In the top right of the video of a shuttle launch an astronaut has an open book resting on (attached to?) the left thigh. What was the purpose of this book? The astronaut then seems to take a pen or pencil with their right hand. How was pen/pencil secured for when they entered freefall? I'm assuming it was secured.
$\begingroup$ The astronaut in the left foreground also has one. $\endgroup$– Russell BorogoveNov 7, 2019 at 19:51
Those are the Ascent Checklist and the Ascent/Entry Systems Procedures (AESP) book. These are used by the back-seater Mission Specialists (MSs) and contain copies of the cue cards and flip-books used by the front-seater commander and pilot.
The MSs follow along in the checklists and back up the front seaters.
The Ascent Checklist contains the nominal and ascent abort procedures. The AESP contains malfunction procedures. Both are available at the JSC flight data file page: https://www.nasa.gov/centers/johnson/news/flightdatafiles/index.html
$\begingroup$ Is that a pen or pencil being used? Is it secured somehow? $\endgroup$– Bob516Nov 7, 2019 at 22:21
8$\begingroup$ Yes, it's a pen or pencil being used to check off steps and write in numbers. They could be tethered but weren't always. $\endgroup$ Nov 7, 2019 at 22:26
1$\begingroup$ @Bob516 it should be a pen, not a pencil, as a pencil can release conductive graphite powder into the atmosphere at 0g, and possibly short out things $\endgroup$ Nov 8, 2019 at 22:40
5$\begingroup$ @RichieFrame both pens and pencils are used in space space.stackexchange.com/q/36178/6944 $\endgroup$ Nov 9, 2019 at 2:37
1$\begingroup$ @uhoh the answers there are pretty much wrong. $\endgroup$ Nov 10, 2019 at 0:28