Venus Transit 2004France

Thierry Midavainethimidav@club-internet .fr

Club Eclipse AFAVT2004 7-9 may 2004 / Prague

Head lines

French Association NetworkTechnical preparationWeather issuesTime keepingObservation and recordingDissemination

French National Associations

AFANetworking of 170 local astronomical associations as Nuit

des Etoiles event“Ciel et Espace” june issue with several papersConcoursRencontres du Ciel et de l’Espace 2004

SAFEdition of a dedicated issue of « L’ASTRONOMIE »

Other National Associations

Planète Science Dedicated to support young and student groups

CLEA (Comité de Liaison Enseignant Astronome)

Web site Network of french teachers and college class from

Spitzberg to La Réunion island.

AUDE ...

Club Eclipse

16 members from Paris areaActivities around experimental projectsMissions in Observatories 60cm class

telescopesTransient events

Phemu Occultation by asteroids and satellites

Detectors and acquisition process

Technical Preparation

Systeme features Location: Long Lat Alt in WGS84 frame, Time keeping Optic:Filter transmission, Pupil diameter, focal length Size and pitch of the detector Spectral bandwidth frame rate frame recording format

Exploitation process

Weather issues: Moving or not Theyr, GFS

Time keeping at 1 sec accuracy

Quartz ClockAtomic Clock through a communication link

Allouis emitter (French railway network) LW radio France Inter Speaking Clock through phone link Internet:NTP Tardis, Dimension 4 DCF 77 GPS

Internal clock from PC

NTP/GPS Comparison(Guillaume Dubos)

écartTC-DC77

0.00066

0.000665

0.00067

0.000675

0.00068

0.000685

0.00069

0.000695

0.0007

numéro d'image

eca

rt e

n f

ract

ion

de

jo

ur

écartTC-DC77

Drift between the 15Hz frame rate of a Web cam and 1Pulse /sec from DCF77

Acoustic timing

Synchronisation test video/sound track

Antenne

Web-cam PC

Microphone

HP

1kHz

Questions about the Venus Transit?

Is there is a real black drop effect? Or on the contrary a white or colored ring effect due to Venus atmosphere?

Does the contact occures simultaneously in every color, H, and Infrared due to sun atmosphere refraction

Dissemination after the event

Rencontres du Ciel et de l ’Espace

Paris 12, 13, 14, nov 2004 Call for paper for a Venus Transit session