsky" writes:
The name originated, if memory serves, with radio and infrared astronomers


All radio. In the very early days, radio sources were named
according to the constellation and then in order of brightness.
Sgr A was thus the brightest radio source in Sagittarius.

When better maps came along about 1980, new names were needed. Sgr A
was broken into "Sgr A East," a nonthermal source, and "Sgr A West,"
which turns out to be a collection of H II regions near the Galactic
center.

A different scheme was used for Sgr B: we have Sgr B1 and Sgr B2.
Astronomical nomenclature doesn't always follow set rules, though
things are better now than a generation ago.

who needed to distinguish the galactic central bright object called Sgr A (=
brightest radio source in Sagittarius) and the western patch called Sgr A
West from a later discovery of an unresolved radio and infrared bright spot
within Sgr A, which was called Sgr A*.


The point source was discovered in 1974 (Balick & Brown, ApJ 194,
265). The discovery was based on limited interferometry data. Full
synthesis data came along about five years later. Bob Brown (1982
ApJ 162, 110) made up the name "Sgr A*" for the point source, and the
name stuck. I don't think it's so bad.

--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
  #4  
Old June 19th 13, 11:19 AM posted to sci.astro
Martin Brown
external usenet poster
 
Posts: 1,707
Default Who's bright idea was it to call our galactic core's black hole"Sagittarius A Star"

On 17/06/2013 09:21, Dave Rove wrote:

Assuming that's how SGR A* is pronounced. It's as confusing in a
conversation as talking about your dog that you've named "My Ass".


Astronomers are a bit lazy and it might well be shortened to Sag A star.

They are the names given to objects in the first imprecise radio surveys
of the brightest objects giving them names of the form:

constellation Roman letter

A brightest, B second brightest etc. They tend to be very well studied
objects and the original names have largely stuck with them!

By analogy with bright stars which were Greek letterconstellation

Some of these objects are bright and extensively studied with modern
telescopes detailed so that the original name has stuck. Sgr A and it's
various components is one such as are SNR Cas A and radio galaxy Cyg A.

Later radio catalogues used observatory tagnumber 3C461 and 3C405
respectively for the latter two in the third Cambridge catalogue. Or at
Parkes PKS 1548+05 (that's RA & Dec 1950.0 based)

Arguably it is more informative for humans to have constellation names
than some date of discovery or RA&Dec based long numeric string.

BTW: Why have you given your dog such a silly name?

--
Regards,
Martin Brown
  #5  
Old June 21st 13, 05:10 AM posted to sci.astro
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,692
Default Who's bright idea was it to call our galactic core's black hole"Sagittarius A Star"

On 17/06/2013 4:21 AM, Dave Rove wrote:
Assuming that's how SGR A* is pronounced. It's as confusing in a
conversation as talking about your dog that you've named "My Ass".


Well, I guess you could also call it SGR A asterisk, if you want. "Star"
just seems simpler to pronounce that "asterisk".

Yousuf Khan
  #6  
Old June 21st 13, 05:16 AM posted to sci.astro
Yousuf Khan[_2_]
external usenet poster
 
Posts: 1,692
Default Who's bright idea was it to call our galactic core's black hole"Sagittarius A Star"

On 17/06/2013 5:08 AM, Mike Dworetsky wrote:
Dave Rove wrote:
Assuming that's how SGR A* is pronounced. It's as confusing in a
conversation as talking about your dog that you've named "My Ass".


It's a very odd complaint. I can't see your point.


I think his complaint is about the word "star" in the name. Since we're
talking astronomy here, the word "star" has a very specific meaning in
this field (i.e. a big ball of plasma undergoing nuclear fusion), so why
would they name this region of space with the word "star" in it, when
it's clearly something way more than any star. When you say the name out
loud, "Sagittarius A Star", it sounds like you're talking about a star,
like "Alpha Centauri B star", or "Sirius A star".

Yousuf Khan
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
just THREE YEARS AFTER my "CREWLESS Space Shuttle" article, theNSF """experts""" discover the idea of an unmanned Shuttle to fill the2010-2016 cargo-to-ISS (six+ years) GAP gaetanomarano Policy 3 September 15th 08 04:47 PM
Black hole form in finite "external" time [email protected] Astronomy Misc 4 February 16th 07 04:48 PM
"Is There a Force of Gravity?" (my deathblows; also anbringup of the black hole) Autymn D. C. Astronomy Misc 0 December 2nd 06 08:01 AM
Scientists Find Black Hole's "Point of No Return" (Forwarded) Andrew Yee Astronomy Misc 0 January 9th 06 05:48 PM
Scientists Find Black Hole's "Point of No Return" (Forwarded) Andrew Yee News 0 January 9th 06 05:19 PM


All times are GMT +1. The time now is 08:42 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.