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Interactive "Eyes on the Solar System" (NASA)

Posted onApril 4, 2026April 4, 2026AuthornetjeffLeave a comment

This in-browser Solar System viewer is pretty nice, https://eyes.nasa.gov/apps/solar-system. Best viewed on larger screens (tablet/laptop/desktop) but also works on smaller phone screens.

It lets you zoom around, focus on things, lots of options to control what's shown. Also some time-travel into past/future. This is from NASA, so emphasis is on the kinds of thing that NASA is interested in. You can find things just by scrolling/zooming around, but if you know what you want you can use the search at the top (magnifying glass icon).

For really high profile things like Voyager 2 (link) there's a timeline view that lets you timetravel quickly get to the "interesting" bits of the mission.

I happen to be posting this while Artemis 2 (link) is on it's way to the Moon flyby. For missions that are live, it shows current position. After the mission, you can use timetravel to view where it went.

NASA has several other "Eyes" apps, that focus on things a bit more: https://science.nasa.gov/eyes/

The 2024 almost-backdoor on the Internet

Posted onMarch 8, 2026March 8, 2026AuthornetjeffLeave a comment

Veritasium recently released an excellent video about the almost-backdoor into OpenSSH in 2024. The attackers (Russia? China?) would have had a secret backdoor into the majority of servers worldwide. The Internet came within several weeks of this disaster.

The video provides lots of context, in addition to the almost-backdoor, including: history of the "open source" movement; background on Linux; remote access encryption & OpenSSH; and how compression works.

If you're already familiar with all that, you can skip 20 minutes of this hour long video. Start at 9:12. When it gets to about 12:00 (about encryption), skip ahead to 23:26 and watch the rest of the video.

If you want to learn more, start with "XZ Utils backdoor" on Wikipedia.

Wikipedia offline

Posted onNovember 30, 2025December 7, 2025AuthornetjeffLeave a comment

Every few years I look into having an offline copy of wikipedia. Don't know why, just something that feels like I should have. Here's what worked well for me in late 2025.

YouTube parodies: Fun with generative AI

Posted onNovember 24, 2023November 30, 2025AuthornetjeffLeave a comment

Two creators on YouTube (YT) that I follow (and support) are Kurzgesagt (In a Nutshell) and CGPGrey. I stumbled across this fan made parody, "Every Kurzgesagt Video Ever". In the description on the parody video, the author jokingly wrote, "I'm coming for you next CGPGrey".

Which got me to thinking, I wonder how good generative AI would be at writing the script for a parody of CGPGrey? Here's the same prompt I used for all of them:

Write a script in the style of Youtube creator CGPGrey, that is a a parody of CGPGrey videos.

A couple of them did a pretty good job, one not so much. I've linked their responses, and at the end of this post is a complete copy of each response.

"Tricky questions" that help to understand physics

Posted onOctober 7, 2023November 30, 2025AuthornetjeffLeave a comment

Here are two "tricky questions" that are really interesting to help understand physics.

Attach a tennis ball to string, and swing it over your head. The ball follows a circular path. Release the string. What path does the ball follow?
The speed of light is 300,000 km per second, typically shown as the letter c. Take two pieces of wire each 300,000 km long. Place a light bulb and a battery 1 meter apart. Connect the light bulb to each wire. Before connecting the battery, stretch out the wire as far as you can on each side. Now connect the battery. How long until the bulb lights up? 0.5 seconds, 1 sec, 2 secs, or 1/c secs?

Why are these "trick questions"? Because of the assumptions we usually make when thinking about questions like these. Picking apart these assumptions reveals a lot about how physics works.

Password advice

Posted onNovember 10, 2022November 30, 2025AuthornetjeffLeave a comment

Friends & family sometimes ask me for advice about passwords. I've captured this advice for the benefit of others, and to make it easier for me answer questions in the future. See netjeff.com/password-advice

RV electrical

Posted onSeptember 24, 2019December 20, 2021Authornetjeff4 Comments

This is a summary diagram I created to help people new to RV's better understand the electrical systems in an RV. The direction of the arrows shows the flow of power. This diagram might not exactly match your specific RV, but the overall idea is applicable. Also, this does not show all the details. The usual disclaimer applies, that before working on your RV electrical systems you should get actual training, and consult the detailed diagrams for your specific RV.

If would like to print this, here it is as a Powerpoint slide.

Converting my Weber Q1200 to use both low-pressure RV connector and standard tanks

Posted onMay 28, 2018August 9, 2023AuthornetjeffLeave a comment

Last week I converted our Weber Q1200 gas grill to use both the low pressure connector on our RV, and standard (high pressure) 1, 5, 10, & 20 lb tanks.

I followed the instructions in this YouTube.com video. Here are the exact parts I bought on Amazon for the conversion, and hoses to connect to RV and standard tanks.