Affiliation
Nucleo de Estudo e Observacao Astronomica - Jose Brazilicio de Souza (Florianopolis, Brazil) (NEOA-JBS)
Sun, 08/08/2021 - 22:22

Dear friends,

RS Ophiuchi seems to be in outburst.

In August 8, 2021, at 21:55 UT I estimated it in magnitude 5.0.

An image was taken and it is at website:

http://www.geocities.ws/costeira1/img/20210808_2159ut.jpg

with regards,

AAX

Affiliation
Nucleo de Estudo e Observacao Astronomica - Jose Brazilicio de Souza (Florianopolis, Brazil) (NEOA-JBS)
Let me share my feelings:

Let me share my feelings:

After some photos in the Barnard's Star field and observing another variable stars, I think: "ok, it,s time to look to RS Oph before a high altitude", because my refractor is in a AZ3 mounting. By the finderscope it was possible to easily view a different pattern, a "new" star near Y Oph, and I thought "oops... wrong field?" But no, by the eyepiece there are all comps used for several months and RS Oph brighter.

In my astronomical yearbook for 2021, a page 162, I wrote: "according Bradley Schaeffer theoretic model, it's possible that RS Oph will experience a new eruption in 2021 or few years after it.

Alex!

Affiliation
None
Re:

Me too Alex, I was doing a regular nova patrol with my Canon 6D DSLR, when I checked the field I thought I centered  it wrong !

I rechecked and could see  RS Ophiuchi was indeed in outburst, I immediately grabbed my 20x100mm binoculars and could see this was so. 

 

A wonderful find for us both !!

Keith.

Affiliation
American Association of Variable Star Observers (AAVSO)
RS Oph

I observed RS Oph with the naked eye and estimated: +4.6 mag. I took photos from my small homeland - from Yuzhno-Morskoy (near Nakhodka), Russia, on August 9, 2021, from 15:19 to 15:22 UT. I have been waiting for several hours for gaps in the clouds, and sky cleared only for a few minutes.

My photos: https://twitter.com/romanov_filipp/status/1424787419740741633 and https://www.flickr.com/photos/filipp-romanov/51367649821

With best regards, Filipp Romanov.

Affiliation
American Association of Variable Star Observers (AAVSO)
Alert Notice 752: Rare Outburst of RS Oph

Congratulations to AAVSO observers Alexandre Amorim (AAX), Eddy Muyllaert (MUY), and Keith Geary (GKI) for catching the current outburst of RS Oph all independently and within an hour of each other!

To read more, see Alert Notice #752: https://www.aavso.org/aavso-alert-notice-752

There are threads for this object under the following forums:

- Time Sensitive Alerts: https://www.aavso.org/outburst-rs-ophiuchi
- Novae: https://www.aavso.org/rs-ophiuchi
- Cataclysmic Variables: https://www.aavso.org/outburst-rs-ophiuchi
- Spectroscopy: https://www.aavso.org/rs-oph-outburst-2021

Please subscribe to these threads if you are observing this nova so you can be updated as to its behavior and any observing campaigns on it. Join in the discussion or ask questions there!

Even better, get out and observe it!

Clear Skies,
Sara

Affiliation
None
Re:

Hi all, I have observed RS Ophiuchi again tonight at 2307 UT August 9th 2021 with  my 20x100mm binoculars, I estimated it’s visual magnitude at 4.8. 

It struck me that to me there is a change in colour - the star was initially blue in early outburst, I now saw a pale yellow colour.

Keith.

Affiliation
Nucleo de Estudo e Observacao Astronomica - Jose Brazilicio de Souza (Florianopolis, Brazil) (NEOA-JBS)
Similar view, Keith.Today…

Similar view, Keith.

Today my sky is not too good, with some cirrus. But I noted RS Oph yellowish. First using 10x50 binoculars. Through 90mm f/10 refractor it was easy to detect its color, some different from yesterday when I observed a white star.

My estimate for today, August 9, is 5.0, by 10x50B.

I did another estimates, but I'll send to AID.

With regards

AAX

Affiliation
Nucleo de Estudo e Observacao Astronomica - Jose Brazilicio de Souza (Florianopolis, Brazil) (NEOA-JBS)
Comparing two outbursts:

Comparing two outbursts:

Using WebObs data, 

In 2006

last visual observation before outburst

2006-02-10 06:00 UT m = 10.9 MED

first visual observation of the outburst

2006-02-13 03:54 UT m = 4.8 RWG

difference +2,91 days (or c. 70 hours)

 

Now
last visual observation before outburst

2021-08-07 23:15 UT m = 11.2 AAX

first visual observation of the outburst

2021-08-08 20:52 UT m = 5.1 MJZ

difference +0.9 days or 21,6 hours

But in August 8, between 13:47 and 15:27 UT, Lou and Wang catched the star rising from 9.1 to 7.0 in V.

Amazing!

Affiliation
None
Re:

Alex, thanks for the information regarding the timiline in UT between your observation and what followed. Going by what is given here, you were very close to witness the very beginning of the outburst ! Assuming it took less than two hours to rise from magnitude 9.1 to 7.0, it must have started around 1200UT August 8th. 

How did you find out about Lou & Wang's observations? 

Amazing !

Keith.

Affiliation
Astronomical Society of South Australia (ASSAU)
An unexpected post about recurrent novae

Hi all

Like many, I've enjoyed observing RS Oph, submitting a few binocular visual observations to AID and writing a post or three:

  • https://strangequark.me/2021/08/16/rs-ophiuchi-decline-continues/
  • https://strangequark.me/2021/08/12/recurrent-nova-rs-ophiuchi-update/
  • https://strangequark.me/2021/08/10/recurrent-nova-rs-ophiuchi-in-outburst/

Last week I was asked to give a brief talk by the president of our local club (https://www.assa.org.au) at the next meeting about RS Oph.

While researching RS Oph and recurrent novae in general, I came across this nice post on CVNet by Mike Simonsen in his usual enthusiastic style:

  https://sites.google.com/site/aavsocvsection/articles/recurrentnovae

He was larger than life, that's for sure.

Anyway, I just wanted to share that.

David