Making SD card for Raspberry Pi 5 from Ubuntu 20.04

I have a new SD card: SanDisk 512GB Extreme microSDXC UHS-I Memory Card

That I want to put LibreELEC on for use in a Raspberry Pi 5. The "easily accessible" computer I am typing this from has Ubuntu 20.04.

I downloaded: LibreELEC-RPi5.arm-11.0.6.img.gz, inserted the SD card into my Ubuntu machine, then did the following:

$ gzip -d LibreELEC-RPi5.arm-11.0.6.img.gz
$ lsblk
...
sda           8:0    1 476.7G  0 disk 
└─sda1        8:1    1 476.7G  0 part /media/mike/3731-3564
...
$ sudo dd if=LibreELEC-RPi5.arm-11.0.6.img of=/dev/sda1 bs=4M
137+1 records in
137+1 records out
575668224 bytes (576 MB, 549 MiB) copied, 0.425209 s, 1.4 GB/s

Then I (first soft then hard) ejected the SD card, inserted it into the RPi5, powered it on, and got this:

What might I be missing?

Thanks! I tried Ubuntu's "Startup Disk Creator" - after burning the LibreELEC image on the SD card it told me I could "Use the device to boot Ubuntu on any machine," but... obviously, it actually worked to burn the LibreELEC image:

First try, easy peasy, first boot resized the partition automatically.

If anybody knows, I'd be curious: what does SDC, Balena, Rufus, etc. have that dd lacks?

Quote from chewitt

a GUI for command-line-phobic users, which is probably 80%+ of our userbase

Agreed.

Quote from tokul

"Write to device and not to partition."

You probably won't like my answer about what was lacking in dd command. There is nothing wrong with writing images using dd command on Linux.

Your answer was apparently on hold while I was writing my "what's missing" question. I did mark your reply as "best answer" when I saw it.

I have been using Linux off and on since 1996 - using it as my personal "daily driver" and work environment since 2013. I knew that bit about "device not partition" long ago, but haven't used that knowledge in the last 5 or so years, so I messed it up and the simple GUI app was a quicker fix for me than dredging the less user friendly knowledge out of my brain. Thanks for the refresher... I'm sure I'll forget again by 2029 if I don't keep using it in the meantime.

Back around 2014 I did a lot of work with dd, and I guess what I would say dd is lacking is user friendliness. It's a very powerful tool which kind of invites misuse by people who don't know exactly what they're doing. The GUI apps, by comparison, either don't offer as many options, or the better ones bury the less commonly used options where they aren't accidentally used by novices. I was suspecting there was some kind of flag to set somewhere to make an image bootable when burned to the device, which is why I ended up asking for help on the forum because "man dd" doesn't mention any such flag option, because that's not how it actually works.