Good morning/afternoon Steemit!   After Friday's successful launch and deployment of BulgariaSat-1, SpaceX is preparing again to launch and land a Falcon 9.  

Today from their launch site at the Vandenberg Air Force Base in California they will be launching 10 additional satellites as part of Iridium's NEXT satellite constellation (Friday's launch incorporated the first stage used to launch the first segment of this constellation back in January).  They will subsequently land on their west coast drone ship, "Just Read the Instructions".

<a data-flickr-embed="true"  href="https://www.flickr.com/photos/spacex/35496028185/" title="BulgariaSat-1 Mission"><img src="https://c1.staticflickr.com/5/4216/35496028185_1e79498d7c_k.jpg" width="2048" height="1365" alt="BulgariaSat-1 Mission"></a>

Aside from the historic turnaround time that will be established if today's launch doesn't scrub (2 days!), one new thing that will be introduced with today's launch are the addition of titanium grid fins on the Falcon 9 rocket.

<center>![DDHips8VwAAS_4i.jpg](https://steemitimages.com/DQmVgBM8rZaY6BQyNV7HU1vxHYEJsSPZs3a7S4MRXfrRe4A/DDHips8VwAAS_4i.jpg)</center>
*Image from SpaceX Twitter, note the dark grey fins just below/adjacent to the American flag*

This will improve control authority allowing for higher angle of attack on re-entry while also improving reusability as it will not require additional ablative shielding such as that utilized on the current/previous variation of the Falcon 9 rocket's aluminum grid fins.  This is a step towards the "final" planned version of the Falcon 9 rocket, Falcon 9 Block 5, which will also feature increased thrust and other changes to optimize reusability of the first stage.  See below video of the aluminum grid fins glowing on re-entry:

<center>https://www.youtube.com/watch?v=NDN36VdT2WQ</center>

*Video clip from SES-10 launch webcast*

Today's launch window is instantaneous and opens at 20:25 UTC (4:25 EDT).  Plan to tune in below 15-30 minutes prior to the launch to watch the hosted webcast including countdown/pre-flight checks of the rocket.  If today's launch scrubs, the next opportunity is set for 20:19 UTC tomorrow (Monday, June 26th).

<center>https://www.youtube.com/watch?v=7tIwZg8F9b8</center>

Feel free to drop any questions or commentary below and I'll do my best to follow up.  
Hope you've enjoyed the post!

![echozsigv2.png](https://steemitimages.com/DQmPqQdExSxqhp7p1y3FbyPDusWniAq3sUULWUMVY1mg3UD/echozsigv2.png)