Rho Cassiopeiae

[Clarry (Clayton)]

Folks, I was just reading that a star called Rho Cassiopeiae is the leading candidate for the next supernova explosion in our galaxy. I did a search for it in both Stellarium & Voyager but couldn't find it listed. Anyone aware if it's known by another name? I assume it's in the Cassiopeiae constellation and as such would not be visible from Australia.

[astroron (Ron)]

Originally Posted by Clarry

Folks, I was just reading that a star called Rho Cassiopeiae is the leading candidate for the next supernova explosion in our galaxy. I did a search for it in both Stellarium & Voyager but couldn't find it listed. Anyone aware if it's known by another name? I assume it's in the Cassiopeiae constellation and as such would not be visible from Australia.

Probably only far north
This is taken from "The Sky" version 5
SAO 35879
GSC 4009:2605, HIP 117863, PPM 42338, HD 224014, B+56 3111
Flamsteed-Bayer: 7-Rho Cassiopeiae
Spectral: F8Iavar
**** Data from Hipparcos Catalog ****
Proper motion (mas/yr): RA = -4.54, Dec = -3.45
Magnitudes Bt: 6.05, Vt: 4.64
Parallax: 0.280 mas, 3571.4286 pc
Distance: 11648.46 light-years, 736661342.15 astronomical units
Magnitude: 4.51
RA: 23h 54m 52.229s Dec: +57°33'29.937"
RA: 23h 54m 23.032s Dec: +57°29'57.776" (Epoch 2000)
Azm: 12°31'24" Alt: -57°51'14"
Rise: 10:30 Transit: 13:09 Set: 15:48
Position error: 0.37 mas
From GSC 4009:2460:
Angular separation: 00°01'01"
Position angle: +296°40'
I hope this helps
cheers

[Liz]

Originally Posted by Clarry

Folks, I was just reading that a star called Rho Cassiopeiae is the leading candidate for the next supernova explosion in our galaxy. I did a search for it in both Stellarium & Voyager but couldn't find it listed. Anyone aware if it's known by another name? I assume it's in the Cassiopeiae constellation and as such would not be visible from Australia.

Interesting Clarry. Will see if its visible from our fair skies ..... when the clouds have gone

[astroron (Ron)]

Hi Liz, the constellation is up during the day time so you will have to wait till later in the year

Rise: 10:30 Transit: 13:09 Set: 15:48

[Liz]

Originally Posted by astroron

Hi Liz, the constellation is up during the day time so you will have to wait till later in the year

Rise: 10:30 Transit: 13:09 Set: 15:48

Aah, no worries, thanks Ron

[Vanda (Ian)]

If one was a nova searcher would you not be photographing suitable galaxys to maximise your chances? eg: Maximise the number of stars seen?

[ngcles]

Hi Clarry,

Yep Rho Cassiopeiae (top marks to you for spelling the genitive correctly) is a very interesting and pretty rare type of star that we see (within astronomical time-frames) transiting a very brief transitional/evolutionary stage.

It would be visible from the northern half of Australia (quite to very low in the north) but only when that part of the sky (around 0hrs RA) is above the horizon at night-time (approx Sept to Dec is best).

There is lots of interesting info here:

http://stars.astro.illinois.edu/sow/rhocas.html

and here:

http://www.solstation.com/x-objects/rho-cas.htm

In my searches, I've found three different distance estimates -- they are all in excess of 7,000 ly distant and the highest is 11,650ly. It is too far away to measure directly using parallax. It is certainly one of the most distant stars visible to the naked eye and a member of that small, exclusive club of naked eye stars >2000ly distant.

As a matter of interest, AG Carinae (when it is fleetingly, occasionally visible to the naked eye -- it is a Luminous Blue Variable) is probably the most distant naked-eye star at about 20,000 ly.

Rho Cas is undoubtedly on the way to going kahblooie soon, but my money is on one of the most luminous stars in NGC 3603 -- Sher 25. Sher 25 is about 20,000 ly away and there is a substantial probability that it is somewhere in the last 20,000 years of it's life.


Best,

Les D

[Clarry (Clayton)]

Thanks for the info people. With 10000ly to 20000ly distance from the nearest potential supernova activity, we should be safe from any life threatening side effects. That's a relief, even if it's 20 millenniums in the future.
Further reading has reveled the Crab Nebula is the remnants of a supernova. Chinese records from 1054 show it's explosion was visible for months, even during the day. That would have been something to see.