!!!Observing with EIS with the new antenna

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!!!Practical constraints?
!!Time
!OPPeriods
An OP Period[1] is the period of time during which an observing programme (''plan'') is defined. e.g. from 10:23 UT on 2008/05/02 to 11:19 UT on 2008/05/04

!Eclipse Season
During eclipse season, the line of sight between the spacecraft and the Sun grazes the Earth's atmosphere, causing attenuation (and ultimately complete absorption) of the light that would otherwise be seen by each of the instruments. This attenuation affects first the EUV and X-ray bands, then later the visible wavelength range.

The duration of night-time is calculated for the visible band, and in the peak of eclipse season (around mid-July [eclipsepeak])

!!Volume
Since moving to Hinode's S-band antenna for downlinks, the spacecraft typically can downlink something like 200 [Mb]


!!Do you have examples of what kind of observations are best suited for EIS?
Yes :-)


!!!Why can my old HOP no longer be run?
!!!How is the HOP process different?


Go over to the [Study4LowDataVolume] page on this Wiki for examples of programmes recently developed for EIS.

!!Nomenclature
;__OP__:[1|#1]''__Operation Programme''

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__Other Notes__

[2|#2]: Remember, Mb stands for mega__bits__, as distinct from MB (for mega__bytes__). 1 MB = 8Mb.

[3|#3]: Is this correct? I know it's approximately true, since we start in late April, and come out of eclipse season in early September.