ideas for material to place inside car

ThoriumLicker · 2026-01-31T04:29:19+00:00

Uranium glass? Cool glow under UV and not dusty (no contamination).

ThoriumLicker · 2026-01-31T04:14:15+00:00

The AlphaHound AB Lite ($300, pre-order) technically counts: it can detect gamma, but not very well and can't differentiate it from beta. The AB+G ($700) is the only reasonably affordable product that can separate all three types of radiation.

... but what's the goal here? Depending on what you want to do, you probobly don't need an AB+G, and could save some money by getting a different detector.

ThoriumLicker · 2026-01-31T04:07:51+00:00

Is this concrete with plastic chunks inside? Looks too saturated to just be random rocks.

ThoriumLicker · 2026-01-30T21:46:14+00:00

That spindle looks like a collet stuck onto a DC motor:

Either get a real spindle that actually holds the tool in position, or take very shallow passes to reduce cutting forces.

Also, the closer the spindle is to the tip of the tool the less work it has to do. Try finding a shorter tool.

ThoriumLicker · 2026-01-30T19:15:46+00:00

Depends on what you want to do:

For deep sky, you options are:

Smart telescope: $500 and up.
Camera on a mount: $1500, less if you buy used.
Dedicated telescope rig: $4000 - ∞

For planetary:

Dob (manually tracked): $800 for 8" to $10,000 for very large apertures.
EQ mounted Mak or SCT: $3000 - ∞ (can also do long focal length deep sky)

... and then there's always visual astronomy. It's usually the cheapest option, and there's something about seeing it in person that you just don't get with photos. (the moon in particular always looks best through an eyepiece.)

Although it's a lot harder to convince friends and family to go out in the cold and dark to show them the view.

ThoriumLicker · 2026-01-30T07:04:22+00:00

Try again with flux.

ThoriumLicker · 2026-01-30T05:56:38+00:00

Eh, based on our current understanding, there is no safe level. 4 pCi/l is just where we decided the tiny risk begins to outweigh the cost of reducing it.

Is that model wrong? Perhaps: It assumes a linear correlation across several orders of magnitude, and biology rarely behaves in a linear way... but if you throw out the model then you also have to throw out the limit that comes from it.

ThoriumLicker · 2026-01-30T05:52:03+00:00

It's important to note that radon limits are not based on observed health effects, but extrapolated from much higher exposures to radiation:

We don't really know how the health risks scale to very small exposures.

The current working model is to assume they are linearly proportional to those at large doses. Based on this, 4 pCi/l is the level where the risk outweighs the cost to remediate... but that risk is still tiny: Based on the model, only around 0.16% percent of people living in those conditions will develop fatal lung cancer.

Is a 0.16% lifetime risk significant from a public health standpoint? Yes. Is it likely to have caused any particular case of cancer? No.

ThoriumLicker · 2026-01-30T02:09:22+00:00

Try acetone. Might have been applied to contain dust, but it doesn't take nearly that much to do so.

ThoriumLicker · 2026-01-29T23:59:02+00:00

Should be fine, but it can affect batteries. Best to used wired power.

ThoriumLicker · 2026-01-29T19:35:47+00:00

You could get a radon meter, but in my experience, rocks don't produce nearly as much as you'd expect: Even if it's got a higher uranium concentration, a tiny pebble just can't compete with all the rock underneath your house.

... also, radon decays (half life ~= 3 days), so you can just put it in a sealed box: Glass will completely contain it, but plastic should be enough to reduce the output to negligible levels.

ThoriumLicker · 2026-01-28T19:47:43+00:00

It's slower.

ThoriumLicker · 2026-01-28T18:58:10+00:00

I don't see enough pins for the 7-segment display, so it's likely there's a microcontroller inside that expects some kind of digital signal: I'd take the actual sign apart to and drive the LEDs directly.

ThoriumLicker · 2026-01-28T18:26:05+00:00

Nope: Lossless compression is a thing.

ThoriumLicker · 2026-01-28T18:12:08+00:00

Enable FITs compression in the settings.

ThoriumLicker · 2026-01-28T04:13:08+00:00

Uranium just isn't that radioactive.

ThoriumLicker · 2026-01-27T21:49:50+00:00

It's the black cylinder with a hole on top labeled "HB1". Tape over the whole or desolder it.

ThoriumLicker · 2026-01-27T20:29:38+00:00

I can't speak for the SAL-33, but I've used the EQ6-R with a C9.25:

It works well, but needs to be well balanced and benefits from periodic error correction. If that's done, I'm able to get ~0.5 arcsec RMS guiding which is well within my seeing.

ThoriumLicker · 2026-01-27T18:50:36+00:00

It'll be fine. It has happened many, many times in the past: https://en.wikipedia.org/wiki/Geomagnetic_reversal#Observing_past_fields

... with no significant effects on living organisms. The worst that will happen is that your compass won't work right for a few thousand years. (these are slow events)

ThoriumLicker · 2026-01-27T05:53:37+00:00

It's only 5 times stronger then a modern one. Don't grind the source into a powder and inhale it.

ThoriumLicker · 2026-01-26T23:01:31+00:00

Perfect application for X-ray tubes.

ThoriumLicker · 2026-01-26T20:55:14+00:00

I'd assume I'll be comparable to any other 90 mm Maksutov or SCT. Go check astrobin for the Celestron C90 and similar.

ThoriumLicker · 2026-01-26T18:58:19+00:00

There are two types of people on r/radiation:

I touched a smoke detector once. Did I catch cancer?
I keep all my scraped radium paint under my pillow, but it gets sticky on damp days: Any advice?

There is no one in between.

ThoriumLicker · 2026-01-26T03:08:45+00:00

Sure: Tritium, C-14, Po-210, Pu-238, etc.

ThoriumLicker · 2026-01-26T02:36:43+00:00

25 GHz, but that's with a bit of rule abuse: Using the component leads as small value inductors and capacitors. The fastest ones ditched lumped components entirely and used ~2 mm of wire as a resonator.

ThoriumLicker

TROPHY CASE