content 22-November-2017 15:55:47

Coordinated Ground-based Venus Observation Campaign

21 May 2007

This year, about twenty teams of professional astronomers will perform optical through mm observations of Venus using different telescopes around the world. Between 23 May and 9 June 2007 (when Venus will be at maximum eastern elongation) a coordinated campaign will be held with a majority of the teams participating. Some of the teams perform observations outside the coordinated period to optimize the conditions for their specific purposes (such as the Venus phase, or apparent diameter).

During the 18-day long coordinated campaign, the apparent size of Venus increases from 19.7" to 23.5" and its phase lies between 80° and 90°. The ground-based observations are an important supplement to the data gathered by the Venus Express spacecraft which is currently orbiting Venus, and provide additional information on Venus's atmospheric characteristics.

The coordinated period also encompasses the second of two flybys of Venus by the MESSENGER spacecraft, which occurs on 5 June, at 23:10 UTC. NASA's MESSENGER mission is on its way to Mercury and uses several planetary gravity assists to reach the innermost planet. During the Venus flyby, it will perform science observations of the planet allowing for simultaneous measurements to be made with Venus Express.

Science Goals

During the coordinated ground-based campaign, observations by the different teams will focus on the atmosphere above Venus's cloud layer and will include:

  • Wind measurements at different altitudes
     - cloud top level: visible spectroscopy
     - mesosphere (90-105 km): mm/submm spectroscopy
     - thermosphere (120 km): 10 μm observations
  • Morphology of the mesosphere airglow emission (O, O2)
  • Mesospheric composition (H2O, SO, SO2, HCl)
  • Deep atmosphere nightside composition

An overview of the participating teams and their observation goals is given below, sorted by wavelength region and by observation date. Some of the proposals for observing time are still pending approval, also indicated in the overview.

Participating Teams

Team Telescope/Instrument Science Goal
Approval status / dates Venus day or night side
Bertaux OHP/AAA Upper cloud winds
23 May-9 Jun day
  Keck Observatory O2 airglow
25-30 May (3 out of 5 nights), 5 Jun night
Widemann OHP/Sophie Upper cloud winds
28 May-2 Jun day
Widemann CFHT/Espadons Upper cloud winds
2-3 Jul day
Luz VLT/UVES Upper cloud winds
Date not yet known day
Luz VLT/UVES Thermosphere Winds (O)
Date not yet known night
Lilensten TBL/Narval O 557+630nm emission
Requested night
Near Infrared
Iwagami IRTF/CSHEL HCl above cloud
25-31 May (18-21 HST)* day
Bailey AAT/ANU Deep atmosphere composition
31 May-6 Jun, 20-26 Jul night
Slanger IRTF/CSHELL O2 1.27 μm airglow
4-7 Jun night
Marcq IRTF/SPEX Deep atmosphere composition
13-16 Jun night
Ohtsuki IRTF/CSHEL O2 airglow
13-15 Jul (10:30-19 HST)* night
Young IRTF Cloud imaging K band
20-31 Jul, 1h per day night
10 μm
Crisp IRTF/TEXES Chemistry
16-18 Apr both
Fast IRTF/HIPWC Thermosphere winds + OCS
18-21 May both
Sornig Kitt Peak Thermosphere winds + SO2
26 May-4 Jun both
Mitsuyama IRTF/MIRSI Thermal imaging
9-12 Jul both
Sandor JCMT CO/temp./wind mesosphere,
21-22 Apr, 3, 9 & 10 Jun, 2-3 Jul, 25-26 Aug(?) both
Lellouch IRAM 30m CO/temp./wind mesosphere
31 May-1 Jun, (Aug?, Sep?) both
Sagawa Nobeyama CO/temperature/wind
31 May, 4 Jun both
Moreno IRAM PdB CO/temp./wind mesosphere
Requested (1-18 Jun, Nov) both
Hartogh HHT CO/winds
Requested both

* HST = Hawaiian Standard Time


AAT: Anglo-Australian Telescope (3.9 m), Siding Spring Mountain, north-western New South Wales, Australia
CFHT: Canada-France-Hawai'i Telescope (3.6 m), Hawai'i
HHT: Heinrich Hertz Submillimeter Telescope Observatory, Arizona, USA
IRAM: Radio telescope/ Institut de Radio-Astronomie Millimetrique, Spain
IRAM PdB: Radio telescope/ Institut de Radio-Astronomie Millimetrique: antennae at Plateau de Bures, France
IRTF: InfraRed Telescope Facility (3 m), Hawai'i
JCMT: James Clerk Maxwell Telescope, Hawai'i
Keck: Keck Telescope, Hawai'i
Kitt Peak: Kitt Peak National Observatory, Arizona, USA
Nobeyama: Nobeyama Radio Observatory, Japan
OHP: Observatoire de Haute Provence, (1.52 m and 1.93 m), France
TBL: Observatoire du Pic du Midi, Telescope Bernard Lyot, France
VLT: Very large Telescope, Chile

Venus Amateur Observing Project

Started already in early 2006, the Venus Amateur Observing Project (VAOP) for ground-based observations by amateur astronomers is running throughout the Venus Express mission. During the coordinated campaign by the professional astronomer teams (23 May-9 June), it will run in parallel. For details on how to participate in the VAOP project follow the link in the right-hand side navigation.

Last Update: 15 July 2013

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