All Photos & Illustrations Credit: NASA unless noted otherwise.
26 November 2015
I think the previous post about the James Web Space Telescope (JWST) was a worthwhile detour from The Journey to Mars, and here we are back on track, so let’s continue the journey . . .
The photo, below, shows NASA employees at Kennedy Space Center in Florida viewing the Orion Multi Purpose Crew Vehicle (MPCV) with the Heat Shield and Back Shell removed. The pristine condition suggests that Exploration Flight Test-1 (EFT-1) was a success (which, indeed, it was).
The photo, below, shows the heat shield returned to the lab for inspection after EFT-1.
It has been almost a year since Orion successfully completed the Exploration Flight Test-1 in early December 2014. The NASA Orion Engineering Team has been developing improvements for the Heat Shield based upon data collected from the many pressure and temperature sensors on Orion during EFT-1.
The photo, below, shows the heat shield being inspected before it was attached to Orion during assembly, BEFORE the test . . .
The titanium framework visible in the photo provides strength and rigidity. The good news is that the data collected during flight and reentry will allow the framework to be “tweaked” so that it will weigh less and cost less. Notice the smooth orange color on the body of the shield – that is the Avcoat ablative material that carries heat away from Orion during reentry into the atmosphere. While the ablative material did meet the objectives for EFT-1, there were concerns following the detailed investigation after the test that the monolithic coating of ablative material would not suffice for future, more demanding flight and reentry conditions.
In any event, the engineering team decided to change the physical characteristics by using individual Avcoat filled honeycombed tiles instead of the monolithic coating used for EFT-1.
The photo, above, shows some tiles attached to the heat shield that will be used for the next test, Exploration Mission Test-1 (EMT-1). EMT-1 will keep Orion in cislunar space for almost a month and the reentry speed will be about 36,000 feet per second (about 6,000 feet per second faster than EFT-1) and temperature increases exponentially with increased speed.
This “Design/Build/Test/Improve, then Test again” approach that is being used for the Orion Heat Shield is typical for everything that NASA does. Space travel is a very dangerous business and PERFECTION must be the goal. “Good enough” simply isn’t. “Too much” is just about right when it comes to safety and performance for space travel.
Having said all that, it is time to take a closer look at the Orion Service Module that provides propulsion, electricity, water, and air for the Orion Multi Purpose Crew Vehicle (MPCV) . . .
The service module illustrated above is expendable and does not return to Earth with the Crew module.
The Service Module solar panels provide electrical power for the Orion spacecraft when it is operating independently from the SLS rocket structure.
I don’t know whether the circular or rectangular solar panels will be used for the circumlunar test, which is planned for about two years hence.
The illustration, below, shows a Service Module with rectangular solar panels.
That’s it, for now. The next post is not quite ready for prime time yet, but I hope to have it finished soon.
Meanwhile, keep looking up, there’s lots to see up there on clear nights. Heck, you can even see the Space Station with the naked eye, if you know where (and when) to look. How do you find out where and when to look ?? Easy – – just get daily email from NASA that tells you all about it. Check it out at: