Thread by @ChrisG_NSF

Good things come to those (modules) that wait. It's LAUNCH DAY for the #Nauka science lab! The long-delayed module finally gets its time to shine. Liftoff is set for 14:58:21 UTC / 10:58:21 EDT form Baikonur

Article from Katya Pavlushchenko (@katlinegrey)
nasaspaceflight.com/2021/07/nauka-…

With less than an hour to launch, let's take a trip through #Nauka's long history. There's a reason it's lovingly referred to as the "long suffering module."

A thread.... 1/x

#Nauka was originally a back-up to Zarya, in case that critical first ISS module was lost in a launch failure. Nauka, or FGB-2 as it was called then, was nearly complete when Zarya successfully launched in Nov. 1998. 2/x

So what to do with a nearly complete module? Surely not throw it away. Use it! And they did just that, deciding in 2004 to turn FGB-2 into a science module instead. Thus, the refit, and first launch date of 2007, began! 3/x

This is also when the European robotic arm was added to the module's design. @esa is on this flight, too! Nauka is an international collaboration. 4/x

Also, this is when it was named Nauka ("science"), technically Multifunctional laboratory module Nauka,” or MLM Nauka. The name would change again, but that's later. 5/x

Soon, delays began to appear. The launch slipped from 2007 to 2009 to 2012 to later. Then, in 2013, major defects were found, including metal shavings in the propellant lines. The module had to be fixed. 6/x

Fixing it oddly created a need to rename it, so it became "Multifunctional laboratory module Nauka, improved," or MLM-U Nauka. (That's a fun story. Read Katya's (@katlinegrey) article for full details: nasaspaceflight.com/2021/07/nauka-…). 7/x

After this, more issues were found and investigated, components of the now 20+ year old module were replaced... pushing launch to May 2021 and then to July 15 and finally today! July 21st! 8/x

For today's launch, #ProtonM will place #Nauka into a 190 x 350.1 km orbit at 51.6 degrees inclination. Nauka will then spend 8 days raising its orbit and undergoing systems checkouts while it -- in part -- waits for its docking port to become available. 9/x

That's because the #Pirs module is actually docked to where #Nauka needs to go. So if launch is successful today, Pirs will be undocked from the ISS by Progress MS-16 on Friday and destructively de-orbited, clearing the way for Nauka's arrival on July 29th. 10/10.