Spectro Party OHP 2019 : retrospective

by Olivier Garde

The Spectro Star Party at Observatoire de Haute Provence in France took place from August 2sd to 7th, 2019 and hosted more than 50 attendes from very different levels. The weather allowed us to enjoy the 5 nights with differents spectro setup on the ground equipped with spectro Alpy 600, LISA, LHIRES III, the new spectrograph UVEX and an eShel setup.

This edition was very special and will remain to this day, one of the richest information and meetings on several points:


  • 18 new attendes, mostly beginners, but also a few people who already have strong knowledge of spectroscopy.
  • 27different setups installed in the field, very varied in terms of optics and spectrographs, an absolute record and which makes it the biggest world meeting of spectrographs on the ground to date.

  • Official presentation of UVEX spectrograph design by Christian Buil and the “Nice People” : Pierre Dubreuil, Alain Lopez, Stéphane Ubaud, Jean-Luc Martin and Pierre Thierry. Christian wrote a page on the use of UVEX with small diameter optics during this spectro party and can be viewed here.(in french only)
  • Use of the Python language in spectrography and automation of astronomical observations by François Cochard, Jacques Michelet, Ivan De Gennaro Aquino and Thibault Notargiacomo. Olivier Thizy and Stéphane Charbonnel also presented their automatic observatories.
  • Proposal to follow a particular target: RR Lyr, a pulsating star of a period more than 13 hours. In previous editions, we proposed a series of targets that each participant could achieve at his convenience during the 5 nights of observations, the challenge here was to observe the spectroscopic maximum at a specific day and time. Thus, a large number of spectra were made simultaneously by the participants, whether beginners or experienced and with spectrographs of different resolutions.

  • A call by Steve Shore to organize us in Pro / Am collaboration projects

Steve Shore’s speech at the end of a meal
(vidéo from Olivier Garde, duration 5’02)

Welcoming participants

This year, the priority was given to the “newcomers” who have not yet participated in a spectro party at OHP, so we were able to welcome 18 new attendes.

9 countries are represented with attendes coming from France but also from Italy, Portugal, Switzerland, Germany, Czech republic, The United Kingdom, United States and Australia.

Each participant received a bag containing various goodies and information.

A first meeting allowed to present the site, the schedule of the 6 days as well as the targets to be done in spectroscopy.

3 working groups were formed according to the spectrograph used:

  • An ALPY 600 group led by François Cochard
  • A LISA group led by Olivier Garde
  • A LHIRES III group led by Olivier Thizy and Valérie Desnoux


One day at the spectro party

Each day goes the same way, in the morning François Cochard offers a training workshop on the Demetra softwareThen at noon, lunch buffet at maison Jean Perrin. The afternoon is devoted to data processing but also conferences and presentations proposed by various speakers including Steve Shore on an initiation to stars astrophysics.

Then dinner at Jean Perrin’s house before being all on the ground for the spectra acquisition either in small groups around a setup dedicated to a spectrograph in particular, or with his own equipment and that until at sunrise for the most motivated ….

The program of this spectro party is available HERE

The Spectro Star Party is the unique opportunity to link, first, the beautiful site of the OHP with its historic domes and its Provencal climate and, second, the meeting between enthusiasts, beginners or confirmed. And this is all its strength: the amazing  place is transcended by the group’s friendliness, and vice versa. Present for the third year, I was able to enjoy every minute of night sky, all the information I was looking for and all the ideas that were given to me … And for the first time, I had the opportunity, in turn, to give advice and advice to neophytes present! And all this in an atmosphere at once serious and cheerful! What more can you ask for, if it does not last longer?

Thomas Petit - Prague (Czech republic)

Amateur astronomer, Planetary Nebulae Spectra Trackers (PNST)

Photo copyright : Valérie Desnoux

What to say … it was a while that I was waiting to participate in this famous OHP spectro-party. I was expecting a strong event, and well I was not disappointed and for good reason: this edition has fulfilled all my expectations. Of course, this format is always a good opportunity to progress technically, but beyond that, it’s mostly meetings with others people. Indeed, it is a great moment of mutual help, sharing of knowledge and experience. The spectro community is enriched day after day by new enthusiasts already very involved and ready to bring water to the mill. What impressed me the most is the possibility for the “amateur” world to practice a free, independent and universal scientific astronomy through technological solutions such as python, linux, the automation of observations, the project UVEX, international collaborations … I also hope in the long run to catch up the train and then hold the pace … because it is moving fast 😉 In short, after this kind of events, we  come out over-motivated. A redo ! “

Bertrand Guégan - Lyon (France)

Amateur astronomer, Club d’Astronomie de Lyon Ampère (CALA)

Photo copyright : Olivier Garde

Un atelier spectro sur l’UVEX

Durant la spectro party, on a parlé bien sur du tout nouveau spectro UVEX III. Christian Buil nous a proposé une réunion d’information sur ce projet open source dont les divers pièces mécaniques sont réalisées avec une imprimante 3D. Ce spectrographe dédié au proche UV grâce à sa conception à base de miroirs et non pas de lentilles permet d’explorer un domaine que les amateurs n’avaient pas la possibilité de réaliser avec des spectrographes “classiques”. L’UVEX II permet également de part sa conception, d’observer d’autres longueurs d’ondes comme le proche IR en changeant simplement de réseau.

Sur le terrain, 3 UVEX ont été utilisé sur des setup trés différents : sur un Maksutov Sky-Watcher de 127 mm ouvert à f/11,8, un C11 ouvert à f/d10 ou encore un RC de 305mm ouvert à f/d8.

Réunion sur l’UVEX III autour de Christian Buil
(Crédit photo : Olivier Garde)

RR Lyr : Animation of 30 spectra of 300s each taken with a UVEX spectrograph
1200gr/mm grating and a 25µm slit
(animation by Pierre Dubreuil)

Examples of spectra taken during the OHP spectro aprty

Photo Gallery of the 2019 edition

On the field with Nicolas, Thibault and Pierre
Photo copyright :Valérie Desnoux

Games and relaxation at the OHP swimming pool
Photo copyright : Olivier Garde

Lunch buffet at maison Jean Perrin
Photo copyright : Valérie Desnoux

Pascal Le Dû during PN conference
Photo copyright : Valérie Desnoux

Paul, Pierre and Stephane
Photo copyright :Valérie Desnoux

Olivier and Pascal
Photo copyright : Valérie Desnoux

Paul, François, Woody, David and their wives
Photo copyright : Valérie Desnoux

Steve Shore conference
Photo copyright : Valérie Desnoux

Pictorial work of Steve
Photo copyright : Valérie Desnoux

Thomas and Pascal discovering a PN
Photo copyright : Olivier Garde

Jim and Steve
Photo copyright : Olivier Garde

Christian, Stephane and Pierre around the UVEX
Photo copyright : Valérie Desnoux

Several setups on the field
Photo copyright : Olivier Garde

Christian Buil’s presentation
Photo copyright : Valérie Desnoux

Work meeting of PNST group
Photo copyright : Olivier Garde

Group picture (some people are missing …)
Photo copyright : Olivier GARDE

See you next year for new spectroscopic adventures.