TODAYS NASA UPDATE JULY 26

Message: 1

From: NASA News Services
Date: Fri, 24 Jul 2009 05:02:00 -0500 (CDT)
Subject: Battery Work During Fourth Spacewalk

Battery Work During Fourth Spacewalk
Fri, 24 Jul 2009 04:37:40 -0500

The joint crew of Endeavour and the station was awakened at 5:03 a.m. EDT by Pink Floyd’s “Wish You Were Here,” played for lead spacewalker Dave Wolf.

Spacewalkers Chris Cassidy and Tom Marshburn will head outside at 9:58 a.m. to swap out all four of the remaining P6 truss batteries, a task that is expected to take about seven and a half hours. Two of the six original P6 batteries were changed out during the mission’s third spacewalk on Wednesday, but work was stopped when carbon dioxide levels in Cassidy’s suit began to rise, unexpectedly.

Message: 2

From: NASA News Services
Date: Fri, 24 Jul 2009 08:03:46 -0500 (CDT)
Subject: Giants Among Us



Giants Among Us
Thu, 23 Jul 2009 23:00:00 -0500


Apollo 11 astronauts, from left, Michael Collins, Neil Armstrong and Buzz Aldrin stand in recognition of astronaut John Glenn during the U.S House of...

Message: 3

From: NASA News Services
Date: Fri, 24 Jul 2009 09:01:03 -0500 (CDT)
Subject: Fourth Spacewalk Begins at 9:54 a.m. EDT

Fourth Spacewalk Begins at 9:54 a.m. EDT
Fri, 24 Jul 2009 08:59:05 -0500

Spacewalkers Chris Cassidy and Tom Marshburn began the STS-127 mission’s fourth spacewalk at 9:54 a.m. EDT when they switched their spacesuits to battery power.

They will replace four of the remaining Port 6 truss batteries in a planned seven and a half hour spacewalk. Two of the six original P6 batteries were changed out during the mission’s third spacewalk on Wednesday before work was cut short because of anomalous carbon dioxide levels in Cassidy’s suit. The lithium hydroxide canister that scrubs CO2 from the suit was replaced for today’s spacewalk.

The new batteries are stored on the Integrated Cargo Carrier – Vertical Light Deployable, or ICC-VLD positioned near the Port 6 truss. Cassidy and Marshburn will work together to remove insulation from the old Port 6 batteries, install scoops to gently remove them, pass the batteries back and forth to a stowage location on the ICC-VLD, and repeat the process to replace them with the new batteries.

Each new battery assembly consists of 38 lightweight Nickel Hydrogen cells and associated electrical and mechanical equipment. Two battery assemblies connected in series are capable of storing a total of 8 kW of electrical power. This power is fed to the space station via the Battery Charge/Discharge Unit and Direct Current Switching Unit respectively. The batteries have a design life of 6.5 years and can exceed 38,000 charge/discharge cycles at 35% depth of discharge. Each battery measures 40” by 36” by 18” and weighs 375 pounds.

Message: 4

From: NASA News Services
Date: Fri, 24 Jul 2009 11:00:45 -0500 (CDT)
Subject: First Battery Replaced

First Battery Replaced
Fri, 24 Jul 2009 10:32:56 -0500

At 11:17 a.m. EDT, STS-127 Mission Specialists Chris Cassidy and Tom Marshburn replaced the first of four batteries they plan to exchange during today’s spacewalk. They just completed releasing the fourth old battery from its location on the space station’s Port 6 truss.



An hour and 35 minutes into the spacewalk, they are on the planned timeline and their spacesuit consumable levels are normal.