News

Scientific papers, radial velocities and eShel

Scientific papers, radial velocities and eShel   SHELYAK Instruments has sold many eShel to professional observatories around the world. The results enable our clients to advance science with paperss. We do not systematically refer to these papers because there...

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Making Science with an Alpy

Making Science with an Alpy The last paper in Astronomy & Astrophysics magazine (A&A) “New outburst of the symbiotic nova AG Peg after 165 years “ is based on spectra collected by observers from all around the world (12 nations represented) with...

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Spectro Star Party OHP 2017

Spectro Star Party OHP 2017 Like every year for more that 10 years, we actively participated to the OHP 2017 spectro star party. This meeting takes place in the wonderful site of Observatoire de Haute Provence (http://www.obs-hp.fr/welcome.shtml). This year, it was...

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Spectroscopy : practical guide

Spectroscopy : practical guide The french version of the book is now a reference in the Astronomical community. It has been rewarded by a lot of great comments from readers, and papers in magazines. It is now available in english : Successfully Starting in...

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Symbiotics stars

Symbiotics stars Recommended equipment : Star Analyser, Lhires III, eShel, Alpy, Lisa Time : one night or a life time ! Summary Symbiotic stars are interacting binary red giant & hot stars. The red giant loose material which is accreted by the hot star...

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Del Sco : 2011 campaign for periastron

Del Sco : 2011 campaign for periastron Be stars are hot, non supergiants stars whose spectra have shown or still show spectral emission in Balmer line - typically Halpha. Those emissions comes from material around the star - often an equatorial disk or ring. Those...

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Beta Lyrae – Shelyak !

Beta Lyrae - Shelyak ! Well... beta Lyrae is a special star for us as its arabic name is Shelyak, the origin of the Shelyak Instruments company name. Few years ago, we spent couple of week studying this star spectroscopically. This is a Be star (see article about this...

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Be stars

Be stars Recommended equipment : Lhires III, eShel, Lisa, Alpy Time : one evening to a life time ! Abstract Classical Be stars are non supergiant B-type stars that exhibit or have exhibit emission lines over the photospheric spectrum. This article review common...

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Beta Aurigae spectroscopic binary

Beta Aurigae spectroscopic binary Recommended equipment : Lhires III, eShel Time : several observing nights Summary Grâce à la haute résolution du Lhires III, il est possible de séparer de nombreuses étoiles binaires spectroscopiques. Ces étoiles, qui n'apparaissent...

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RV (Radial Velocity)

RV (Radial Velocity) Recommended equipment : eShel, Lhires III Time : 1 h  Stars are moving into space and their spectra appear shifted compared to the same lines in laboratory. Exemple here is SAO104807 which is moving toward us at a speed of 100 km/Sec and SAP112958...

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Lithium star : 59 Vir

Lithium star : 59 Vir Recommended equipment : eShel, Lhires III Time : one evening (acquisition) 59 Vir is a G0V type star, close to solar spectral type. But its spectrum display a stroing Li I (6708) absorption line. This star is rather young and lithium will...

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Measure star temperature

Measure star temperature Recommended equipment : Lhires III, eShel, Lisa, Alpy, Star Analyser Time : 4h French philosopher Auguste Compte (1798-1857) became very famous when he wrote in 1835 about stars: "... we will never know, by any mean, chemical composition of...

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L3 workshop

L3 workshop Equipment  : Spectrum reduction software Time : 1 day This part is in french only - it is about a workshop for License L3 students from Rennes astronomical club & university in France...

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Spectral classification (high resolution)

Spectral classification (high resolution) Recommended equipment : Lhires III, eShel Durée : 1 night Introduction Low resolution spectroscopy allows to classify stars and measure their effective temperature. But this method is limited and hgih resolution spectroscopy...

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Spectral classification (low resolution)

Spectral classification (low resolution) Recommended equipment : Lhires III, Star Analyser, Alpy, LISA, eShel Time : 1 night Spectroscopy is a great tool to compare stars between themselves and determine their spectral class - thus their effective temperature. In low...

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Planet’s rotation

Planet's rotation Recommended equipment : Lhires III, eShel Time : one evening (acquisition), 4h (analysis in group) Introduction Doppler-Fizeau effect is particularly visible on Jupiter or Saturn spectra taken with Lhires III. One spectrum os Jupiter is enough to...

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Sodium in all its states !

Sodium in all its states ! Recommended equipment : Lhires III, eShel Time : 1h Sodium element has a nice spectral signature with two narrow lines in the yellow. Those lines, D1 & D2, are at wavelength 589.00nm and 589.59nm, split by about 6 angstroems only. You...

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Atmospheric sodium

Atmospheric sodium Recommended equipment : Lhires III, Lisa , Alpy Time : about 1h  (at sunset) 80km above our head is an atmospheric layer with sodium excited by our Sun. During the day, it is not visible as the solar spectrum is too bright. During the night, this...

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titre article 1 (en)

Patruelis, siquid per inprudentiam gestmquedscisceret, futurum laborum socovinciae diu fessae poscebant siquid per inprudentiam gestmquedscisceret, futurum laborum socovinciae diu fessae poscebant siquid per inprudentiam gestmquedscisceret, futurum laborum socovinciae...

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