0 Persons are tagged with #planets

#planets

digit@iviv.hu
Digit

https://www.youtube.com/watch?v=SD1J5uZIljI

listen to what #RandalCarson has to say even in the first minutes here^, about #ExtinctionEvents , #Asteroids , #AsteroidImpacts , #Tunguska , #MeteorShowers , #KTBoundary ,

see if you're also, like me, ready to conclude we're already foolishly dangerously overdue for #SpaceShipsForEverybody

and perhaps we should not have been supressing such technologies for a century, and should cease that immediately, regardless the loss of profits from ending that #ManufacturedScarcity for oil corporations and other convergent interests. Regardless our hubris to think we'll catch it all with #Telescopes , what with all these large (multi kilometer) objects only noticed as they pass, not to mention the likes of #Oumuamua that come crossing the plane most looked and least "protected" by the other #planets' #gravity wells, maybe we should avail ourselves every opportunity, not tie our hands behind our back and blindfold us.

#LookUp #Study #Studies
#ShootingGallery #HottingUp #ExtinctionEvent #OverDue #ChancingIt #WhenNotIf
#WeCanStillMendThis
"The system as it is seems to be built on toothpicks"

One person like that
ramnath@nerdpol.ch
ramnath

This video covers our #sun's local star neighbors and their #planets.

Source: https://youtube.com/watch?v=qOpYYPzVOG4

Quote Compared to gigantic galaxies and star clusters, the #SolarSystem is no more than just a speck of dust. There are thousands of stars within the radius of 100 light years from it. With some of them barely distinguishable against the dark abyss of space, others are so bright that they can be seen even if they are in other galaxies. Besides, there are a lot of invisible objects lurking in the depths of space, too – from massive brown dwarves to rocky exoplanets comparable to our Earth in size. Some of them may harbour life while others may pose a threat.

However, all this diversity is eclipsed by the #scale of our #galaxy.

There are 200 billion stars and over a trillion planets at the very least to be found across its expanses. It is quite impossible to completely explore this great abundance of unique space objects.

Today we will talk about some of the closest ones.

00:00 Intro
01:18 Closest #stars
02:18 Barnard's #star
05:39 Sirius
09:03 Wolf 1061
14:03 Local Interstellar Cloud
15:57 AP Columbae
18:53 Gliese 370
21:44 #Castor
24:47 Local Bubble
27:04 EndingSee less

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eso@loma.ml
Eso|inoffiziell

Ein gruseliges Spinnennetz, magische Drachen oder schemenhafte Geisterspuren? Was siehst du auf diesem Bild des Supernova-Überrests Vela? Diese wunderschöne Farbenpracht zeigt die geisterhaften Überreste eines gigantischen Sterns und wurde hier in unglaublichen Details mit dem VLT Survey Telescope am Standort Paranal der Europäischen Südsternwarte (ESO) in Chile aufgenommen.#ESO #esoorg #Astronomy #Astrophysics #Astronomie #Suedsternwarte #telescopes #detectors #comets #planets #stars #galaxies #nebulae #universe #NTT #VLT #VLTI #ALMA #ELT #LaSilla #Paranal #Garching #Chile
ESO fotografiert den Geist eines Riesensterns

ESO fotografiert den Geist eines Riesensterns

Ein gruseliges Spinnennetz, magische Drachen oder schemenhafte Geisterspuren? Was siehst du auf diesem Bild des Supernova-Überrests Vela? Diese wunderschöne Farbenpracht zeigt die geisterhaften Überreste eines gigantischen Sterns und wurde hier in...

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2 Comments
mkwadee@diasp.eu
Khurram Wadee

#JohannesKeppler was a brilliant #astronomer who studied the motion of #planets. Like everyone, he also had some strange ideas about the heavens, no doubt as a person in the middle ages would about the harmony of worlds and their purported relation to things like the #PlatonicSolids, which was of course bogus. He is probably best known for his famous three laws of #PlanetaryMotion which he reluctantly formulated when he had to abandon the idea that planets only orbit the #Sun in perfect #circles.

His First Law says that planets orbit the Sun in an #ellipse with the Sun at one #focus. Of course, a circle can be thought of as an ellipse where the two #foci have coalesced into one point (zero eccentricity). Here is what the orbit would look like in that case. The angular velocity of the planet is constant in this case and the areas swept out in equal times are identical.
Circular orbit

#Keppler's Second Law states that the areas swept out in equal times are always identical, even for eccentric ellipses. Here are two examples and you can show that the areas of all the sectors in each case are identical. The Sun is labelled S, the other focus is labelled S' and the centre of the orbit is labelled C.
Elliptic orbit e = 0.2
Elliptic orbit e = 0.5
The corollary of this law is that the angular velocity of the planet changes over its orbit, being faster when it is closer to the Sun and slower when it is further away. I have shown the constant-velocity position in red and you can see that it lags behind for half the orbit and leads for the other half.

These animations required me to learn the #mathematics of #CelestialMechanics and I had to find out what terms like #MeanAnomaly, #EccentricAnomaly and #TrueAnomaly are. It also requires the #NumericalSolution of one algebraic equation, which was fun to investigate. All the details are on the #Wikipedia page for Kepler's Laws here:
https://en.wikipedia.org/wiki/Kepler%27s_laws_of_planetary_motion

The third law relates the orbital period to the mean distance from the Sun but that is not covered here.

#MyWork #Maxima #WxMaxima #FreeSoftware #Physics #Astronomy #AnimatedGif #Animation

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mkwadee@diasp.eu
Khurram Wadee

Another #night and another #photograph of #Jupiter. This time you can three of its four big #Moons (they are #Ganymede, #Callisto and #Europa).
Photograph of Jupiter and its moons
I've also included the #snapshot from #Stellarium so you can see the names of each.
Stellarium snapshot of Jupiter

If you compare tonight's #image with the #photograph from 11 days ago, you can see how much Jupiter has moved with respect to the background starts of #Capricorn. Planets literally are wanderers.
Former image of Jupiter

Of course, the real question is this: Is Stellarium a good model of reality or is reality a good model of Stellarium...

#MyWork #MyPhoto #CCBYSA #DSLR #Nikon #D7000 #BackyardAstronomy #Planets

12 Likes
sylviaj@joindiaspora.com
Sylvia J

November 2021 partial lunar eclipse longest for 1,000 years

#18-19November2021

https://solarsystem.nasa.gov/news/2075/full-moon-guide-november-december-2021/
https://earthsky.org/astronomy-essentials/partial-lunar-eclipse-longest-1000-years/
https://www.moongiant.com/moonphases/november/2021/
https://www.drikpanchang.com/eclipse/lunar-eclipse-date-time-duration.html
https://annakovach.com/blog/full-moon-in-taurus-november-2021/

"This is going to be a crazy time for us all, my dear ones! This #Eclipse is about to change our lives for the better. It might feel tough at times, but just know that this is the #Universe’s way of sorting out any kinks and making a way for a #better #future for us all."

#fullmoon #partial #lunar-eclipse #astronomy #astrology #taurus #solarsystem #taurusfullmoon #mourning #reed #beaver #frosty #snow #moon #kartik #purnima #planets #stars #earth #sky #cosmos #umbra #penumbra #micromoon #saros #luna #lunar

Full Moon Guide: November - December 2021 – NASA Solar System Exploration

The next full Moon is the Beaver Moon, and there will be a near-total lunar eclipse.

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