Space Stuff

 "He who is discontented with what he has, and what has been granted to him by fortune, is one who is ignorant of the art of living, but he who bears that in a noble spirit, and makes reasonable use of all that comes from it, deserves to be regarded as a good man." - Epictetus

Late on November 16th, just in case you were not paying attention, NASA launched a human-rated capsule that will orbit the moon and return home.  Artemis is the name of the program that intends to put humans back on the moon in a lunar base, and place a manned space station in orbit around the moon, which will be called "Gateway".  Gateway will act as a transfer station for earth traffic and also a docking point for lunar landers.  What an amazing time to be alive! 

This launch was considered somewhat risky from a technical standpoint, as this is the first full-scale flown test of the system - and they are going clear to the moon and back.  Godspeed, NASA.  

The Space Launch System, or SLS, is the main rocket assembly that was used to put the Orion Capsule and attached Interim Cryogenic Propulsion Stage (ICPS) into orbit.  The SLS main core is a couple of fuel tanks atop four Space Shuttle engines - tried and true technology, nothing new or untested.  Likewise the solid rocket boosters are the same thing used on the Space Shuttle, with an added section for additional burn length and thus payload capacity.

Once in orbit, the ICPS made a burn to make the orbit circular, then a second (18 minute) burn to send the Orion Capsule off to the moon, and then it detached itself.  The unmanned Orion capsule will arrive at the moon on Monday after a couple of course corrections, and place itself into a distant retrograde orbit (DRO) around the moon.  The DRO is an orbit that is highly stable, but also has the advantage of requiring less fuel consumption than the alternatives.  After a couple of weeks, it will perform another burn and send itself hurtling on an intersection path to where earth will be. 

I'm pretty confident that everything will work as hoped.  There are no docking or undocking maneuvers to perform, and nobody is on board who could be killed if the environmental systems fail.  Most of this stuff is old hat anyway, including the destination.  What is new, then?  Well the fact that we intend to go to the moon and maybe stay there!  This is the first step of that. 

There is an interactive Orion Capsule tracker at the NASA website (Screenshot Below)

 

The linked website shows the live values for capsule's speed and distance from earth and luna.  You can roll the image around, and major points of interest are white dots that you can click on.  They show milestones of the flight.  The blue line is the path of the Orion Capsule, and you can see where it will depart from the moon on the top of the screen - in a couple of weeks' time.  I believe it is supposed to return to earth on December 12.

Below is a diagram of the entire mission, courtesy of NASA, with mission milestones footnoted. 

 

The mission's main goals appear to be testing and validating everything before risking human lives with the equipment.  The only confounding issue is that this will be the fastest re-entry of a human-rated space capsule ever, and that is what everyone is wondering - how well will the heat shield hold up?  The $64,000 dollar question, as it were. 

Artemis II will be a crewed mission in 2024 that will perform essentially the same trip as Artemis I, except that it will carry four crew members on a 21 day journey.  This will make it the first manned flight to travel beyond low-earth orbit since Apollo 17 in 1972.  Very exciting.

Also exciting was the Leonid meteors I saw on the way home from work on November 17.  Meteors are best seen shortly before dawn, when that part of the earth you are standing on is heading in the direction of earth's orbit about the sun.  You get the most space dirt impacting the atmosphere at that moment.

Image courtesy of Bakersfield College.

I hadn't specifically gone out to look for Leonid meteors for decades, even though they make a wonderful display.  They are one of the fastest-moving meteor showers, moving at 45 miles/sec (72km/sec).  As a result, they burn up very quickly in the upper atmosphere - and I mean in milliseconds.  They often flash and light up the entire sky like lightning, and at first that's what I thought I was seeing on the drive home this morning just before dawn.  And I was thinking "It's way to freaking cold to have lightning.", but at that moment recalled that it was time for the Leonids.  I'd highly recommend setting a calendar appointment in your phone for 17 November 2023, and having a look at them next year.

Below is a video of some Leonids hitting the atmosphere and burning up, but it doesn't do them real justice.  They are quite startling, almost like a photo flash.

EDIT: I found a really cool old video about the complexity of landing a spacecraft in lunar orbit on earth.  There is an unbelievable amount of detail that needs to be calculated ahead of time, as well as some very narrow flight paths that need to happen.   Absolutely fascinating, even if the delivery is a bit dry.