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New Mira star discovered !

Amar A. Sharma's picture
Amar A. Sharma
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Joined: 2012-06-23

Hello folks,

This news comes in a little late, however hopefully still in time to make some follow-up measurements.

On the night of 19th and 21st June, 2012, I was attempting to image Pluto. While I compare it with DSS image to locate Pluto, I was able to make my first (accidental) celestial discovery (first amateur discovery from India in all likelihood, and no doubt Her first CCD discovery, which has also been the quickest - at just the 21st day of usage since its purchase 6 months ago). I thought its a bright nova due to inexperience in the field of variable stars. I have been a very active visual DSO observer and visual comet chaser for past few years.

Placed just 1 arc minute away from Pluto, I was astonished to see such a bright new "Nova" which I visually estimated at ~11.5 mag. I did also check with AAVSO chart plotter but didnt see anything at the source position. I contacted a virtual friend of mine, the legendary Dr. Alan Hale (of comet Hale Bopp fame) and he was able to quickly make a visual estimate at 13.5 mag on 23rd night. I shot an email to CBAT on 23rd June, awaiting them to put it up on their TOCP page as a new Nova candidate. However after an aggreviating wait of few days I got to see something by them; it turns out to be a "previously unreported Mira variable star". The reason why it appears bright in my image is it was taken unfiltered, as it was a routine imaging session. The background source is ~17th magnitude IRAS 18322-1921. The coordinates of this object are - RA 18* 35' 10" / DEC -19* 19' 31".

https://picasaweb.google.com/100263423283309558687/FirstDiscoveryOfACele...

Coincidentally the bright new Nova was discovered just 10 degrees away from my object on 26th of June!

I sincerely hope the variable star experts here can make follow up measurements of this source, which still should be quite bright. I havent taken an image after 23rd June, since this part of south India is notorious for being clouded most year round, pre and post monsoons.

Note: Do excuse me. Being a newbie to this specific field (and active in other areas of amateur astronomy), I am not sure should I be calling my accidental discovery as a Mira "type" star discovery, or new Mira star discovery itself.

Is any new discovery classified as a Mira star, or a Mira type based on its progenitor. Thanks for clarifying.

Thanking all,

Amar A. Sharma
Nikaya Observatory
off Bangalore, India
+12* 36' / 77E 43'

Your new mira
Sebastian Otero's picture
Sebastian Otero
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Joined: 2010-09-19

Hi, Amar,

Your star has been entered in VSX woth you as the discoverer:

http://www.aavso.org/vsx/index.php?view=detail.top&oid=285284

You can see the ASAS-3 light curve here:

http://www.astrouw.edu.pl/cgi-asas/asas_variable/183510-1919.5,asas3,270,3110.0000,440,270,0

Only the brighter peaks of each cycle are recorded due to the ASAS magnitude limit.

The term "progenitor" is used to identify the stars/systems that underwent an outburst. Mira stars are pulsating red giants, an this is what you found: a previously unidentified mira star.

Cheers,
Sebastian

Dear Sebastian, Many thanks
Amar A. Sharma's picture
Amar A. Sharma
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Joined: 2012-06-23

Dear Sebastian, Many thanks for letting us know its been entered in the VSX database. I see somebody was kind enough to do that.

Curious...approximately how long does it take for a new (Mira) variable to be designated. Elizabeth mentioned it will eventually be named as "Vxxxx SGR". Am keen to learn of it.

Is there any way to find out if someone in AAVSO has been following the new/unidentified star or any work being done on it? This accidental discovery holds sentiments, hence...

Thanks, Amar A. Sharma
Nikaya Observatory
Bangalore, India
+12* 36' / 77E 43'
www.picasaweb.google.com/nikayaobservatory

New Mira In SGR
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BRJ
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Joined: 2010-07-24

Hello, Amar. Perhaps a bit disappointingly for you, the process of "officially" naming a new, but rather unremarkable variable, is a very slow road today. This is particularly so in light of the fact that thousands of new variables of all sorts are being identified through the various sky surveys currently in progress.

I'm afraid that in the case of your newly discovered Mira star any official name is unlikely to be assigned for perhaps some years, given the current backlog of variable stars awaiting naming.

J.Bortle  (BRJ)

  

Curious...approximately how
FRF's picture
FRF
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Joined: 2010-08-09

Curious...approximately how long does it take for a new (Mira) variable to be designated. Elizabeth mentioned it will eventually be named as "Vxxxx SGR". Am keen to learn of it.

I'm afraid it will probably take years. If you are lucky it will be announced in one of the next "Name lists" regularly issued by the GCVS team.

http://www.sai.msu.su/gcvs/gcvs/nl80/nl80_part_2/IBVS%206008%20%2821%20D...

Hopefully your variably will be included in the Part III. of the 80th Name List of Variable Stars.

"Is there any way to find out if someone in AAVSO has been following the new/unidentified star or any work being done on it?"

1) You can use the Light Curve Generator to see whether there is any observation in the AID. Just type the VSX name of your mira star: http://www.aavso.org/lcg

2) You can subscribe to the LPV Circular and see a weekly report of all mira and SR variables: http://www.aavso.org/lpv-circular-launched

3) You can configure your MyNewsFlash in a way to report all observations of your variable: http://www.aavso.org/apps/email/#mynewsflash

But this works only in the case someone observes your variable. In order to get there you need to convince some observers that your variable deserves their attention among the thousends of other mira variables...

Clear skies,

Robert Fidrich (FRF)

There is no AUID assigned to
FRF's picture
FRF
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Joined: 2010-08-09

There is no AUID assigned to your mira, this means no observations can be/have been reported yet.

The good news is that there some comp stars in the field of IRAS 18322-1921, belonging to MAXI J1836-194, a HMXB: star (no observations either).

Naming a mira
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Sebastian Otero
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Joined: 2010-09-19

Hi, Amar,

I understand your feelings but as the other colleagues told you, a run-of-the-mill (miras are the most common type of variable star) variable is probably not going to receive much attention, specially regarding "official" naming.
Also, the fact that it has been included in VSX doesn't mean it will be taken by the GCVS people to give them a name. They usually name stars that appear in formal publications (journals like IBVS, JAAVSO, OEJV, A&A, MNRAS, etc).
So currently your star can be found in VSX and VizieR (since VSX is in VizieR). People that use these resources will find it. But receiving a Vxxxx Sgr name is another thing.

About submitting observations, since the star is in a field that is being observed these days and Robert said there were some comp stars for it, I assigned it an AUID (AAVSO Unique IDentifier) so if someone observes it, observations can be added to the AAVSO International Database (AID)

Cheers,
Sebastian

AUID assigned
Sebastian Otero's picture
Sebastian Otero
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I was about to do it but someone else had already done it so observations can be submitted now.

Cheers.

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