explain xkcd - User contributions [en]

2274: Stargazing 3

2020-02-29T04:18:55Z

Johnrb:

{{comic
| number = 2274
| date = February 28, 2020
| title = Stargazing 3
| image = stargazing_3.png
| titletext = If we can destroy enough of the lights in our region, we may see more comets, but that's a risk we'll have to take.
}}

==Explanation==
{{incomplete|Created by a TERRIFIED LAMP. The explanation, for the most part, doesn't exist. Do NOT delete this tag too soon.}}

This is the third in the Stargazing series. The first [[1644: Stargazing]] appeared four years ago and the second [[2017: Stargazing 2]] one and a half years ago.

{{w|Vega}} is a star in the constellation of {{w|Lyra}}. It does indeed have {{w|Magnitude (astronomy)|magnitude}} 0.03 and is the brightest star mentioned in this comic. The phrase <q>It's the brightest star I'm currently talking about</q> is an example of the technically correct but not at all useful information that is typical of the Stargazing series. Vega is only the {{w|List of brightest stars|5th brightest star}} (outside of the Sun), as {{w|Sirius}} is the brightest visible star.

{{w|Polaris}} is indeed the star over the North Pole, and is commonly called the North Star or the Pole Star. It has been used for navigation, as it appears fixed in the night sky. It is the brightest star in the constellation Ursa Minor, but there are about fifty other stars that are as bright as it is (magnitude 2), so it's not really remarkable, as the host says. In fact, it isn't even always the pole star, as Earth's axis precesses in a 26,000 year cycle.

{{w|Comets}} are small rock and ice particles. Many comets have usually highly elliptical orbits around the sun and so they are seen "every few decades". Yelling at comets has proved to be an ineffective way to make them go away.{{Citation needed}}

{{w|Light pollution}} is indeed a problem with stargazing. Light pollution is the presence of artificial light in the night sky, which makes it very difficult to see stars. Stargazing in remote locations is remarkably different than in populated cities. Light pollution was previously discussed in [[2121: Light Pollution]].

Light pollution does not actually make the "sky go away", but it does affect how humans can see stars or other astronomical features in the sky. An [http://sonic.net/~rknop/php/astronomy/classes/a103/sum2006/info/angdist.shtml#xbow astronomy crossbow]" is a tool used to measure the angular distance between stars. They cannot shoot real {{w|crossbow bolt}}s, but any type of crossbow or other weapon could be used to destroy lights and "preserve" the sky. The title text mentions that destroying lights could allow for the viewing of comets, which is true. It is unclear why the host dislikes comets so much.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[In a dark panel, a TV host stands in front of a group of people: Science Girl, Ponytail, and Cueball; the panel is inverse-colored, i.e. white text and drawings on black]
:Host: Welcome back to Stargazing.
:Host: There are no new stars since last time, but you came back for some reason.

:[Zoomed out on the same scene, the host is now with Science Girl, Ponytail, Cueball, Megan, and White Hat. The host is pointing upwards with her left hand.]
:Host: That star is Vega. At magnitude 0.03, it's the brightest star I'm currently talking about.
:Host: That one is Polaris. It's over the North Pole, which is all it has going for it.

:[A frame-less white panel, zoomed in on the host, who is now pointing upwards with her right hand.]
:Host: That's a comet. Some of them come back every few decades, no matter how much I yell at them.
:Host: But stargazing isn't all fun yelling. We face a problem even worse than comets: light pollution.

:[Back to a dark panel, the host now has a big bag of crossbows. The bag has a logo of a crossbow with stars around it. She has taken out one of them and is holding it in her right hand.]
:Host: The sky is going away because people keep shining lights at it. The new LEDs are even worse - they're too blue, and you can't turn them off by throwing rocks at them like with the old ones.
:Host: Luckily, I brought these astronomy crossbows.
:Host: Take one, then let's fan out and look for lamps.

{{comic discussion}}

[[Category:Comics with inverted brightness]]
[[Category:Astronomy]]
[[Category:Stargazing]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Science Girl]]

Talk:2274: Stargazing 3

2020-02-29T04:14:58Z

Johnrb:

I think the "you can't turn them off by throwing rocks at them like the old ones" is a reference to a reddit comment in a thread about older generations refusing to learn new technology, or something to that extent. One comment detailed a humorous story wherein they had been helping a village install electricity/light bulbs, and this grandmother of the household kept shattering all the bulbs by throwing rocks at them to turn them off, refusing to learn how to use them correctly. I'm trying to search for this, but no luck so far. If this was not a reference to that thread but merely a coincidence, my apologies for making you read all of this. [[User:Wigglebeans|Wigglebeans]] ([[User talk:Wigglebeans|talk]]) 20:55, 28 February 2020 (UTC)wigglebeans
: I remember that comment as well. I feel like it was in ask reddit, but I can't seem to find it either. [[Special:Contributions/172.68.174.128|172.68.174.128]] 23:15, 28 February 2020 (UTC)

Can someone make a category for the Stargazing series? [[1644: Stargazing]], [[2017: Stargazing 2]], and this one. [[Special:Contributions/172.69.34.238|172.69.34.238]] 23:29, 28 February 2020 (UTC)
:Oh, nevermind, it already exists: [[:Category:Stargazing]] [[Special:Contributions/172.69.34.238|172.69.34.238]] 23:31, 28 February 2020 (UTC)

Actually, "no new stars being created" is not just not obvious, it would need grant, research and citation. I mean, sure, actually new star (and not just star which started to be more luminous like nova) don't appear that often, and one visible by naked eye even less so, but it still CAN happen - and can easily be overlooked. The estimate is that [https://www.nasa.gov/centers/goddard/news/topstory/2006/milkyway_seven.html seven new stars are formed in our galaxy every year]. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:36, 28 February 2020 (UTC)

Astronomy crossbows are real things. They are used to measure the angular distance between stars. Here's a fancy one (used) for sale for $700, [https://astromart.com/classifieds/astromart-classifieds/misc-other-astronomy/show/crossbow-eqt-200-equatorial-platform] and here is a simple one that is simply a yardstick pulled back into a curve and stuck on the end of a stick [http://sonic.net/~rknop/php/astronomy/classes/a103/sum2006/info/angdist.shtml]. [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 23:51, 28 February 2020 (UTC)

I've got one of those expensive crossbows from Gregg Blandin. It's an equatorial platform that allows a simple dobsonian telescope to track the stars. It has nothing to do with measuring angular distances. So I changed the link to the astronomy course that uses the simple type to measure angular distances. [[User:Johnrb|Johnrb]] ([[User talk:Johnrb|talk]]) 04:14, 29 February 2020 (UTC)

2274: Stargazing 3

2020-02-29T04:04:36Z

Johnrb: /* Explanation */

{{comic
| number = 2274
| date = February 28, 2020
| title = Stargazing 3
| image = stargazing_3.png
| titletext = If we can destroy enough of the lights in our region, we may see more comets, but that's a risk we'll have to take.
}}

==Explanation==
{{incomplete|Created by a TERRIFIED LAMP. The explanation, for the most part, doesn't exist. Do NOT delete this tag too soon.}}

This is the third in the Stargazing series. The first [[1644: Stargazing]] appeared four years ago and the second [[2017: Stargazing 2]] one and a half years ago.

{{w|Vega}} is a star in the constellation of {{w|Lyra}}. It does indeed have {{w|Magnitude (astronomy)|magnitude}} 0.03 and is the brightest star mentioned in this comic. The phrase <q>It's the brightest star I'm currently talking about</q> is an example of the technically correct but not at all useful information that is typical of the Stargazing series. Vega is only the {{w|List of brightest stars|5th brightest star}} (outside of the Sun), as {{w|Sirius}} is the brightest visible star.

{{w|Polaris}} is indeed the star over the North Pole, and is commonly called the North Star or the Pole Star. It has been used for navigation, as it appears fixed in the night sky. It is the brightest star in the constellation Ursa Minor, but there are about fifty other stars that are as bright as it is (magnitude 2), so it's not really remarkable, as the host says. In fact, it isn't even always the pole star, as Earth's axis precesses in a 26,000 year cycle.

{{w|Comets}} are small rock and ice particles. Many comets have usually highly elliptical orbits around the sun and so they are seen "every few decades". Yelling at comets has proved to be an ineffective way to make them go away.{{Citation needed}}

{{w|Light pollution}} is indeed a problem with stargazing. Light pollution is the presence of artificial light in the night sky, which makes it very difficult to see stars. Stargazing in remote locations is remarkably different than in populated cities. Light pollution was previously discussed in [[2121: Light Pollution]].

Light pollution does not actually make the "sky go away", but it does affect how humans can see stars or other astronomical features in the sky. An [http://sonic.net/~rknop/php/astronomy/classes/a103/sum2006/info/angdist.shtml astronomy crossbow]" is a tool used to measure the angular distance between stars. They cannot shoot real {{w|crossbow bolt}}s, but any type of crossbow or other weapon could be used to destroy lights and "preserve" the sky. The title text mentions that destroying lights could allow for the viewing of comets, which is true. It is unclear why the host dislikes comets so much.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[In a dark panel, a TV host stands in front of a group of people: Science Girl, Ponytail, and Cueball; the panel is inverse-colored, i.e. white text and drawings on black]
:Host: Welcome back to Stargazing.
:Host: There are no new stars since last time, but you came back for some reason.

:[Zoomed out on the same scene, the host is now with Science Girl, Ponytail, Cueball, Megan, and White Hat. The host is pointing upwards with her left hand.]
:Host: That star is Vega. At magnitude 0.03, it's the brightest star I'm currently talking about.
:Host: That one is Polaris. It's over the North Pole, which is all it has going for it.

:[A frame-less white panel, zoomed in on the host, who is now pointing upwards with her right hand.]
:Host: That's a comet. Some of them come back every few decades, no matter how much I yell at them.
:Host: But stargazing isn't all fun yelling. We face a problem even worse than comets: light pollution.

:[Back to a dark panel, the host now has a big bag of crossbows. The bag has a logo of a crossbow with stars around it. She has taken out one of them and is holding it in her right hand.]
:Host: The sky is going away because people keep shining lights at it. The new LEDs are even worse - they're too blue, and you can't turn them off by throwing rocks at them like with the old ones.
:Host: Luckily, I brought these astronomy crossbows.
:Host: Take one, then let's fan out and look for lamps.

{{comic discussion}}

[[Category:Comics with inverted brightness]]
[[Category:Astronomy]]
[[Category:Stargazing]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Science Girl]]