Image Credit: JAXA, ISAS, DARTS; Processing & Copyright: Damia Bouic

Akatsuki is a Japan Aerospace Exploration Agency (JAXA) mission. They maintain a user access site at http://darts.isas.jaxa.jp/planet/project/akatsuki/ with PDS acting as a mirror site.

News
2019-06-01
  • New releases of UVI and LIR data sets including L1b, geometry information, and L2 products are available. This release contains data acquired from 2010-05-21 to 2018-06-03. The current status of these products is "in peer review". Please refer Release Notes file for the detailed list of changes.
  • IR1, IR2, and RS data sets are updated. The current status of these data sets is "in peer review". Please refer Release Notes file for the detailed list of changes.


2019-03-05
  • 3rd release of VCO SPICE data set is available.


2018-12-28


2018-12-01
  • The 4th release of L1b, L2b, and L2c products for UVI and LIR are available. This release contains data acquired from 2010-05-21 to 2017-12-10. The current status of these products is "in peer review", so please use at your own risk.
  • The 2nd release of Level 3 (L3b and L3c) products for UVI and LIR are available. This release contains data acquired from 2010-12-09 to 2017-12-10. The current status of these products is "release candidate" because these products are based on data sets with the status, "under review".
  • IR1 and IR2 data sets are updated. The current status of these data sets is "in peer review" or "release candidate", so please use at your own risk.
  • The 2nd release of L2, L3, and L4 products for RS are available. This release contains data acquired from 2016-03-03 to 2017-08-11. The current status of these products is "in peer review", so please use at your own risk.


On this Page:
Overview
Accessing Data



Related Papers Please see list of publications of AKATSUKI


Overview

Also known as Venus Climate Orbiter (VCO) and PLANET-C, Akatsuki was successfully launched at 21:58:22 (UTC) on May 20, 2010. The main goal of the mission was to understand the Venusian atmospheric dynamics, super-rotation, and cloud physics, with the explorations of the ground surface and the interplanetary dust given lesser priority. Four cameras with narrowband filters imaged Venus at different wavelengths to track the distributions of clouds and minor gaseous constituents at different heights or to study the Venusian atmospheric dynamics in three dimensions. High cadence explorations of lightning and airglow, as well as radio occultation atmospheric profiling were also performed. After failure to gain orbit in December 2010, after orbiting the sun for five years, orbit insertion was obtained on December 7, 2015 by using the reaction control system. Akatsuki was inserted into a near equatorial orbit and maneuvered into an elliptical orbit with apoapsis altitude ~370,000 km and periapsis altitude of 1,000 -- 10,000 km, and a period of ~11 days.

Accessing Data

UVI - Ultraviolet Imager --Si-CCD (1024 X 1024 pixels) -- Field of View: 12° X 12°

UVI obtained images from April 2016 through June 6, 2018 through narrow bandpass filters centered at the 283 and 365 nm wavelengths to map the SO2 distribution and analyze cloud motions using images obtained typically at 2-hr intervals to map wind vectors. The UVI images have spatial resolutions ranging from 200 m to 86 km at sub-spacecraft points with signal-to-noise ratios of over 100 after onboard desmearing processing.

Raw Data
Calibrated Data
Geometry


Citation - When you publish your own work based on the AKATSUKI UVI data, please refer to the following paper(s) or the data sets:



Yamazaki, A., M. Yamada, Y.-J. Lee, S. Watanabe, T. Horinouchi, S. Murakami, T. Kouyama, K. Ogohara, T. Imamura, T. M. Sato, Y. Yamamoto, T. Fukuhara, H. Ando, K. Sugiyama, S. Takagi, H. Kashimura, S. Ohtsuki, N. Hirata, G. L. Hashimoto, M. Suzuki, C. Hirose, M. Ueno, T. Satoh, T. Abe, N. Ishii, and M. Nakamura, Ultraviolet imager on Venus orbiter Akatsuki and its initial results, Earth, Planets and Space, 70, 23, doi:10.1186/s40623-017-0772-6, 2018. URL (Open Access)

Murakami, S., M. Yamada, A. Yamazaki, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER UVI RAW DATA V1.0, VCO-V-UVI-2-EDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., M. Yamada, A. Yamazaki, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER UVI CALIBRATED DATA V1.0, VCO-V-UVI-3-CDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., M. Yamada, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER UVI GEOMETRY INFORMATION V1.0, VCO-V-UVI-3-SEDR-V1.0, NASA Planetary Data System, 2018.


Data Processing Tools - See the JAXA Site




IRI - 1 μm Camera - Si-CSD/CCD (1024 X 1024 pixels) - Field of View: 12° X 12° IR1 obtained images from April 2016, until December 09 2016 when the driving electronics for both IR1 and IR2 failed. More than 600 dayside images and about 150 nightside images (limited due to light scattered from the bright dayside) were obtained. The 0.90-μm dayside images are of sufficient quality to retrieve the wind field in the cloud region and the quality of the nightside 1.01-μm images is sufficient for a search for active volcanism. The quality of the 0.97-μm images may be insufficient to achieve the expected spatial resolution for the near-surface H2O mixing ratio retrievals.

Raw Data
Calibrated data
Geometry


Citation - When you publish your own work based on the AKATSUKI IR1 data, please refer to the following paper(s) or the data sets:



Iwagami, N., S. Takagi, S. Ohtsuki, M. Ueno, K. Uemizu, T. Satoh, T. Sakanoi, G. L. Hashimoto, Science requirements and description of the 1 μm camera onboard the Akatsuki Venus Orbiter, Earth, Planets and Space, 63, 487-492, doi:10.5047/eps.2011.03.007, 2011. URL (Open Access)

Iwagami, N., T. Sakanoi, G. L. Hashimoto, K. Sawai, S. Ohtsuki, S. Takagi, K. Uemizu, M. Ueno, S. Kameda, S. Murakami, M. Nakamura, N. Ishii, T. Abe, T. Satoh, T. Imamura, C. Hirose, M. Suzuki, N. Hirata, A. Yamazaki, T. M. Sato, M. Yamada, Y. Yamamoto, T. Fukuhara, K. Ogohara, H. Ando, K. Sugiyama, H. Kashimura, T. Kouyama, Initial products of Akatsuki 1-μm camera, Earth, Planets and Space, 70, 6, doi:10.1186/s40623-017-0773-5, 2018. URL (Open Access)

Murakami, S., M. Yamada, A. Yamazaki, S. Ohtsuki, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR1 RAW DATA V1.0, VCO-V-IR1-2-EDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., S. Ohtsuki, S. Kameda, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR1 CALIBRATED DATA V1.0, VCO-V-IR1-3-CDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., M. Yamada, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR1 GEOMETRY INFORMATION V1.0, VCO-V-IR1-3-SEDR-V1.0, NASA Planetary Data System, 2018.


Data Processing Tools - See The JAXA Site




IR2 - 2 μm Camera - PtSi-CSD/CCD (1024 X 1024 pixels) – Field of View: 12° X 12°

IR2 obtained images from April 2016 until December 09 2016. The single-stage Stirling cycle cryo-cooler of IR2 was operated with various driving voltages to achieve the best possible cooling under the given thermal environment. Dayside images at 2.02 μm and night-side images at 1.735, 2.26, and 2.32 μm were acquired. Additionally, images of stars for calibration and dark images for the evaluation of noise levels were obtained. Low-frequency flat images (not available in pre-launch calibration data) were constructed using the images of Venus acquired from near the pericenter to establish the procedure to correct for the IR2 flat-field response. Techniques for dealing with scattered light were developed and detailed astrometry, performed on star-field images in the H-band (1.65 μm), confirmed that the geometrical distortion of IR2 images was negligible.

Raw
Calibrated data
Geometry

Citation - When you publish your own work based on the AKATSUKI IR2 data, please refer to the following paper(s) or the data sets:


Satoh, T. M. Nakamura, M. Ueno, K. Uemizu, M. Suzuki, T. Imamura, Y. Kasaba, S. Yoshida, M. Kimata, Development and in-flight calibration of IR2: 2-μm camera onboard Japan's Venus orbiter, Akatsuki, Earth, Planets and Space, 68:74, doi:10.1186/s40623-016-0451-z, 2016. URL (Open Access)

Satoh, T., T. M. Sato, M. Nakamura, Y. Kasaba, M. Ueno, M. Suzuki, G. L. Hashimoto, T. Horinouchi, T. Imamura, A. Yamazaki, T. Enomoto, Y. Sakurai, K. Takami, K. Sawai, T. Nakakushi, T. Abe, N. Ishii, C. Hirose, N. Hirata, M. Yamada, S. Murakami, Y. Yamamoto, T. Fukuhara, K. Ogohara, H. Ando, K. Sugiyama, H. Kashimura, S. Ohtsuki, Performance of Akatsuki/IR2 in Venus orbit: the first year, Earth, Planets and Space, 69, 154, doi:10.1186/s40623-017-0736-x, 2017. URL (Open Access)

Murakami, S., T. Satoh, M. Yamada, A. Yamazaki, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR2 RAW DATA V1.0, VCO-V-IR2-2-EDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., T. Satoh, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR2 CALIBRATED DATA V1.0, VCO-V-IR2-3-CDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., M. Yamada, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER IR2 GEOMETRY INFORMATION V1.0, VCO-V-IR2-3-SEDR-V1.0, NASA Planetary Data System, 2018.


Data Processing Tools - See The JAXA Site



LIR - Long-wave Infrared Camera - uncooled micro bolometer array 328 X 248 pixels – Field of View 16° X 12°

LIR obtained images from December 7, 2015 until June 3, 2018. However, brightness temperature derived from LIR 8-12 μm images contained an unexpected bias due to a thermal condition of the instrument. The bias could be partially eliminated by keeping the power supply unit active, while the residual bias was simply correlated with the baffle temperature. Therefore, deep-space images were acquired at different baffle temperatures on orbit, and a reference table for eliminating the bias from images was prepared. In the corrected images, the brightness temperature was ~ 230 K at the center of the Venus disk, where the effect of limb darkening is negligible. The result is independent of the baffle temperature and consistent with the results of previous studies.

Raw Data
Calibrated data
Geometry

Citation - When you publish your own work based on the AKATSUKI LIR data, please refer to the following paper(s) or the data sets:



Taguchi, M., T. Fukuhara, T. Imamura, M. Nakamura, N. Iwagami, M. Ueno, M. Suzuki, G. L. Hashimoto, K. Mitsuyama, Longwave infrared camera onboard the Venus Climate Orbiter, Adv. Space Res., 40, 861-868, doi:10.1016/j.asr.2007.05.085, 2007. URL

Fukuhara, T., M. Taguchi, T. Imamura, M. Nakamura, M. Ueno, M. Suzuki, N. Iwagami, M. Sato, K. Mitsuyama, G. L. Hashimoto, R. Ohshima, T. Kouyama, H. Ando, M. Futaguchi, LIR: Longwave Infrared Camera onboard the Venus orbiter Akatsuki, Earth Planets Space, 63, doi:10.5047/eps.2011.06.019, 1009-1018, 2011. URL (Open Access)

Fukuhara, T, M. Taguchi, T. Imamura, A. Hayashitani, T. Yamada, M. Futaguchi, T. Kouyama, T. M. Sato, M. Takamura, N. Iwagami, M. Nakamura, M. Suzuki, M. Ueno, G. L. Hashimoto, M. Sato, S. Takagi, A. Yamazaki, M. Yamada, S. Murakami, Y. Yamamoto, K. Ogohara, H. Ando, K. Sugiyama, H. Kashimura, S. Ohtsuki, N. Ishii, T. Abe, T. Satoh, C. Hirose, N. Hirata, Absolute calibration of brightness temperature of the Venus disk observed by the Longwave Infrared Camera onboard Akatsuki, Earth, Planets and Space, 69:141, doi:10.1186/s40623-017-0727-y, 2017. URL (Open Access)

Murakami, S., T. Kouyama, T. Fukuhara, M. Yamada, A. Yamazaki, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER LIR RAW DATA V1.0, VCO-V-LIR-2-EDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., T. Kouyama, T. Fukuhara, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER LIR CALIBRATED DATA V1.0, VCO-V-LIR-3-CDR-V1.0, NASA Planetary Data System, 2018.

Murakami, S., M. Yamada, K. McGouldrick, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER LIR GEOMETRY INFORMATION V1.0, VCO-V-LIR-3-SEDR-V1.0, NASA Planetary Data System, 2018.


Data Processing Tools - See The JAXA Site



RS – Radio Occultations

The radio occultation experiment delivered Bending Angle Profiles and Temperature/Pressure profiles from March 3, 2016 to August 11, 2017. An onboard ultra-stable oscillator (frequency: 38 MHz - Transmission frequency: 8.4 GHz) was used to generate stable X-band downlink signals needed for the experiment. Temperature profiles were successfully obtained down to ~ 38 km altitude and show distinct atmospheric structures depending on the altitude. The ionospheric electron density profiles were also successfully retrieved, showing distinct local time dependence. Akatsuki RS mainly probes the low and middle latitude regions thanks to the near-equatorial orbit in contrast to the previous radio occultation experiments using polar orbiters. Publication - Imamura et al., 2017, Earth, Planets, Space, 69:137, doi:10.1186/s40623-017-0722-3

Raw Supporting Data
Derived Atmospheric Profiles

Citation - When you publish your own work based on the AKATSUKI RS data, please refer to the following paper(s):



Imamura, T., T. Toda, A. Tomiki, D. Hirahara, T. Hayashiyama, N. Mochizuki, Z. Yamamoto, T. Abe, T. Iwata, H. Noda, Y. Futaana, H. Ando, B. Häusler, M. Pätzold, A. Nabatov, Radio occultation experiment of the Venus atmosphere and ionosphere with the Venus orbiter Akatsuki, Earth, Planets and Space, 63, 493-501, doi:10.5047/eps.2011.03.009, 2011. URL (Open Access)

Imamura, T., H. Ando, S. Tellmann, M. Pätzold, B. Häusler, A. Yamazaki, T. M. Sato, K. Noguchi, Y. Futaana, J. Oschlisniok, S. Limaye, R. K. Choudhary, Y. Murata, H. Takeuchi, C. Hirose, T. Ichikawa, T. Toda, A. Tomiki, T. Abe, Z. Yamamoto, H. Noda, T. Iwata, S. Murakami, T. Satoh, T. Fukuhara, K. Ogohara, K. Sugiyama, H. Kashimura, S. Ohtsuki, S. Takagi, Y. Yamamoto, N. Hirata, G. L. Hashimoto, M. Yamada, M. Suzuki, N. Ishii, T. Hayashiyama, Y. J. Lee, M. Nakamura, Initial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki, Earth, Planets and Space, 69, 137, doi:10.1186/s40623-017-0722-3, 2017. URL (Open Access)

Murakami, S., H. Ando, T. Imamura, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER RS DOPPLER PROFILES V1.0, VCO-V-RS-3-OCC-V1.0, NASA Planetary Data System, 2018.

Murakami, S., H. Ando, T. Imamura, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER RS BENDING ANGLE/TEMP/PRESSURE PROFILES V1.0, VCO-V-RS-5-OCC-V1.0, NASA Planetary Data System, 2018.


Data Processing Tools - See The JAXA Site



LAC - Lightning and Airglow Camera - 8 X 8 APD matrix array – Field of View 16° X 16° Delivery of data delayed


LAC was designed to observe the light curve of possible flashes at a sufficiently high sampling rate to discriminate lightning from other sources and could perform a more definitive search for optical emissions. LAC began lightning survey observations at 777.4 in December 2016.

Publication - Takahashi et al., 2018, Earth, Planets, Space, 70:88 doi:10.1186/s40623-018-0836-2

Data Delivery pending

Citation - When you publish your own work based on the AKATSUKI LAC data, please refer to the following paper(s):



Takahashi, Y., J. Yoshida, Y. Yair, T. Imamura, M. Nakamura, Lightning detection by LAC onboard the Japanese Venus climate orbiter, Planet-C, Space Sci. Rev., 137, 317-334, doi:10.1007/s11214-008-9400-x., 2008. URL

Murakami, S., M. Imai, M. Sato, Y. Takahashi, Y. Yamamoto, G. L. Hashimoto, VENUS CLIMATE ORBITER LAC RAW DATA V1.0, VCO-V-LAC-2-EDR-V1.0, NASA Planetary Data System, 2018. Pending


Data Processing Tools - See The JAXA Site



Accessing SPICE data
Archived SPICE Data Sets

WebGeocalc provides a convenient access to SPICE kernels – See Venus Climate Observer