Wikipedia:Reference desk/Archives/Science/2020 July 30

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July 30

Countries playing their national anthems before space launches

I've noticed that NASA plays the US national anthem before launches (at least during their livestreams). Do other countries that launch spacecraft do the same as well? For example, do Russian livestreams for Soyuz launches play the Russian anthem, does ESA play the French and/or European anthems before Ariane and Vega launches, etc.? Narutolovehinata5 ^tccsdnew 11:36, 30 July 2020 (UTC)

In Russia "Grass by the Home" ("Trava u doma") has been played before every launch at Baikonur Cosmodrome as an unofficial anthem of astronauts (as reported by Roskosmos, and in 2009 Roskosmos reportedly made it an official anthem of Russian astronauts). Brandmeister^talk 19:52, 30 July 2020 (UTC)

Huh. Kind of reminds me of Robert Heinlein's The Green Hills of Earth.--Khajidha (talk) 23:27, 3 August 2020 (UTC)

Blue whale and Argentinosaurus

According to Blue whale, "it is the largest animal known to have ever existed", "reaching a maximum confirmed length of 29.9 meters (98 feet)", but per Argentinosaurus its length estimates range from 30 to 39.7 metres (98 to 130 ft), meaning it was larger by length and not only among "land animals of all time". Should one of the articles or both be corrected? 212.180.235.46 (talk) 12:31, 30 July 2020 (UTC)

Length and size are two different things. See Largest organisms. --Guy Macon (talk) 12:50, 30 July 2020 (UTC)

To support what Guy Macon said, Argentinosaurus may have been long, but that doesn't mean it was "bigger," since it could be long but comparatively skinny. Estimates on its mass range from 50 - 100 tons. Blue whales are more like 170 tons. --OuroborosCobra (talk) 14:30, 30 July 2020 (UTC)

Turns out that Argentinosaurus wasn't the longest dinosaur. Supersaurus was slightly longer. (But blue whales are heavier than either one.)

--Guy Macon (talk) 14:59, 30 July 2020 (UTC)

Given the large uncertainties in the lengths of those dinosaurs, in particular those of which the necks and tails were never actually found, I don't think we can say with any certainty which ones were or were not longer than a blue whale. PiusImpavidus (talk) 08:12, 31 July 2020 (UTC)

This Britannica article says "[Argentinosaurus] was thought to have weighed 90 to 100 metric tons (99 to 110 tons)" whereas our blue whale article says that Antarctic females average 130 tons (118 metric tonnes). So still the biggest in terms of mass. Alansplodge (talk) 12:59, 31 July 2020 (UTC)

Why is dew important for plants?

As far as I know it's possible for a plant to leave without dew (we have flowerpot in the kitchen...), then what's the rule that dew play in nature if it isn't necessary? I mean we have rain already and why do we need also dew? --ThePupil (talk) 15:45, 30 July 2020 (UTC)

Here's one article on the subject.[1] House plants are in a controlled environment, while plants in the wild are at the mercy of nature. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:52, 30 July 2020 (UTC)

The tone of your question seems odd, like you're arguing to abolish the practice of dew. Our article does a good job of explaining "how" it forms, but as to the "why", see teleological argument. There is no "why". Dew happens, and plants and animals may make use of it or not. 64.235.97.146 (talk) 16:23, 30 July 2020 (UTC)

Exactly. Dew is condensation, a simple physical process. It does not have a "role" and it cannot be said to be "needed" or "necessary" (or unnecessary, for that matter) in the sense the original poster is using. Plants may have various adaptations to dew, but that is a function of their biology evolving to fit the environment, not the environment filling some "need". --Khajidha (talk) 16:56, 30 July 2020 (UTC)

In arid and semi-arid regions or in a dry season, dew may be the main or only water resource for many plants, some of which can absorb moisture through their leaves.--Shantavira|^{feed me} 19:49, 30 July 2020 (UTC)

But again, that's a property and function of the plant, not the dew. --Khajidha (talk) 22:29, 30 July 2020 (UTC)

Nevertheless, it's important to the plants that use it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:54, 31 July 2020 (UTC)

Yes, this goes to the question in the section title: "Why is dew important for plants?" --47.146.63.87 (talk) 00:45, 2 August 2020 (UTC)

And as 64.whatever pointed out, that's not a good question. Some plants utilize dew, some don't. "How do some plants utilize dew?" would be a good question. --Khajidha (talk) 14:21, 2 August 2020 (UTC)

Or through their roots. The spines and other structures on many cacti increase surface area, which among other things causes more dew to condense. The dew can then drip down to the ground and be soaked up. The spines themselves are highly-derived leaves with no stomata to absorb water. --47.146.63.87 (talk) 00:45, 2 August 2020 (UTC)