The debate over definition of planets can become relevant back home. By some definitions, the Moon could be considered a planet. It's a round planetary body. Since it orbits the Earth, it's obviously just a moon. Except it's big enough that as it gets farther away (a few cm each Earth year), there's a point where their center of gravity can go outside the Earth. Any definition that makes the Moon a planet, makes the Earth-Moon system a binary planet. #astronomy
"Planet Definitions" by XKCD comic (mirror bots @xkcd @xkcdbot ) - All the definitions of a planet, whether they've earned representation or not. https://xkcd.com/3063/ #astronomy #planetary #asteroid #geology #oops #WTF #humor
![XKCD comic #3063 "Planet Definitions" https://xkcd.com/3063/
explanation from ExplainXKCD https://www.explainxkcd.com/wiki/index.php/3063:_Planet_Definitions
transcript truncated to fit alt-text limit:
[A table with 3 columns, labelled "Definition", "# of planets", and "Solar system". The last row is a drawing of the Solar system, with elements included in the definition of the row colored in green]
Traditionalist: Pluto is a planet
Modern: Pluto is not a planet
Expansive: Dwarf planets are planets
Ultratraditionalist: Only the classical planets are planets
Condescending: Only giant planets are planets; the rest are big asteroids.
Simplistic: Anything gravitationally round is a planet
Grounded: Only objects a spaceship has landed on are planets
Regolithic: Anything covered in dirt and ice and stuff is a planet
Lunar: You can't be a planet if you don't have a moon
Solipsitic: Earth is the only planet
Judgemental: Only the prettiest ones are planets
Empiricist: Only worlds that I, author of this table, have personally seen are planets
Marine biologist: Only objects with oceans are planets
Maritime: Only objects with surface oceans are planets
Universalist: They're all planets
Existantialist: What is space itself is a planet???
Spiteful: Only Pluto is a planet
title/mouseover text: Under the 'has cleared its orbital neighborhood' and 'fuses hydrogen into helium' definitions, thanks to human activities Earth technically no longer qualifies as a planet but DOES count as a star.](https://cdn.masto.host/spaceyspace/media_attachments/files/114/162/831/647/915/361/original/7ed60693432fd815.png "XKCD comic #3063 \"Planet Definitions\" https://xkcd.com/3063/
explanation from ExplainXKCD https://www.explainxkcd.com/wiki/index.php/3063:_Planet_Definitions
transcript truncated to fit alt-text limit:
[A table with 3 columns, labelled \"Definition\", \"# of planets\", and \"Solar system\". The last row is a drawing of the Solar system, with elements included in the definition of the row colored in green]
Traditionalist: Pluto is a planet
Modern: Pluto is not a planet
Expansive: Dwarf planets are planets
Ultratraditionalist: Only the classical planets are planets
Condescending: Only giant planets are planets; the rest are big asteroids.
Simplistic: Anything gravitationally round is a planet
Grounded: Only objects a spaceship has landed on are planets
Regolithic: Anything covered in dirt and ice and stuff is a planet
Lunar: You can't be a planet if you don't have a moon
Solipsitic: Earth is the only planet
Judgemental: Only the prettiest ones are planets
Empiricist: Only worlds that I, author of this table, have personally seen are planets
Marine biologist: Only objects with oceans are planets
Maritime: Only objects with surface oceans are planets
Universalist: They're all planets
Existantialist: What is space itself is a planet???
Spiteful: Only Pluto is a planet
title/mouseover text: Under the 'has cleared its orbital neighborhood' and 'fuses hydrogen into helium' definitions, thanks to human activities Earth technically no longer qualifies as a planet but DOES count as a star.")
On this date in 1781, William and Caroline Herschel discovered a new “comet”, which turned out to be the planet now known as Uranus. It was the first new planet to be discovered since ancient times. And William Herschel wanted to call it Georgium Sidius (George’s Star) after his patron King George III of England. The things scientists contemplate to get funding…
IN PHOTOS | See rare 'blood moon' during total lunar eclipse
People around the world got to witness a rare total lunar eclipse coinciding with a full moon, dubbed a blood worm moon, late Thursday into early Friday. Check out the scenes from here and abroad.
#astronomy #photography #nature #News #Canada #CanadaPhotos
https://www.cbc.ca/news/canada/photos/in-photos-see-rare-blood-moon-during-total-lunar-eclipse-1.7483569?cmp=rss
Where are we with the construction of our Extremely Large Telescope (ELT)?
This video takes you on a drone flight over the site in #Chile. We recommend full screen and volume up!
https://www.youtube.com/watch?v=t3GJbCasyOo
To account for some delays, we've updated the ELT schedule, which now has the following main milestones 
Telescope first light (first test observations) expected in March 2029 Instruments installed and commissioned over the course of 2029 and 2030 Scientific first light (first observations with scientific instruments) expected in December 2030
Read more: https://www.eso.org/public/announcements/ann25001/
CIMOLAI/S. Petkovic. Music: Jon Kennedy – Toy Soldiers
Stayed up way too late last night, but did manage to get a descent picture of the lunar eclipse. 
#Astronomy #Astrophotography #LunarEclipse
Images from last night's Lunar Eclipse.
Credit to u/Rainman_72
Source: https://www.reddit.com/r/ypsi/comments/1jb04g6/while_you_were_sleeping/#lightbox
This is the best image I got just as totality began and before the clouds swooped back in and ended the festivities early here. Any pictures at all were better than the #weather forecast led us to expect. #Portland #PNW #LunarEclipse #astronomy #photography #Moon
But clouds came back in a hurry. Maybe #NWS was on to something.
Typical #Portland / #PNW spring #weather. I got some pictures and I'll download them shortly. #LunarEclipse #astronomy #Moon
NWS said 80% cloud cover in #Portland at #LunarEclipse time. So this is better than expected. #astronomy #photography #Moon
I got lucky! Surprisingly, the sky was clear this morning, so I was able to see the beginning of the partial phase of this total lunar eclipse as the moon was setting.
When life gives you clouds on eclipse night… at least you can get kind of cool cloud-eclipse pictures?
Here's the other Mars moon -- Phobos, a bit larger and closer, but still not much more than a space potato.
The Mars Express orbiter captured Phobos circling over the Martian surface, looking like a rock just hanging out in space. (Which is basically what it is.)
https://apod.nasa.gov/apod/ap230731.html #space #science #ESA #astronomy
The eclipse doesn't officially start for another hour or so, but here's the moon, if anyone is wondering what it looks like right now lol
See that little gray rock?
That's Deimos, the mysterious outer moon of Mars, spied yesterday as the Hera spacecraft buzzed by the Red Planet. Little Deimos is just 12km (8 miles) wide.
Such a cool shot.
https://www.esa.int/Space_Safety/Hera/Hera_asteroid_mission_spies_Mars_s_Deimos_moon #space #science #astronomy #photography
#ESA and the Euclid Consortium will have the first larger "Q1" science data release and publication of a major batch of #Euclid science papers coming week, March 19th.
Journalists can receive material under embargo starting tomorrow, March 14th, 12:00 CET. If you are interested then please sign up at
https://blogs.esa.int/forms/subscription-for-under-embargo-press-releases/
Scientists Potentially Found a Three-Body Problem in Space—but the Mystery Is Just Beginning
https://www.popularmechanics.com/space/solar-system/a64162022/space-three-body-problem/
