HOP list   Monthly Events

HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0218

Transit of Venus as Seen from Jupiter (JToV), 2012 September 20

plan term


@ @


 name : Pasachoff, Schneider, Reardon, Sterling @  e-mail : alphonse.sterling[at]nasa.gov

contact person in HINODE team

 name : Sterling @  e-mail : alphonse.sterling[at]nasa.gov

 abstract of observational proposal
As viewed from Jupiter, Venus will transit the Sun on 2012 September 20.  This will result in a decrease in the reflected solar irradiance off of Jupiter.  A separate proposal has been accepted by the Hubble Space Telescope (HST) team to observe Jupiter at multiple wavelengths with HST around and during the transit time in an attempt to detect the reflected-intensity drop.  During the transit time, it is possible that there will be subtle variations in that Jovian reflected intensity level resulting from Venus crossing specific solar features (e.g., sunspots).  This proposal is for Hinode  SOT observations to support the HST study by observing with high resolution the regions of the Sun that  reside along the path that will be covered by Venus as seen from Jupiter; that is, Hinode will observe the  ``footprint'' on the Sun of the Venus-as-seen-from-Jupiter track.

The potential Hinode observations  will be restricted to times if and when this footprint crosses the expected location of active regions.  Major Flare Watch observations, or other major Hinode observations, have a higher priority than these JToV observations.

The footprint of the JToV path of Venus across the Sun as seen from Hinode has been provided by a HOP team member (G. Schneider).  The JToV footprint will be visible from Hinode on 20 September 2012,   4:23 - 11:26 UT.  On that day, Venus as seen from Earth will be ~17'' in diameter, and hence this is the angular size of the deprojected JToV footprint of Venus.  Using this information, and assuming an SOT FOV of about 200'' X 100'', we  have determined the needed pointings for the period of time.  That information is given in the  Remarks section below.

The procedure will be for the CP and COs to consider whether and when the specified pointings will possibly contain an AR in the SOT FOV.  If possible, they will include pointings to the JToV target when the AR is  predicted to be in that FOV.  HOP member A. Sterling is to be Hinode Chief Planner (CP) on the upload days of Tuesday 18 Sep and Thursday 20 Sep. Sterling has talked with T. Yasuda, who will be CP for the preliminary planning on Monday 17 Sep.

 request to SOT
FOV: 218'' x 109'', 2x2 binned pixels.

Filters and programs:

- A minimum image sequence in Ca H (3968 Ang), G-band, and red continuum channel is requested.   These filters are desired because G-band and Ca show well features such as brightenings and sunspots, and the red continuum is included because one of the HST filters to be used is its F763M filter, which is in the red.  (A second filter to be used by HST is its F275W, which is in the UV.)

- As a minimum, two or three sequences per relevant pointing are requested.  These can be varied as telemetry  and other plans permit.  If time is available, relatively continuous coverage at low cadence can be run.

- Synoptics can be run as normal.

 request to XRT
No request

 request to EIS
No request

 other participating instruments
- Hubble Space Telescope (HST), observing albedo changes in the Jovian system in response to the transit.  The HST plan is at:



- ACRIMsat


- Pointing number, Time period (UT time on 20 Sep 2012), and Pointing-Center location:

(1)  04:23 -- 04:30 UT:         X=  -220.0"      Y= +133.0"
(2)  04:30 -- 04:45 UT:         X=  -75.0"       Y= +133.0"  
(3)  04:45 -- 05:12 UT:         X=  +100.0"      Y= +133.0"  
(4)  05:12 -- 05:50 UT:         X=  +275.0"      Y= +133.0"  
(5)  05:50 -- 06:38 UT:         X=  +445.0"      Y= +133.0"  
(6)  06:38 -- 07:40 UT:         X=  +615.0"      Y= +133.0"  
(7)  07:40 -- 09:13 UT:         X=  +795.0"      Y= +133.0"  
(8)  09:13 -- 11:26 UT:         X=  +900.0"      Y= +133.0"  

SOT/SC offset is not accounted for with these values.  It should be accounted for when generating the pointing table for the upload.

- Pointings should be considered when there is a possibility for the SOT FOV to cross active region locations.

HOP list   Monthly Events