General Discussion

[b]Day 6: 15 January 2018[/b] @VincentAnderlin @kallimabutterfly @NotarySojac @Firra @BezimiennyRaptor @Cunea [img]https://cdn.discordapp.com/attachments/312830597901058048/402611828158627871/planck_in_large_space_simulator_testing.jpg[/img] Planck, the ESA's CMB mapping satellite, awaiting testing in a launch simulation room. CMB observation is probably my nerdiest sub-interest when it comes to spacecraft. The CMB (Cosmic Microwave Background) is essentially energy left over from the Big Bang. When it was discovered back in the 60's, it was a big deal, because it was some of the first physical evidence supporting the Big Bang theory. In the 80's, NASA put up a satellite called the COsmic Background Explorer (COBE) to map the CMB and discovered a lot about the early universe, even from COBE's blurry images. COBE led to the development of newer CMB observation instruments. The first was WMAP, launched in 2001. Planck came later, in 2009, and mapped the CMB to an accuracy still unsurpassed by any other observatory, spaceborne or not (though I can't imagine you can see much of the CMB from Earth; both WMAP and Planck were placed at Lagrange point 2 so as to avoid interference from Earth and the Sun.)

this thread makes me happy

Oooh, today's picture and explanation was so interesting!

I am really loving all of these posts, and learning all sorts of new things about spaceflight!
Thanks violalore :)
(PS: do you like legos? I'm currently working on the Saturn V model and I really recommend it since you're a fan of spaceflight)

@Cunea oh my god I got the Saturn V and built it all on Christmas instead of talking to people. Never underestimate a determined nerd who's avoiding family!

@Firra glad you're enjoying it! :)

@kallimabutterfly me too :0

Day 7: 16 January 2018 @VincentAnderlin @kallimabutterfly @NotarySojac @Firra @BezimiennyRaptor @Cunea [img]https://cdn.discordapp.com/attachments/276515100465299456/402917162760536076/unknown.png[/img] I knew I would post this eventually. I've been trying to put it off, but... eh. Today's image is gonna take a little explanation. This is the battery onboard the satellite WMAP, taken during processing. About 7 years into WMAP's 9 years of operation, the battery output suddenly fell. This led NASA to develop a Problem Resolution Team, or PRT, to figure out what was going on, ultimately aiming to make sure battery output wouldn't get in the way of observation. (If you remember from yesterday, WMAP, the Wilkinson Microwave Anisotropy Probe, was one of three CMB observation satellites. Some more context: WMAP observed the CMB from 2001-2010. At the time of its first observations, WMAP's accuracy was absolutely unprecedented, and the information it gave physical cosmologists about the CMB was a key factor in developing their current model of cosmology. I'm not an expert in images -> age of the universe--it's not rocket science, after all--but I know that Stephen Hawking saying "WMAP's evidence for inflation was the most exciting development in physics during his career" is no easy feat for a satellite to achieve. [ [url=https://map.gsfc.nasa.gov/]source[/url] ]) You can imagine that its battery suddenly dropping in output is a big deal for such an important satellite. So, what did the PRT decide? They started by making a list of possible culprits for the satellite, including manufacturing defects, foreign object debris (FOD), external short circuits, battery overcharge, depleted capacity due to age (i.e. getting old), undercharge, and electrolyte bridging within the battery. Most of these were ruled out pretty early; why would FOD only cause a problem seven years into operation, and only in a few specific cells of the battery? The only things that could be problems were undercharge and electrolyte bridging. I'm gonna stop here because I'm not an electrical engineer, and I'm not confident in my ability to teach the specifics of this issue effectively, but if you're interested, it pops up on pages 32-33 of today's source. So there you go: a satellite battery. I hope that's as cool to you guys as it is to me! This image was accessed from the WMAP Battery Operations PRT's report [url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100030608.pdf]here[/url]. The image appears on page 21 of the report.

[b]Day 8: 17 January 2018[/b] @VincentAnderlin @kallimabutterfly @NotarySojac @Firra @BezimiennyRaptor @Cunea [center][img]https://cdn.discordapp.com/attachments/276515100465299456/403288446497587201/nasaartprogram_thon.png[/img][/center] In searching for the artist of a painting of John Young, I found an article filled with beautiful artworks about NASA spaceflight history. Picking just one for today was really difficult; I was tempted to pick the painting of John, but I ended up swaying away from it for the time being. This watercolor painting, by William Thon, is titled [i]Space Age Landscape[/i]. The caption of it in the article summarizes it better than I can: [indent][i]The subtropical climate of Florida soon reclaims an early launch tower. As the space program progressed to larger launch vehicles, smaller gantries were abandoned to seabirds, who found them to be ideal nesting places.[/i][/indent] I picked this image for a couple of reasons. The first is just the aesthetic of it; I'm a sucker for subtler color palettes and less saturated images. But the main reason I picked it is because I think it's a really poignant reminder that ultimately, spaceflight is a contest, driven by us, against the pull of Earth. I think this image captures really well the complex relation between us humans as inventors and the Earth who nurtured us from our conception. It's tempting, especially for us enthusiasts, to view our expansion throughout space as a slow but linear process, and to associate spaceflight with progress... but ultimately, I think we'll always end up returning home, even if we send others right outside the door again. :) I'd love to hear your thoughts about the image, too, though. This image was accessed from Maria Popova's article [url=https://www.brainpickings.org/2013/08/29/nasa-art-program/][i]The Art of NASA: Andy Warhol, Annie Leibovitz, Norman Rockwell, and Other Icons Celebrate 50 Years of Space Exploration[/i][/url].

@violalore this is the best thread <3 can I be added to the pinglist please?

@Kirmon64 of course :)

[b]Day 9: 18 January 2018[/b] @VincentAnderlin @kallimabutterfly @NotarySojac @Firra @BezimiennyRaptor @Cunea @Kirmon64 [center][img]https://78.media.tumblr.com/73f1bbf3cbc51f67405a2e1338ded385/tumblr_nialliWTPc1qigaa4o1_540.jpg[/img][/center] As proof that I will literally never shut up about Apollo 13, today's picture is of Jim Lovell training for his lunar landing in the highlands around the Fra Mauro crater. Spot the irony? Yeah, this is my new favorite example of dramatic irony: when we as an audience know something that the characters (or, in this case, the astronaut) doesn't. Like the fact that he's working his rear end off training for a landing that will never happen. Anyways. I do know that the equipment he's holding there is a hand tool carrier (HTC). From perusing the [url=https://www.lpi.usra.edu/lunar/ALSEP/pdf/ALSEP%20%2384%20-%20Apollo%20Hand%20Tool%20Carrier.pdf]manual[/url] and looking at images of the astronauts with the HTC in training, I'm just gonna vaguely say that it's for geology, since unfortunately I don't know much about the specifics of that particular subject yet. I'm not sure who the guy on the right is, but if anyone knows, I'd love to find out!