James Webb Space Telescope detects water vapor around alien planet
space.com
space.com
"habitable as we know it" is already ruled out by the 430 degree Celsius surface temperature of the planet that was mentioned in the article.
Sure would be something if such planets could have atmospheres. That’d seem to imply a temperature gradient from the hot to cold side and would provide a mechanism for heat transfer.
Maybe this is an industry term, but for layman - it sounds like its saying "where ET lives" and we found water on ET's planet.
I think they were going for "planet not in our solar system" which is properly termed an exoplanet.
Sadly not. They went through an enormous amount of effort to keep it from having to look anywhere near Earth.
Here’s what it would see if it could, though: https://webbtelescope.org/contents/articles/what-would-earth...
Should GJ 486 b have a thin atmosphere or no atmosphere at all then the hottest region of its dayside should be directly under the red dwarf star. If this hottest point is offset, however, this could indicate the presence of an atmosphere that is thick enough to circulate heat.
Given that GJ 486 b is one-third the size of Earth, and orbits its star at one half of one percent the distance from Earth to the Sun, we can resolve where thermal intensity is highest on the planetary surface at a distance of 26 light years and despite the nearness of the star itself ... is pretty mind-blowing.
The letter "a" refers to the star, the letter "b" refers to the first exoplanet discovered, "c" to the second, etc.
Are there any discovered planets where a year is confirmed to be a day?
It's that "low" because its star also radiates way less energy than our sun.
But still, "habitable zone" means liquid water, which you might not find there given the pressures/temperatures involved. Maybe sufficiently cold spots could exist in the areas facing away from its star.
So could you say it's in the habitable zone? Depends on your understanding of the term.
Of course we don't know if other chemistries of life are possible, but that doesn't mean we can't define a habitable zone based on what we do know and expand it later if necessary.
As for looking at moons far from the star, it's barely a reliable means of confirming liquid water even within our own system, good luck detecting liquid water on an exomoon orbiting a far out exoplanet.
Mars is in our habitable zone and has plenty of evidence of having had liquid water flowing on its surface. The evidence of it having had conditions which could sustain some Earth-like life on it has only been increasing, making our current idea of habitable zones pretty promising. The fact that it currently doesn't have any liquid water on the surface has little bearing on that.
We have to narrow it down somehow.
“Okay so we have 12 months. About half are 30 days and the other half are 31 days but then ONE of them is 28 days except every fourth year that month with 28 days has a 29th day”
In reference to the above tweet, it might surprise you to know that at times in the past (and per Wikipedia, even in some cultures today[0]) March has been considered the first Month, meaning that the new year would start on March 1, the leap day would be the last day of the year, and September, October, November and December would in fact be the seventh, eighth, ninth and tenth months of the year.
Compare for example the mayan calendar. Or the orthodox, or syrian, or basically any culture's calendar. None make sense.
1. They refer to three distinct and largely independent phenomena: the rotation of the Earth about its axis (day, and subdivisions hours, minutes, and seconds), the orbit of the Moon around Earth (month, with caveats), and the orbit of Earth around the Sun (year). The fact that there is a rough days-based approximation of each is coincidental. Consider that on some planets there is no clear definition of a day (e.g., gas giants with no observable solid ground), or fixed rotational period (the duration of Venus's "day" apparently varies considerably under the influence of winds, and even Earth's day changes measurably due to tidal influences and factors).
2. Collective agreement and tradition are a real bear. It took nearly 500 years for the Gregorian Calendar to be universally adopted --- Russia's "October Revolution" occurred in what most of Europe considered to be November, as Russia had not yet adopted the Gregorian Calendar first introduced in October 1582. And it wasn't even the last country to do so! China's adoption of the Gregorian Calendar occurred in the 1940s. Calendrical decimalisation has been attempted, particularly notably during the French Revolution (amongst the same reforms which brought us the Metric System), as well as in the USSR. Switching to a ten-day week was exceedingly difficult given a) the traditions of seven-day cycles, particularly in religious contexts, as well as an external world based on the seven-day week.
A great book exploring the history of the (mostly) universally-adopted Gregorian system is Eviatar Zerubavel's Seven Day Circle: <https://openlibrary.org/works/OL1962761W/The_seven_day_circl...>
That is, measurable changes to Earth's rotation have been observed following major earthquakes. Small, mind, but measurable.
Why is this interesting? Is it because of the water, or because of the technical capabilities of the instrument?
The main breakthrough is detecting anything at all on an exoplanet which can hopefully expand to more biologically relevant molecules in the future.
That the atmospheric composition detected is water is mostly irrelevant.