Talk:Astronomical unit

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Astronomical unit was nominated as a Natural sciences good article, but it did not meet the good article criteria at the time (April 10, 2018). There are suggestions on the review page for improving the article. If you can improve it, please do; it may then be renominated.

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Two more examples

The table "Examples" in this article gives a wonderful sense of relative sizes, although not strictly required in this article on the astronomical unit. / / I would like to suggest two lines be added at the bottom: distance to the nearest extra-galactic object, and distance to the nearest galaxy. I would attempt to add them myself, but I would only have wikipedia to go on, which I believe is not quite the standard required. Nick Barnett (talk) 10:47, 7 February 2023 (UTC)[reply]

why is Earth the only planet that people living on it 41.121.99.100 (talk) 16:51, 5 November 2023 (UTC)[reply]

Because on Earth 🌍 there is Water 💦,Soil and Air 41.121.99.100 (talk) 16:53, 5 November 2023 (UTC)[reply]

Rounding errors, or contradicting sources

This article in #Development_of_unit_definition:

> 1 astronomical unit [..] ≈ 499.004783836 light-seconds

Same article, in the table at #Examples:

> Light-second [≈] 0.0019 [au]

I would expect that rounded value to be 0.002 or more, not less. 2A10:3781:11DB:1:1993:C326:C2A3:B78 (talk) 14:12, 16 December 2023 (UTC)[reply]

I agree. Light-second expressed in au is 149,597,780,700 / 299,792,458 = 0.002003989. I made the change Jc3s5h (talk) 16:30, 16 December 2023 (UTC)[reply]

improved

The article mentions the improved measurement of the speed of light in 1983. The way I know it, is that the ability to measure time, or frequency, improved, but the ability to accurately measure distance did not. So, defining c increases the ability to measure distance. But also, defining c means that it is now measured infinitely accurately, by definition. Or, the other way to look at it, you can't measure the speed of light anymore. Gah4 (talk) 09:51, 14 April 2025 (UTC)[reply]