spectro-aras.com

Observation of RS Oph by using a 65 mm refractor (2.5-inch) and Star'Ex at nearly maximal resolution of the setup; i.e. R=30 000 (for 8 x 600 sec. exposure): http://www.astrosurf.com/buil/forum27/_rsoph_20210817_835_1.png Detail of H-alpha peak (fading); well resolved and after H2O lines removal: ht...

The big advantage of a small telescope for observation of relative bright object -> the high spectral resolution. Here Star'Ex 2400 lines/mm grating, 19 microns slit on D=65mm f/6.5 refractor (TS) at R=24000 (one hour observation), 16.80/08/2021 : http://www.astrosurf.com/buil/forum27/_rsoph_2021081...

Three RS Oph observations night by using Star'Ex at the direct f/5 focus of a a 200 mm Newton (8-inch). 11.84 / 08 / 2021 : infrared by using a 600 lines/mm 750 nm blaze grating (R=1750) (note evolution of OI 8446 line relative to continuum): http://www.astrosurf.com/buil/forum27/_rsoph_20210811_842...

StarEx spectra of RS Oph for the 10-11 August from Antibes. StarEx is the stellar version of the low cost SolEx instrument dedicated to the solar observation (a 3D printing setup !). The spectrograph is on a 200-mm Newton telescope working at f/5. The Halpha region at R=1700 (600 lines/mm grating ve...

An idea of the actual magnitude, the object seem faint last night ?

Christian

Detection of Sodium tail from Mercury's exosphere, the May 17, 2021, by using a very low cost instrumentation, the Star'Ex spectrograph (1200 l/mm grating) on a 8-inch Newton telescope. About Star'Ex see: http://www.astrosurf.com/solex/sol-ex-stars-en.html . The result: http://www.astrosurf.com/buil...

A Star'Ex spectrum of comet C/2020 R4 on a 8-inch Newton reflector, taken the April 24.9, 2021: http://www.astrosurf.com/buil/forum26/_c2020_R4_2D.jpg The nucleus region spectrum profile (relative to a solar type star): http://www.astrosurf.com/buil/forum26/_c2020_r4_nucleus_20210424_904_1.png http:...

Robin, this is absolutely correct, a closer quasar would not have been visible because of the pollution!

Another magic thing: the quasar is impossible to see from my observatory in direct imagery, but visible with a spectrograph (it is not intuitive for beginners!).

Christian

Star'Ex spectrum the April 24.1, 2021:





(8-inch Newton f/5 telescope stopped at f/8 -> 3750-7100 A valuable spectral range).

Christian Buil

Robin, your observations of these distant quasars are fantastic. It is an achievement and it must raise enthusiasm! Your magnificent work inspired me to make an observation with the Star'Ex spectrograph (3D-printing) of the quasar J1654436, but unfortunately with a more modest telescope (8-inch Newt...