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I've sent a request to Alain Klotz, TAROT and some observers in France for a photmetry support of FF cam. I need a B V measure in Jonhson-Cousin system. Message en Français pour un support photométrique sur FF cam Il s'avère d'aprés le suivis spectrométrique que cette étoile n'est pas une Be classique mais présente une variabilité spectrale hors du commun. Pas d'exemples connus à ce niveau de variabilité, profil et intensité. On échantillonne actuellement la période mais aprés un mois de mesures, avec un spectre échelle... [Lire la suite]

I've started a spectral monitoring of one my favorite star, FF cam. I discovered this star in 2009 by a routine survey of Be stars. Considering the Bess program, this star was observed only once par year before. I was surprised in 2009 in two consecutives nights, while redoing spectra due to bad SNR, to see how much the h alpha profile has changed. I did some others spectra in 2009 showing a great activities in H alpha and let it down for a while. At this time i was using a LhiresIII... [Lire la suite]

Je m'amuse toujours avec la camera ultra grand champs. Des angles differents, pendant de longues heures d'observation sur deux nuits pour epier le ciel et le télescope.

Following the HeII4686 and the HeI5876 here is the study of the HeII5411 line of the wolf rayet star WR134. I present a time serie of three spectra taken during a total exposure of 2H40, with 2X1h spectra and 1X40minutes for the last one. small active absorption features are readily visible at the top of the line and transient emission line appears at Vr 2200km/s.  SNR of a 3600s exposure is around 110 at 5471A, Resolving power is 12000, dispersion 0.1A. All spectra are corrected from instrumental response on... [Lire la suite]

I made a sky cam with a DMK31usb camera and a 24mm f1.8 Zuiko lens. First light during a whole observing session, about 8h of video, 1 image every minutes. The aim is sky monitoring during observation, detection of cloud and in the future, detection and photometry of transient phenomena. Note, a possible evolution is to use this cam as a large field camera, with astrometry refinement to point faint targets. We will see... Update, new cam, full moon New upgrade, All Sky cam with a 2.8mm f1.8 C-CS lens, crescent moon... [Lire la suite]

Following the study of HeII4686, here is the HeI 5876 extracted from an order of an eshell spectrum of 9600s exposure and sampled to 3600s and 7200s for comparison. SNR is better than in the blue region, normal with the better sensitivity of the ccd, SNR50 around 5972A. Straight absorption are Na-D interstellar absorption, with a bump inside. "The bumps in the core of the NaI D-lines is due to two present components. One forms in our spiral arm, the other one forms in the next spiral arm. Typically this is a sign of a... [Lire la suite]

Here is a study of the HeII4686 profile variation depending of the exposure time of WR134, a wolf rayet star subject of a 2013 pro am campaign from the Convento group The SNR requirement on 1hour exposure for this campaign is about 200. The resolution must be better than 1A, R5000 at HeII4686. Here is an individual order of an echelle spectra taken during the night of Dec, 12th. The sky conditions were excellent and the object was at 80° high at the beginning of exposures. 2H40 exposure were taken, under good seing and transparency.... [Lire la suite]

In 2010, August, i discovered an outburst of the Be star V442 and. That was my 2nd discovered outburst during 2010 on a total of three up to date. Unlike the others,  this outburst occurred during a period of nine month, between two observations, and last for less than 6 months. It was very short for a Be outburst. The star return to quiescent stage recently these days.  It gave some of the most animate Be spectra i have never done. Below are animations of my raw spectra, telluric lines... [Lire la suite]

I've finally managed to catch an échelle spectra of SN2011fe with my C14 spectrograph equipment (calling DeNise in the memories of my grand mother) observatories This spectra is the sum of 15 exposures of 900s taken in two nights, September 22 and 23. As seen here http://www.astrosurf.com/aras/surveys/supernovae/sn2011fe/obs.html the overall shape of the spectra doesn't change in this period. The SN was at 10.5 Vmag and low over the horizon.  The échelle spectrograph is an Eshell... [Lire la suite]

New observation and firstime supernova for me ! A light coming from 20 millons Ly ! At V mag nearly 10.5, this SN is in the range of both low and high resolution amateur spectroscopy. Cause of the doppler broadening effect, the spectral lines are very large and oversize my spectral domain, here around HeII 4686A. But tiny lines in the spectrum maybe insterstellar and intergalactic (!) absorption useful to calculate the extinction of the supernova and then the true brightness and distance (Diffuse interstellar bands (DIB): co-planar... [Lire la suite]