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Grant Tremblay Profile picture
@astrogrant
Apr 14, 2021 • 22 tweets • 10 min read • Read on X
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My favorite ground-based observatory is the Carruthers Observatory. ImageImageImage
The LMC. From the surface of the moon. Image
Every Carruthers Observatory image is also an album cover from a great indie band you've never heard of ImageImageImage
Anyway, @NASA should formally rename the observatory after George, who passed away in December. It still stands today by the foot of the LEM. Image
A visionary. nature.com/articles/d4158…
BTW, this bright streak is Ly-alpha. The Carruthers Observatory also did spectroscopy. And it took the first 'complete' UV images of the Earth's Geocorona. The haze you see around the earth is geocoronal Ly-alpha. ImageImage
The Finding Chart, for the Descartes Highlands on April 21, 1972 around ~noon EST, the time of the first EVA. The observatory was placed in the shadow of the LEM. Astronauts Charles Duke and John Young pointed the telescope by hand. Note the local geography on the horizon. Image
Exposure times were 3, 10, or 30 minutes. The telescope didn't track. The star tracks here is due to the rotation **of the MOON** w.r.t. the celestial sphere during a 30min exposure.

What's the field here?

The Galactic Center (Sagittarius). Image
The full Carruthers Observatory catalog is here: dropbox.com/s/pfb628ojl34t…
After the mission, Carruthers & Page wrote up the results from the observatory. You can read the paper starting at page 305 in the Apollo 16 Preliminary Science Report Image
They were supposed to get a 30 min exposure of NGC 1068, but the astronauts mis-pointed the telescope (understandable ... they had big gloves and ... well ... they were on the Moon). Image
whoops, I meant to link the PDF of the report! Page 305 here: hq.nasa.gov/alsj/a16/as16p…
Unfortunately, observatory is far too small to be resolved today, even by LRO. But it's there, standing in the shadow of the LEM. ImageImage
Highest resolution LRO image of landing site is here. Scroll and see if you can find it! wms.lroc.asu.edu/lroc/view_lroc…
The observatory is sitting in the hatched shaded area next to the LM. Credit for this overlay goes to: hq.nasa.gov/alsj/a16/a16Fl…
You can view all of the scanned Carruthers Observatory images here: archive.org/details/AS16-1…
I've also placed these scans for quick viewing on Dropbox here: dropbox.com/sh/t70o8i8rlnp…
Some cool little details, from the post-mission science report. hq.nasa.gov/alsj/a16/as16p… ImageImageImageImage
While the observatory itself is still on the moon, the actual film cartridge used is in @smithsonian's @airandspace collection. 😎 ImageImage
astrometry.net is absolutely incredible
by the way, there's a cool Astro 101 problem with this image, using the angular size of the star tracks and the fact that it's a 30 minute exposure
Unfortunately, in the Sagittarius images, the Galactic Center (Sgr A*) is *just* out of the field of view. Thanks to @AstroMikeMerri for thinking to use astrometry.net. Image

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More from @astrogrant

Grant Tremblay Profile picture
May 11
I remain pretty convinced that Apollo program Hasselblad photography remains a civilizational high water mark re: vibes / accidental art. And the lesser known ones are in some ways greater. Image
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or mostly it's just Walter Cunningham being effortlessly badass when looking out the window.
some of the most incredible and haunting and beautiful images of Earth are in Apollo 8 magazine 15F, the untouched/raw ones, and none of them are the famous ones everyone has seen. Image
Read 5 tweets
Grant Tremblay Profile picture
Feb 8
Some thoughts about @NASA I think remain true:

-Yes it's become a kludgeocracy, along w/ all of the Govt. This is ~25% NASA's fault & ~75% not its fault.

-A major reason why NASA is not fully @ fault is that it's really expensive to not be allowed to blow up taxpayer assets.
@NASA -Losing a satellite payload is a problem, losing a human being is a catastrophe. Flag-draped coffins will forever alter an organization's relationship to risk. This has, thank god, not yet happened for commercial space. It happened three times for NASA.
@NASA -One major and worsening problem @ NASA is that decision-making authority is diffused across an absurly labyrinthine org chart, and the organization operates on ultra-hard mode given a SUPER complicated dynamic w/ and between centers.
Read 27 tweets
Grant Tremblay Profile picture
Jun 20, 2024
I want to share the famous OMB memo on the future of NASA funding from '71 but let me preface it first: Image
NASA and NSF are in grave danger. Big science in the US may be totally screwed. Lots of vaporware, death spirals, evaporating teams and talent.

We face the looming age of austerity as the debt soars toward $50T, and servicing that debt now eclipses Defense spending... Image
Our biggest mandatory expenditures - medicare, medicaid, social security - are really boned - insolvent within a decade.

And amid rising geopolitical tensions, the Pentagon budget will soon race north of $1T with no end in sight. Image
Read 19 tweets
Grant Tremblay Profile picture
Aug 4, 2023
News for #AAS243 and beyond:

To protect our beloved, overworked meetings team, and because we only have ~2% active participation in a virtual component that costs >$200,000, we need to make major changes to how we do Hybrid. (1/n)

https://t.co/7h2rYbpS5Aaas.org/posts/news/202…
Image
In consultation with our friends on @AAS_WGAD and our Future of Meetings Task Force, we're asking for your thoughts on how we can more effectively incorporate virtual participants in our future meetings. We have many more details in this blog post:

https://t.co/RD635aHmAaaas.org/posts/news/202…
Image
@AAS_WGAD Here's the data for our past three hybrid meetings. The *majority* of Zoom rooms for the past three meetings have sat nearly or totally empty. Virtual presenters have unknowingly given talks to empty rooms. Glitches are frequent, even though we have a vendor-supported platform. Image
Read 17 tweets
Grant Tremblay Profile picture
Dec 17, 2022
We will build and fly a new constellation of Great Observatories, beginning with the Habitable Worlds Observatory. It will pursue life beyond earth, and with the power of a fleet including X-ray and FIR Great Observatories, we will tell the story of life in the Universe.
We can’t do this without a grassroots community coalition to advocate for the fleet at all fractal levels, from chats with a student to advocacy amongst stakeholders and policy makers. Join us here greatobservatories.org
Want to get involved now? We need you! Join NASA’s New Great Observatories Science Analysis Group by Jan 15. greatobservatories.org/sag
Read 4 tweets
Grant Tremblay Profile picture
Nov 15, 2022
Your AAS registration fee is very high. It's a huge barrier to participation. We're (quite literally) not allowed to bankrupt the society, but we can start a dialog about fees.

Hosting #AAS241 will cost us at least $1,612,249. We'll lose money or *barely* break even (1/n) Image
The largest expense by far is our collection of (excellent! professional!) A/V vendors, to whom we'll pay $424,000. Making the meeting hybrid effectively doubles their quote, i.e. adds about $200,000 to the total meeting cost. There is almost zero price competition in this space. Image
There is basically no compelling argument why a conference that costs you $700 in reg fee alone shouldn't provide you stable, fast wifi throughout the meeting. And so we will pay $147,000 to provide "free" WiFi throughout all venues. We have zero negotiating power here.
Read 13 tweets

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