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HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0309

Mercury Transit: Full Disk XRT observations and central meridian pointing

plan term


@ @


 name : Reeves, Yaji, Takeda, Katsukawa @  e-mail : kreeves[at]cfa.harvard.edu, kentaro.yaji[at]nao.ac.jp, takeda[at]mithra.physics.montana.edu, reale[at]astropa.unipa.it, yukio.katsukawa[at]nao.ac.jp

contact person in HINODE team

 name : Savage @  e-mail : sabrina.savage[at]nasa.gov

 abstract of observational proposal
Main Objective:
We will take full-disk XRT images during the Mercury Transit for education purposes, and also as a check of the XRT PSF used in prior studies of the transit of Venus in 2012.

Scientific Justification:
The transit of Mercury is good chance to measure one astronomical unit (1AU), the distance between the Earth and the Sun, from groud-based observations in schools or in the astronomical education community. For this purpose, full disk XRT images are needed. Additionally, recent work on the transit of Venus has found some residual X-ray signal in the atmosphere of that planet (Masoud et al, submitted). This observation will serve as a check on the XRT PSF used in that measurement. Additionally, a central meridian pointing at Mercury is useful for SOT to compare polarization signals around the planet with Venus.

 request to SOT
At central meridian pointing:
SP normal map sit-and-stare for ~5 mins

 request to XRT
At Disk Center pointings:
1) take Al-poly full-res full-Sun image triplet(128/8192/16384ms).
2) readout 768x384 region centered at (-500,-320) with Al-poly
full-res (4096/11571ms), 28 times at 30sec cadence.
3) repeat (1)
4) same as (2) but readout centered at (300,-320).
At Mercury pointings:
As requested by HOP 303.

 request to EIS

 other participating instruments
IRIS Requests: None.

Additional instrument coordination: None.

Previous HOP information:
The Venus Transit HOP (209) produced a variety of papers and EPO products.

Date & Time: May 9, 10:41 UT - 20:06 UT
Target(s) of Interest: Mercury and disk center

Period 1 (10:41--11:54) : Limb or Mercury pointing. [73min]
(see Mercury approaching the Sun, Mer.contact-I at 11:11)

Period 2 (12:19--13:32) : Disk Center pointing [73min]
(XRT full-Sun with readout on Mercury)

Period 3 (13:58--15:11) : Mercury pointing [73min]
(Mercury Central Meridian passage at ~15:00)

Period 4 (15:55--16:49) : Disk Center pointing [54min]
(XRT full-Sun with readout on Mer.)

Period 5 (17:31--18:28) : Mercury pointing [57min] (or DC?)
(Mer.cont-III and -IV at 18:40 and 18:43 occur during s/c night)

Period 6 (19:08 -- 20:06) : Limb pointing [58min]
(see Mercury going away from the Sun, no disk passage.)

Web page with more info:

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