Nostr notes by Mike Malaska

Uhm, gotta ask, but what is source of that image with the walking ...

2026-09-08T17:22:30Z

In reply to nevent1q…zs3k
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Uhm, gotta ask, but what is source of that image with the walking pole?
I did a ton of field work out at Vasquez Rocks. I love it immensely. (And posted pix publicly online, too.) Ad noticed that the pole in image looks exactly like mine!

Fun fact, although Vasquez Rocks is famous for beautiful sedimentary layers, if you go to the east end of the park (maybe 300 m from main parking lot) there are exposed weathered basalts and volcanics. Subtle, but definitely there.

.....and who was down beneath the squash foliage there munching ...

2026-08-29T20:35:02Z

In reply to nevent1q…zjh2
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.....and who was down beneath the squash foliage there munching on tomatoes? This guy.

A Sea of Squash. These squash vines got laughably large and took ...

2026-08-29T20:04:28Z

A Sea of Squash.

These squash vines got laughably large and took over most of the garden. They are butternut so should store fine. I'll deal with them (and the dry beans in there somewhere) when stuff dies back in later fall. I can see squash plopped down all over the place in there.

I think was only 2 x 20 row feet to begin with. They were not the "Bush" variety. Lesson learned!

We picked up 2.5 inches of rain last night. I wandered around the ...

2026-08-22T23:29:12Z

We picked up 2.5 inches of rain last night. I wandered around the property looking for cool mushooms.

Here is a Flaming Gold Bolete (Aureoboletus auriflammeus)

No. Its not AI. It is based on some SAR radar backscatter ...

2026-08-02T17:10:33Z

In reply to nevent1q…0kn0
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No. Its not AI. It is based on some SAR radar backscatter relationships. You can do it in a small area in certain cases in certain places. So the data it is based on exists. I'm just adding a factor and shift.

Hey Mastodon #science geeks, nerds, and boffins, I got a ...

2026-08-02T15:30:02Z

Hey Mastodon #science geeks, nerds, and boffins, I got a question.

I developing a way to generate a synthetic DEM. It is based on data, but not elevation data. It is tied to sparse elevation data.

It is definitely not "real" data, but it is not totally made up stuff either. Its semi-predictive.

So how would I describe this?
"Artists impression"?
"Artists impression based on sparse data"?
"Estimated rendering"?
"Pseudo-DEM"?
"Interpreted DEM"?

Any ideas? I don't want to oversell it.

This was....different. This is raw okra with soy sauce. This year ...

2026-07-27T00:00:19Z

This was....different.

This is raw okra with soy sauce. This year I tried growig Burmese Okra rather than the old standard of Crimson Spineless.

It has no spines and a lot less slime. Seed catalog said you could eat it raw so I did. This was a pretty long pod but still tender. I think I like it.

#gardening

Whoo-hoo! I can announce this now. I am now a CoI on a selected ...

2026-07-22T00:13:59Z

Whoo-hoo! I can announce this now. I am now a CoI on a selected NASA Advanced Innovative Concepts (NAIC) Phase I Study!!!

Titan is cool, right?
And flying on Titan is really cool, right?
And caves are cool too, right?

So, you may ask, what could be possibly cooler than flying inside a cave on Titan?

How about A MISSION CONCEPT TO FLY INSIDE A CAVE ON SATURN'S MOON TITAN WITH AN ELECTROHYDRODYNAMIC (= no moving parts) ENGINE?

I mean, srsly. FNA.

Link here: https://www.nasa.gov/directorates/stmd/niac/niac-studies/solid-state-propulsion-for-autonomous-reconnaissance-of-karst-spark/

Periodic table representation showing filling of successive ...

2026-06-03T17:10:12Z

In reply to nevent1q…v54p
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Periodic table representation showing filling of successive valence shells from center to right.

Filled shell is of noble gas, then spiraling counterclock-wise outward to the next fill level.

Poll time! Here is a quote from NASA Administrator Jared Isaacman ...

2026-04-11T20:25:32Z

Poll time!

Here is a quote from NASA Administrator Jared Isaacman (see: https://deepspace.social/@mike_malaska/116384128140587012):

“If we wake up and we see our rival’s taikonauts on the moon before we’re able to return, the blow to American exceptionalism will be so damaging, the shock wave will be felt around the world.”

If China beat the US to the Moon, how would you feel personally?

Came across this wide-view shot of flooded Badwater Basin in ...

2026-03-14T01:31:33Z

Came across this wide-view shot of flooded Badwater Basin in Death Valley National Park from March 2024. Click to embiggen and see the full view.

ahhh! Got some lit! ...

2026-02-19T19:13:35Z

In reply to nevent1q…vzdv
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ahhh! Got some lit!

https://www.sciencedirect.com/science/article/abs/pii/S0019103510004641

This is a pay-for article, but it seems that CO2 not happy on Iapetus. Won't trap for long.

What CO2 there is seems associated with low albedo stuff. (Not where youd expect from cold trapping)

So CO2 is either being generated from UV action of exposed organics/ice (in dark lag+UV produced superoxides from ice photolysis) or possibly-maybe CO2 got trapped up by associations. mineral/carbon stuff in dark lag material.

(I think the volatile moving around on Iapetus is still H2O, CO2 ...

2026-02-19T18:38:10Z

In reply to nevent1q…nlkf
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(I think the volatile moving around on Iapetus is still H2O, CO2 is trapped pretty everywhere, but slightly more in dark lag stuff.)

Like Iapetus, but free.

2026-02-19T18:31:09Z

In reply to nevent1q…l66n
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Like Iapetus, but free.

View from spheroidally weathered granite blocks in the Alabama ...

2026-02-11T23:51:47Z

View from spheroidally weathered granite blocks in the Alabama Hills National Scenic Area, California.

"Gosh, Mike, I bet running around in the desert you probably ...

2026-02-10T17:09:43Z

"Gosh, Mike, I bet running around in the desert you probably see a lot of wierd-looking plants, right?"

Oh yeah.

I present to you the Pagoda Buckwheat.

This stands only about 20 cm high.

It is very common along the roadside dropping into and climbing out of Panamint Valley on the road to Death Valley from Olancha, California.

Fine. I'll ditch the hashtag.

2026-02-02T05:30:48Z

In reply to nevent1q…xls2
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Fine. I'll ditch the hashtag.

Seriously? I can't post explanations?

2026-02-02T00:49:03Z

In reply to nevent1q…zs08
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Seriously? I can't post explanations?

The edge of a canebrake in snowy woods. Orange County, North ...

2026-02-01T21:27:05Z

The edge of a canebrake in snowy woods. Orange County, North Carolina.

#SilentSunday

(Wkipedia entry on Canebreaks. A moist lowland native bamboo thicket common in SE of North America: https://en.wikipedia.org/wiki/Canebrake)

Part 2: Tryptophan discovery: How do we know what we know? As ...

2025-12-12T21:23:15Z

Part 2: Tryptophan discovery: How do we know what we know?

As promised, we gonna circle back on that tryptophan discovery.
(For Part 1 in this series see here: https://deepspace.social/@mike_malaska/115653001232082594)

And this gets to an even bigger question in #astrobiology (and life in general):
“How do you know what you know?”

We gonna dive deep into the analytical chemistry of that reported tryptophan detection, digging into the supplementary information analysis.

[thread]

quoting
note1nz4…zjmv

Why is the potential discovery of tryptophan in an asteroid sample such a big deal for #astrobiology?

Gonna do a deep dive behind the headlines.

For starters, here is a link to the discovery article: https://www.pnas.org/doi/10.1073/pnas.2512461122

thread time!

Why is the potential discovery of tryptophan in an asteroid ...

2025-12-03T01:19:10Z

Why is the potential discovery of tryptophan in an asteroid sample such a big deal for #astrobiology?

Gonna do a deep dive behind the headlines.

For starters, here is a link to the discovery article: https://www.pnas.org/doi/10.1073/pnas.2512461122

thread time!

Freeze expected tomorrow. I pulled the okra and put it by compost ...

2025-11-09T18:53:30Z

Freeze expected tomorrow. I pulled the okra and put it by compost bin to chop later.

Despite being late season, yanled out of the ground, and thrown in a pile awaiting a killing freeze, it is still trying!

That's the spirit!

Be like the okra.

My Incedible Superpower is spotting useful seedlings at the three ...

2025-11-02T19:24:27Z

My Incedible Superpower is spotting useful seedlings at the three or four-leaf stage.

I'm a lazy gardner. I just let open pollinated stuff go to seed, sprout wherever, then spot and carefully transplant later.

Here is an example bed I let idle. Over a year ago I had lettuce in here. There are a bunch of weeds, but one little lettuce seedling.

Can you find it?

#gardening

Please RT. This link will help find the nearest foodbank in the ...

2025-10-29T23:07:18Z

Please RT. This link will help find the nearest foodbank in the United States. There is a search bar by zip code that provides a list of food pantries nearby.

https://www.feedingamerica.org/find-your-local-foodbank

By combining gases, adding some metal vapor, and using colored ...

2025-09-27T03:52:00Z

In reply to nevent1q…3xa2
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By combining gases, adding some metal vapor, and using colored glass and blowing multiple tubes with different effects you can make some interesting signs.

Like the neon sign for Dr. Kilzum pest control services. A lot of different colors and shapes on this 10 foot tall sign. Imagine blowing all those glass tubes!

"Neon" is a generic term for sticking rarified noble ...

2025-09-27T03:33:17Z

In reply to nevent1q…m87z
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"Neon" is a generic term for sticking rarified noble gases (and maybe some metal vapor) in a tube and zapping it with high voltage alternating current.

The high voltage strips off the outermost electron, and when it pops back in, it releases a photon at the corresponding quantum level.

You get the same effect in an aurora. But noble gases are not corrosive.

Here is a transparent display that show the different noble gases.

Yes. That previous piece is a neon art representation of the ...

2025-09-27T03:24:19Z

In reply to nevent1q…0efv
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Yes. That previous piece is a neon art representation of the freeway system around downtown Los Angeles!

Here is another very abstract large piece that was next to the LA nein piece. It was pretty big, maybe 2m on a side.

Today I went to the Neon Museum of Modern Art in Glendale, CA. ...

2025-09-27T03:15:59Z

Today I went to the Neon Museum of Modern Art in Glendale, CA. Very fun!

Small, niche, and kitsch.

They had lots of neat glowy stuff. I took many pix. For the ones that flash, I'll post a CW.

The museum also has a workshop and for bigger bucks you can take a class to learn how to be a "neon bender".

(Anyone want to guess what this abstract neon piece represents? Answer in next post.)

[Thread]

The NISAR mission's radar antenna has fully unfurled! ...

2025-08-16T00:33:18Z

The NISAR mission's radar antenna has fully unfurled! Whoo-hoo!

https://www.jpl.nasa.gov/news/giant-radar-antenna-reflector-on-nasa-isro-satellite-in-full-bloom/

Sunset on the Salish Sea. Lighthouse in Mukilteo, Washinton at ...

2025-07-22T06:06:03Z

Sunset on the Salish Sea.

Lighthouse in Mukilteo, Washinton at sunset.

Floating in Kraken Mare and looking for life has its own issues. ...

2025-04-26T15:47:01Z

In reply to nevent1q…x3sx
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Floating in Kraken Mare and looking for life has its own issues.

What would you look for? You'd filter out any solids prior to analyzing the liquid so you dont gunk stuff up. Back to only looking at a handful of soluble molecules (srsly. I prepared this list for the Oceanus Calypso probe. These are not exciting molecules.)

At low T, you'd want to look for molecular associations. Need in situ NMR, not destructive GC.

I'm a very wet blanket regarding methane-based life.

Imma push back on this way hard. Cryogenic methane is a truly ...

2025-04-26T15:26:42Z

In reply to nevent1q…qu53
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Imma push back on this way hard.

Cryogenic methane is a truly lousy solvent. There is a VERY short list of organic molecules that will dissolve in it and let you shuttle energy-carrying molecules from one place to another.

I challenge anyone to build up a biochemical cascade using ONLY cyclopropane and butane.

(And I'm not even mentioning synthesis of A+B-->AB where AB is so insoluble it gloms itself to the enzyme active site - catalytic turnover of one.)

The other recurring theme is that we need to improve planetary ...

2025-04-26T13:56:48Z

In reply to nevent1q…s7cj
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The other recurring theme is that we need to improve planetary instrumentation and lower the detection limit.

1E3 cells per cm3 is just not good enough. We need to push to much lower.

This will also help us explore Earth and can also help with medical technologies (just how "sterile" is that water, anyway?)

So this article also serves as a call for better instrumentation for planetary #astrobiology.

There will be more on that in a few weeks. (Stay tuned)

\end thread.

But the really big news (that got missed in the hype) is that ...

2025-04-26T13:53:38Z

In reply to nevent1q…302p
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But the really big news (that got missed in the hype) is that TITAN IS HABITABLE.

Our numbers show that it could support at least a small dog worth of biomass.

(If you found a small dog on Titan you'd be pretty happy, right?)

So the numbers, while low, will likely only go up as we get better data (more metabolisms) and better ideas of where to look.

In micropockets, you can get concentration effects of about 1E6 ...

2025-04-26T13:50:34Z

In reply to nevent1q…4llz
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In micropockets, you can get concentration effects of about 1E6 as ice grains squeeze out non-water molecules. So you could get a hyperlocalized concentration.

Which could push an effective cell count to 1E3 cells per cm3 which is now in range of current state-of-the art instrumentation.

There are other ways to localize biomass too. Happens all the time here on Earth.

Another thing is where are all those cells. Are they gonna be ...

2025-04-26T13:46:38Z

In reply to nevent1q…7u4l
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Another thing is where are all those cells. Are they gonna be swimming around in the dilute-ass ocean?

(Y'all should know I think the ocean of ocean worlds is the WORST place to look for life. Big. Dilute. Boring.)

Life loves interfaces. Ice-ocean interface, ice-bottom interface, brinicles, cold-seeps (up or down), and especially micropockets in ice.

(I'll be posting something exciting about micropockets in a few weeks. Stay tuned.)

An analogy is that 1 person can live on 1 frozen pizza a day. So ...

2025-04-26T13:42:28Z

In reply to nevent1q…r2cp
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An analogy is that 1 person can live on 1 frozen pizza a day. So if you go into a grocery store and just count number of frozen pizzas, then that gives you an estimate of how many people that grocery store can feed, right?

(Wrong. there are also frozen Turkey Pot Pies. Maybe other things, too. :) )

We only considered glycine fermentation. There are lots of other ...

2025-04-26T13:39:18Z

In reply to nevent1q…de7s
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We only considered glycine fermentation.

There are lots of other molecules that could be yummy microbe food (naphthalene is my favorite). But we only had really really good numbers for terrestrial microbes for glycine at low temperatures and high pressures. So that's a data issue.

(The article is a call-out for low T, high P, microbiology experiments for funky metabolisms).

If you dilute that out over the whole subsurface ocean, it give ...

2025-04-26T13:36:21Z

In reply to nevent1q…xt69
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If you dilute that out over the whole subsurface ocean, it give you numbers around 0.001 cells per cm3 (1E-3 cells per cm3) - that is one hundred time LOWER than medically sterile.

That's bad news for Titan #astrobiology right?

Well, not really.

Here's why:

In the Titan habitability calculation, we estimated the total ...

2025-04-26T13:32:53Z

In reply to nevent1q…26l3
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In the Titan habitability calculation, we estimated the total amount of cell mass that could be supported by glycine fermentation based on the estimate glycine delivery from the top surface all the way through 100 km of ice into the deep subsurface ocean of Titan.

And we came up with a small dog's worth of cell mass.

Affholder et al. 2025 (open-access article): https://iopscience.iop.org/article/10.3847/PSJ/adbc66

Here are some numbers for comparison, in microbes per cm3 volume: ...

2025-04-26T13:29:30Z

In reply to nevent1q…l7qf
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Here are some numbers for comparison, in microbes per cm3 volume:

Theoretical maximum limit: 1E15 cells per cm3
{this is based on the theoretical lower limit for microbial cells}
Human body: about 2E8 cells per cm3
Deep Ice (2.5 km deep in Greenland ice sheet): 1E5-1E4 cells per cm3
Instrument detection limit: 1E2 cells per cm3
Medically sterile: 0.1 cells per cm3

"Habitability" is one of the most misused words in ...

2025-04-26T13:27:17Z

In reply to nevent1q…srd4
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"Habitability" is one of the most misused words in astrobiology. It is a usually a blurry concept used to justify a mission: “The [insert mission name here] will investigate the habitability of [insert world name here]”.

More recently, habitability is becoming an actual quantitative and comparative concept. Specifically, how many microbes can exist in an environment?

Here is an open-access article on Planetary Habitability:
Mendez et al, Astrobiology 2021: https://www.liebertpub.com/doi/10.1089/ast.2020.2342

#astrobiology thread time! A paper came out a few weeks ago about ...

2025-04-26T13:06:14Z

#astrobiology thread time!

A paper came out a few weeks ago about "habitability". Specifically, the habitability of Saturn's moon Titan.

We (am one of the co-authors) found that Titan's chemistry could support the equivalent biomass of a small dog.

Is that....bad?
(And what does "habitability" mean anyway?)

Here is the press release from the University of Arizona: https://news.arizona.edu/news/saturns-moon-titan-could-harbor-life-only-tiny-amount-study-finds

(Next post will have link to full paper)

A symmetrical scene on a #SilentSunday on the shore of the Salish ...

2025-04-07T03:09:18Z

A symmetrical scene on a #SilentSunday on the shore of the Salish Sea.

Mukilteo, Snohomish County, Washington State

As the Huygens probe descended, it took lots of pictures on its ...

2025-01-15T13:52:32Z

In reply to nevent1q…n2pq
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As the Huygens probe descended, it took lots of pictures on its way down to the surface. Those are just a gold mine of information.

Here is a really fun movie that we call the "bells and whistles" version. It is incredibly information rich. I love watching this over and over. You can see little cartoons showing probe orientation spin, telemetry data, instrument sequences, and images. I love to marvel at the planning that made this happen.

https://science.nasa.gov/resource/titan-descent-data-movie-with-bells-and-whistles/

Ahhhhh. That's still a mystery! You will read in Wikpedia or ...

2025-01-15T13:45:34Z

In reply to nevent1q…k63z
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Ahhhhh. That's still a mystery! You will read in Wikpedia or some of the literature that it is water ice.

But actually, we don't know. It could be ice, or other things: frozen benzene, solid HCN, mixed solid organics. We do not have detailed spectra or other chemical analysis of those rocks vs the sands.

(Personally, I think it's probably ice, but I want better proof.)

(The dark sands I'd lean my guess towards probably organics.)

It is good to have mysteries! Fun! Explore!

So. Streams or floods, rocks eroding, sorting. Faster than ...

2025-01-15T13:44:26Z

In reply to nevent1q…jrp9
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So. Streams or floods, rocks eroding, sorting. Faster than getting covered by atmospheric organic molecules. Got it.

But what are those rounded rocks made of?

And also what you DON'T SEE. We don't see a uniform ...

2025-01-15T13:39:27Z

In reply to nevent1q…nsjv
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And also what you DON'T SEE. We don't see a uniform snowscape blanket of organic molecules everywhere.

That tells us that whatever geological processes happen are faster than covering by organic molecule fallout.

That fallout happens at a rate of about same as dust builds up in your house if you have a clothes dryer in your house. Max 100 m per Gyr: 0.1 m per Myr, 0.1 mm per kyr or 0.1 microns per year. Give or take an order of magnitude.

So geology happens on Titan. It's not boring.

Just from this surface image, you can figure stuff out. All those ...

2025-01-15T13:34:40Z

In reply to nevent1q…rmd0
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Just from this surface image, you can figure stuff out. All those rocks (whatever they are made of - that is still a mystery), are all rounded, and the same size.

Rounding suggests erosion, those "rocks" banged together repeatedly. Likes rocks in a river or shore (hint-hint-hint).

And sorting by some type of process where bigger rocks dropped out somewhere else, and smaller rocks or pieces dropped somewhere else.

Either a flood deposit or a stream deposit.

On January 14, 2005 just over 20 years ago today, the Huygens ...

2025-01-15T13:28:26Z

On January 14, 2005 just over 20 years ago today, the Huygens probe touched down on the organic-rich surface of Saturn's moon Titan.

Here is the scene from Titan's surface. https://photojournal.jpl.nasa.gov/catalog/PIA07232

Scientists (I'm one of those) have been analyzing this image and the other descent images from the probe for 2 decades. What have we learned from the probe images about the surface of enigmatic moon?

[Thread]

For example, if someone found a single-dose cure for ...

2025-01-05T21:41:24Z

In reply to nevent1q…fwvt
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For example, if someone found a single-dose cure for Alzheimer's they could probably name their price.

Market would easily support $100k per person in my guesstimation.

In US, there are 500,000 new cases of AD per year. So that is a whopping $50B potential market.

I can't see the public sector allocating that much even if it was only just to break even economically.

(Current public funding only about 10% of that and doesn't have that goal.)

Would agree sorta. Some of these issues are baked into the ...

2025-01-05T21:27:29Z

In reply to nevent1q…m35c
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Would agree sorta. Some of these issues are baked into the system.

However, antibiotics, antifungals, and antiparasitics do produce cures. Nobody would buy a bacterial-stat when a bacterial-cide was available.

Same with other drugs. All things equal, a cure for cancer or Alzheimer's or whatever would always outcompete a long-term treatment for same disease.

In this case the competitiveness works for you to incentivise better treatments.

Costs for clinical trials should be the same for either private ...

2025-01-05T19:56:32Z

In reply to nevent1q…gjjw
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Costs for clinical trials should be the same for either private or public sector.

I honestly don't know what drives clinical costs. I've always assumed it is the personnell costs of record-keeping, administration developing protocols, dealing with Investigational Revew Boards, etc.

(I also dont have a good handle on R&D costs spent vs. drugs approved for public sector efforts. Any ideas?)

Sorry. I wasnt super-clear in explanation. Was assuming a total ...

2025-01-05T19:49:26Z

In reply to nevent1q…jefe
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Sorry. I wasnt super-clear in explanation.

Was assuming a total market potential of $1B per year, but assumed the successful drug would only capture 50% of that market averaged over 16 years.

So $500M per year actual sales over 16 years gives $8B total which is just enough to cover costs. No profit.

Means you need $1B per year potential to even think about a program.

(Which, as you stated, economocally limits targets.)

...the other implication is that you gotta make up for that ...

2025-01-05T17:31:42Z

In reply to nevent1q…l556
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...the other implication is that you gotta make up for that initial cash outlay on the back end.

So assume 16 years of exclusive patent period and average during that period of 50% market penetration you need to have a $1B per year drug to make up for your initial costs.

Big question: Is there a $1B per year driving need RIGHT NOW for a new antibiotic?

(Remember, there are other generic antibiotics, insurance companies will want to try those first.)

So, if you want new antibiotics, someone's gotta: 1) pony up ...

2025-01-05T17:27:33Z

In reply to nevent1q…74c6
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So, if you want new antibiotics, someone's gotta:

1) pony up a several BILLION dollars of dedicated R&D effort for just this.

2) find some way to improve that 96% failure rate.

That 96% is ingrained in every pharma scientists brain. Keeps us humble. There is always a "bold new paradigm to accelerate drug discovery" that never moves the needle.

Other clues are that a few different pieces get assembled up into ...

2024-10-15T01:55:39Z

In reply to nevent1q…yy9k
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Other clues are that a few different pieces get assembled up into bigger things. When amino acids get assembled up they become proteins and enzymes. Assembled up, nucleotide bases become DNA and RNA.

Some small structures (CH2CH2) and isoprenyl get built up into membrane molecules. (I like membrane molecules.)

When you smack them with an MS. You see these repeating breakdown chunks as the links sometimes fall apart because the links and connectors are weaker.

One clue, is that there are many many possible structural isomers ...

2024-10-15T01:50:58Z

In reply to nevent1q…va4e
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One clue, is that there are many many possible structural isomers for a molecule of a given size. Abiotic chemistry makes a (sorta) random mess.

In contrast, biology uses molecular things. So you might see a few key molecules, but lots of them. Lower diversity.

As an example, go into a forest after a windstorm, wood of all sorts of lengths lying everywhere. But go into a lumberyard, and sizes and lengths are pretty standard: 8ft, and 12 ft.

Standardized stuff makes building things easier.

Heya #mapstodon , Has anyone used StoryMap JS? Reccomend? Any ...

2024-08-31T15:24:11Z

Heya #mapstodon ,

Has anyone used StoryMap JS?

Reccomend? Any good tutorials or tips?