Drive by science

[JoeP]

That's p cool.

[Ari]

This is cool, although it could be sped up even more.

Rotting Fruit on Scale - YouTube

Up until around day 145 the weight loss is water based, and I presume that if the room were drier it would dehydrate instead of rot. However enough water has collected at the point of contact with the glass to sporulate some green mold.

From there on you can see how mold and fungi eat. There’s a spreading brown area that’s created by the mold releasing digestive enzymes that break the plant cells up into a nice wet slurry to grow into. Molds have an array of enzymes and chemicals in their genetic bank and choose what to produce depending on what they face. Penicillin for example was only discovered because the mold was under threat by bacteria. In this way molds that might make someone sick to their stomach in one environment might also make tasty foodstuffs in others.

The white leading edge is the mold mycelium that produces these enzymes and replicates, the cells that are left behind then mature and bud to form spores. The green following are mature spores. What you can’t see well here is that the spores transition from clear to colored as they mature, once green they are ready to spread and become quite dusty if disturbed. The spores are hydrophobic and will rise with moistuire while resisting becoming saturated, or as anyone who has ever done it once will tell you, using a misting spray bottle to coat this green with water/alcohol is going to get a face full of spores.

The weight loss is now substantial and is being driven by two means, one is that fungi consume carbs, breath in oxygen and burn them to exhale carbon dioxide, the other is that they don’t have water holding cell walls and are always losing water to the environment. The spores mature fast as once it’s cracked open all the plant cells it’s on a ticking clock before it loses too much water to survive. Many fungi can go dormant in dry conditions but this need for water they can’t hold onto is what links mold to wet and damp.

At around 208 days there’s another outbreak and unfortunately I don’t know enough to say if it’s a different species, but it again shows the radial growth.

From there we get some bugs and a cellar spider but the spores turn brown as they die, and the whole mass dehydrates to practically nothing.

[JoeP]

That is kinda fun. And oh look, the guy has lots of other timelapse videos.

Originally Posted by Ari

although it could be sped up even more.

YouTube playback speed x 2 ftw.


It's kind of impressive that there's almost no change in the first 60 days. Do you see any information on the ambient temperature?

[JoeP]

FF double posting ftl.

[JoeP]

Persons of a sensitive disposition any disposition whatsoever should probably avoid the minced meat one.

[But]

[Kamilah Hauptmann]

Put it side by side:

It occurs to me that part of the reason that America hasn't begun using centigrade is that it's always - since the 70s - been presented as a matter of SWITCHING. If we'd just gone about ADDING it to Fahrenheit, we'd already all be bimetric fluent.

— Chris Maytag����*⬛����️������ (@cpm5280) February 11, 2021

[Kamilah Hauptmann]

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[beyelzu]

Sexual division of labor with females as gatherers and males as hunters is a major empirical regularity of hunter-gatherer ethnography, suggesting an ancestral behavioral pattern. We present an archeological discovery and meta-analysis that challenge the man-the-hunter hypothesis. Excavations at the Andean highland site of Wilamaya Patjxa reveal a 9000-year-old human burial (WMP6) associated with a hunting toolkit of stone projectile points and animal processing tools. Osteological, proteomic, and isotopic analyses indicate that this early hunter was a young adult female who subsisted on terrestrial plants and animals. Analysis of Late Pleistocene and Early Holocene burial practices throughout the Americas situate WMP6 as the earliest and most secure hunter burial in a sample that includes 10 other females in statistical parity with early male hunter burials. The findings are consistent with nongendered labor practices in which early hunter-gatherer females were big-game hunters.

Female hunters of the early Americas | Science Advances

[JoeP]

10 hours to go, 750,000km to go:
Mars 2020 Perseverance Rover - NASA Mars

The Perseverance Rover will attempt to land on Mars today. "Seven minutes of terror" descending through the atmosphere. Live broadcasting begins 11:15 a.m. PST / 2:15 p.m. EST / 19:15 UTC.

7 Minutes to Mars: NASA's Perseverance Rover...

[ceptimus]

It's more-or-less the same as the Curiosity rover which landed using the same method back in August 2012 - it doesn't seem that long does it? Since then, Curiosity has driven just over fifteen miles - so an average speed of just 0.0002 mph - it doesn't move at all on most days.

Perseverance has a different suite of instruments, and upgraded tires that are supposed to better withstand the Martian rocks and soil - Curiosity's tires are badly worn after just fifteen miles of travel.





Good luck Perseverance! If it survives the risky landing procedure intact, I'm sure it will send back some great photos.

[JoeP]

Touchdown.

[JoeP]

The guys seemed pretty pleased



Engineering camera a few seconds after touchdown.

[JoeP]

I was having a discussion with Miisa about whether it matters if you put items in the centre of the microwave or further out, so I've been on numerous web pages about it. And then videos.

It turns the wavelength of a typical microwave oven's microwaves is about 12cm, and you definitely do get standing waves and patches with a lot more heating than others.

Microwave Oven Standing Wave Visualization -...

I was v. surprised at how localised the heating is.

Because the video is more than 2 minutes long, here's a still:


(He says it looks like a face but he's got it upside down)

show spoiler

The hotspots are localised in 3D so will be at different places at different heights. And he includes one with the turntable and it's satisfyingly even. I suppose the centre still might not be evened out in some microwaves.

How a Microwave Oven Works - YouTube

This guy explains standing waves. Though he's wrong in saying a microwave heats food even throughout - in fact they only penetrate a few centimetres.

Which could be the whole of something like a grape:

How Microwaving Grapes Makes Plasma - YouTube

[BrotherMan]

I now feel smrter for placing any foods just off of center for microwaves with a turntable.

[ceptimus]

The standing waves thing is why consumer microwaves usually have the same internal width: it has to be a whole number of wavelengths, and the wavelength is 4.8 inches. Commercial microwaves often operate at a lower frequency (915 MHz instead of 2.45 GHz) so their wavelength is 12.9 inches.

[JoeP]

Perseverance Rover’s Descent and Touchdown on...

The first video of a landing on Mars.

NASA’s Mars Perseverance Rover Provides First Audio Recording on Mars | NASA

[Kamilah Hauptmann]

DvTGy.jpg

[Kamilah Hauptmann]

aerodynamics of a cow pic.twitter.com/4rkJlggagb

— Cow (@EveryDayCows) February 28, 2021

[BrotherMan]

Sorry, that belongs in the Fly By Science thrad.

[But]

Originally Posted by JoeP

I was having a discussion with Miisa about whether it matters if you put items in the centre of the microwave or further out, so I've been on numerous web pages about it. And then videos.

It turns the wavelength of a typical microwave oven's microwaves is about 12cm, and you definitely do get standing waves and patches with a lot more heating than others.

Microwave Oven Standing Wave Visualization - YouTube
I was v. surprised at how localised the heating is.

Because the video is more than 2 minutes long, here's a still:


(He says it looks like a face but he's got it upside down)

show spoiler

The hotspots are localised in 3D so will be at different places at different heights. And he includes one with the turntable and it's satisfyingly even. I suppose the centre still might not be evened out in some microwaves.

Here you can see it much better:

Speed of Light, Microwave Oven and How It Works -...

[ceptimus]

The speed of light is now DEFINED as a fundamental constant. So any experiment to "measure the speed of light", is now actually an experiment to establish how long a metre is. But if you can do this with incredible accuracy, how do you present your results? Probably the best you can do is to say something like, "We now know that a metre is 0.00000...XXX % longer (or shorter) than we used to think it was."

[But]

Originally Posted by ceptimus

The speed of light is now DEFINED as a fundamental constant. So any experiment to "measure the speed of light", is now actually an experiment to establish how long a metre is. But if you can do this with incredible accuracy, how do you present your results? Probably the best you can do is to say something like, "We now know that a metre is 0.00000...XXX % longer (or shorter) than we used to think it was."

I can measure the speed of light in terms of the length of my foot. That's perfectly fine, as it always has been. And when the speed of light starts changing randomly, I get the last laugh.

[But]

As far as we know the speed of light is a constant and therefore we have defined the meter in terms of the speed of light and the second, which fixes the numerical value of the speed of light in meters per second. To say that we can't measure the speed of light is like telling Ole Rømer that the king has just redefined all the units so what he's actually done by observing Io is measure the price of fish.

[Kamilah Hauptmann]

Facial recognition technology can expose political orientation from naturalistic facial images | Scientific Reports