A neat dashboard. The usage of metric units can be improved:

> Corona ~1.2M K / Active Regions ~2M K / Hot Flares ~6.3M K / Flare Plasma ~10M K / Active Corona ~2.5M K / 10M K Hottest flare plasma

If "M" means "million", then it's correct but not the best way to express things. If "M" means "mega", then there must be a space after the number and no space before the unit of kelvin - it needs to be written as "1.2 MK" (megakelvins), "2 MK", etc.

> The Cosmos at a Glance / 1.4M km Solar diameter

If "M" means "million", then it's correct but really not the best way to express things. If "M" means "mega", then stacking prefixes is not allowed in metric - it needs to be written as "1.4 million km" (full number word), "1 400 000 km", or "1.4 Gm (gigametres)".

In general publications, any length unit bigger than the kilometre is extremely uncommon. But this aversion to large prefixes is weird because we are (forced to be?) routinely comfortable with megahertz, gigahertz, megabytes, gigabytes, terabytes, megapascals (material strength), megaohms (insulators), megavolts (the highest voltage transmission lines). I see no good reason to avoid megametres, gigametres, etc. But the unspoken convention is to write "thousand kilometres", "billion kilometres", etc.

> The Cosmos at a Glance / 3,000 km/s Fastest CME speed

This fact is given in kilometres-per-second, but a bunch of other facts are given in kilometres-per-hour. This makes it much harder to compare their relative magnitudes. It's similar to the problem of comparing airplane speeds in knots versus bullet speeds in feet per second. These units aren't wrong individually, but think carefully about when to switch units and when not to.

> The Sun facts / A dynamic sphere of plasma photographed by NASA’s SDO every 12 seconds in 12 wavelengths — from the 5,000 K surface to 10-million-degree flare plasma.

Don't switch units mid-sentence from kelvins to degrees (and which type of degree?). Compare "5 000 K" with "10 000 000 K". It's correct but less common to say "5 kK vs. 10 000 kK" (kilokelvins).

> The Sun facts / The Sun’s core burns at 15 million °C — hot enough to fuse 600 million tons of hydrogen into helium every second.

I would like to note that 600 million tons (megagrams) is 600 Tg (teragrams). But it's also an unspoken convention to avoid units of mass larger than kilogram, so it's rare to see megagrams, gigagrams, etc. in writing.

> The Sun facts / The Sun’s surface gravity is 28 times stronger than Earth’s. A 150-pound person would weigh 4,200 pounds there.

I would prefer not to see the unit of pounds in the discussion, and also the sentence conflates mass with weight. Reworded with extra notes: A 70-kilogram person (anywhere in the universe) would feel like they weigh 1900 kg on Earth (18.7 kilonewtons).

> The Sun facts / Sunspots are cooler regions — about 3,500°C compared to the 5,500°C surface — but are still incredibly hot.

You mostly used kelvins to talk about the Sun, but now you're using degrees Celsius for a few facts?

Before anyone accuses me of pedantry, please remember: Clarity matters in communication. We have spelling and grammar rules in English, and there are also rules in technical syntax such as expressing quantities using the metric system.

Also, people copy each other, so setting a good example is not just about the current reader, but also future writers and readers. To give an example, almost no one uses the unit "kelvin" correctly, and the bad usages keep getting propagated. Incorrect - "4000-Kelvin light bulb" (adjective form, uppercase), "temperature of 273 degrees kelvin". Correct - "4000-kelvin light bulb" (adjective form, lowercase), "temperature of 273 kelvins" (non-adjective form requires plural). The unit of kelvin must be treated no differently than joules, watts, newtons, etc.

The purpose of standards is to reduce the space of possibilities, which makes it easier for writers to choose what to write and easier for readers to understand the correct intended meaning. As an example, the symbol for metre is just "m", no others. Some ad hoc sloppy abbreviations for metre include: "M" (conflicts with mega), "mtr", "mtrs", "ms" (conflicts with millisecond). For writers and readers alike, it's much easier to learn the single symbol rather than four or more ways of expressing the same unit. Similarly, gram is "g", but I've seen supermarkets with labels like "gm"; kilometre is "km", but I've seen "kms" as an ad hoc plural.

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