https://www.astronomerstelegram.org/?read=15517
BL Lac-type object S4 0954+65
coordinates RA: 09 58 47.2452 Dec: +65 33 54.8194; ICRS J2000
Northern observers looking to stretch their spectroscopic distance limits might be interested to try this one:
"Since the beginning of April this year the BL Lac-type object S4 0954+65 (RA: 09 58 47.2452 Dec: +65 33 54.8194; ICRS J2000) has been showing increased activity both in the optical (ATel #15322; ATel #15344; ATel #15376; ATel #15380) - here also in polarized light (ATel #15414; ATel #15419) - and in the gamma-ray regime (ATel #15375).
In the optical the object reached new records in the R-band on 21 April - JD 2459691.24 with 13.20 mag (ATel #15344) as well as on 13 May - JD 2459712.6873 with 12.72 mag (ATel #15380).
In the following weeks the brightness decreased and moved in a range of about 14.7 to 15.8 mag (R-band).
Since 11 July the brightness of this object has been steadily increasing again and now has reached about 13.4 mag."
From a recent paper by Ahnen Et Al:
https://www.aanda.org/articles/aa/abs/2 ... 24-18.html
"This blazar has a disputed redshift of z = 0.368 or z ≥ 0.45 and an uncertain classification among blazar subclasses."
So perhaps more amateur spectroscopic observations could well add useful spectra to clarify the disputed redshift.
Cheers all,
Hamish
Brightening of Blazar BL Lac-type object S4 0954+65
-
- Posts: 227
- Joined: Thu Jun 20, 2019 12:11 am
Jump to
- Forum presentation
- ↳ Forum Description - INFORMATION FOR REGISTRATION
- ↳ General Topics, Annoucements, Forum Life
- ↳ Petites Annonces
- Current Campaigns
- ↳ AZ Cas
- ↳ RR Lyrae
- ↳ Be Stars survey
- ↳ P Cygni
- ↳ VV Cep
- ↳ B[e] FS CMa Objects Survey
- ↳ Archives
- ↳ SN 2011fe campaign
- ↳ Epsilon Aurigae
- ↳ Novae
- ↳ T Tauri Stars
- ↳ Planetary Nebulae
- ↳ Be Search
- ↳ CH Cygni
- Outbursts, Alerts, Monitoring
- ↳ Novae
- ↳ Symbiotic Stars
- ↳ Supernovae
- ↳ Cataclysmic Stars
- ↳ Be Stars
- ↳ Comets
- ↳ Resources
- ↳ Miscellanous
- Spectra, results, information on activity ...
- Spectroscopes and Softwares
- ↳ MatLab
- ↳ Python
- ↳ UVEX Project
- ↳ Documentation de référence
- ↳ Sol'Ex/Star'Ex
- ↳ Documentation de référence
- ↳ Software Demetra
- ↳ Software ISIS
- ↳ Software VisualSpec
- ↳ Software SpcAudace
- ↳ Software PlotSpectra
- ↳ asdb ARAS DataBase
- ↳ Android applis
- Astrophysics, Theory, Publications ...
- Beginners corner
- Introduction / Présentation
- What are you observing tonight ?
- ↳ OHP 2014
- ↳ OHP 2013
- ↳ OHP 2012