JAXA/Akatsuki – ESA/JAXA BepiColombo coordination during Venus flybys in Oct. 2020 and Aug. 2021

International collaboration on Venus observations are under discussions during the flybys of BepiColombo (ESA-JAXA), on its way to Mercury. The collaborative observations have been planned between BepiColombo and the operating Venus orbiter, Akatsuki (JAXA), during the 2 times of Venus flybys in October 2020 (Fig. 1) and August 2021, while its details are yet under discussions.

Dates of Venus flybys2020 October 15
(Fig. 2)
2021 August 10
(Fig. 3)
Closest approach time of BepiColombo
[hh:mn UTC]
~06:30~21:00
Local time of sub-
BepiColombo point
17:0014:00
Local time of sub-
Akatsuki point
18:0006:00
Local time of sub-
Earth point
08:0016:00
Distance of BepiColombo from the center of Venus
[km]
~17,000~7,000
Distance of Akatsuki from the center of Venus [km]~330,000~70,000
Distance of the Earth from the center of Venus
[AU]
~1.17~1.25
Operating instruments on BepiColombo
during the flyby
Mercury Planetary Orbiter (MPO):

ISA, MAG, MERTIS, MGNS, MORE, PHEBUS, SERENA, SIXS

Mercury Magnetospheric Orbiter (Mio):

MPPE, MGF, PWI 
Mercury Planetary Orbiter (MPO):

ISA, MAG, MERTIS, MGNS, MORE, PHEBUS, SERENA, SIXS

Mercury Magnetospheric Orbiter (Mio):

MPPE, MGF, PWI 
Operating instruments on Akatsuki at the time of BepiColombo’s flybyAkatsuki Orbiter
UVI and LIR
Akatsuki Orbiter
UVI (TBD), LIR (TBD)
Coordinated observation instrumentsPHEBUS (TBD)-UVI
MERTIS-LIR-UVI
PHEBUS-UVI (TBD)
MERTIS-LIR-UVI (TBD)

Table 1. Summary of observational conditions during the Venus flybys of BepiColombo. The detailed time and locations are subject to change.


Figure 1 – Overview of trajectories of BepiColombo and Akatsuki as seen from the north of the solar system. +X is assigned to the Sun. Red dots are the locations of BepiColombo and Akatsuki at the time of the closest approach (CA) of BepiColombo (2020-October-15). Green arrow indicates the direction of the Earth. Image is produced by Y.J.L.


F

Figure 2 – Visualized viewing geometries of Venus as seen from BepiColombo (left), Akatsuki (middle) and the Earth (right) at the time of 1stflyby on 2020 Oct 15. The background is the LIR images (Kouyama et al. 2017). The distance is from the center of Venus, green dots are the sub-observer points, and yellow dots are sub-solar points. Image is produced by Y.J.L.



Figure 3 – Visualized viewing geometries of Venus as seen from BepiColombo (left), Akatsuki (middle) and the Earth (right) at the time of 2ndflyby on 2021 Aug 10. The background is the LIR images (Kouyama et al. 2017). The distance is from the center of Venus, green dots are the sub-observer points, and yellow dots are sub-solar points. Image is produced by Y.J.L.


We gladly share this news to worldwide ground-based Venus observers for better coordination among observers, and encourage Venus observers to use this chance to achieve own scientific goals on Venus studies under collaboration with corresponding instrumental teams of BepiColombo and Akatsuki.


l. to r. : Flyby coordination team members Jörn Helbert, Yeon Joo Lee, Pedro Machado, Thomas Widemann, Valeria Mangano. DPS-EPSC conference, Geneva, 19 Sep. 2019.

Contact information: 

  • Contact for MERTIS: Dr. Jorn Helbert (co-PI), Joern.Helbert@dlr.de
  • Contact for PHEBUS: Dr. Eric Quemerais (PI), eric.quemerais@latmos.ipsl.fr
  • Contact for UVI: Dr. Takao M. Sato, sato.takao@do-johodai.ac.jp
  • Contact for LIR: Prof. Makoto Taguchi (PI), taguchi@rikkyo.ac.jp
  • General information on BepiColombo flybys: Dr. Valeria Mangano, valeria.mangano@inaf.it
  • General coordination with Akatsuki: Dr. Masataka Imai, masataka@ep.sci.hokudai.ac.jp
  • Information on the BepiColombo-Akatsuki coordination: Dr. Yeon Joo Lee (Y.J.L.), y.j.lee@astro.physik.tu-berlin.de

Links

EPSC-DPS press release – Sep 2019

ESA BepiColombo : Venus Takes Center Stage in October 2020 Observation Campaign – Sep. 2019

JAXA Akatsuki ground-based observations : information from Akatsuki team