Astronomy

cross-posted from: https://rss.ponder.cat/post/16484

I just wrote this article and I would like your comment:

The Universe Will Not Die a Heat Death

We assume that the universe is expanding according to the Lambda-CDM model with a fixed Lambda constant.

Imagine a central star, like our sun. Two artificial satellites are orbiting this sun in circular orbits in opposite directions. As the universe expands, the orbits of the satellites are elevated, and the satellites thus gain mechanical energy (the sum of potential and kinetic energy). This energy can be released by causing the satellites to collide or by simply having them graze each other. As a result, some of their kinetic energy is converted into heat, which can be radiated away as thermal radiation, and the satellites descend to lower, more inward orbits. The process can then begin anew.

Source

Big bang doesn't explain

1. The axis of evil
2. Observable galaxy formation earlier than predicted
3. Red lights as seen from JWST should be SMBHs except that big bang theory doesn't predict

Big bang is just wrong.

As always with these news it is still too early to draw conclusions: more analysis and tests are necessary.

https://www.nasa.gov/missions/mars-2020-perseverance/perseverance-rover/nasas-perseverance-rover-scientists-find-intriguing-mars-rock/

I was about 30 years old when I talked to my mother about some program on TV about astronomy when she mentioned that our sun is a star. It's like all the other stars we see during the night, it's just closer to us so it appears bigger. My mind was blown. I didn't understand how I could have lived for 30 years and never thought this thought.

Yesterday me and our 10 years old were talking about the universe and things in it, and I mentioned to her that our sun is just a star like all the other ones we see during the night. I saw that her mind was as blown as mine was back when my mom told me this fact.

Actually even in the song "Twinkle twinkle little star, how I wonder what you are." it encourages us to think about this fact, but it took me 30 years to do so.

A group of astronomers want to change the definition of a planet. Their new proposed definition wouldn't bring Pluto back into the planetary fold, but it could reclassify thousands of celestial bodies across the universe. From a report:

The International Astronomical Union's (IAU) current definition of a planet, established in 2006, includes only celestial bodies that are nearly round, are gravitationally dominant and orbit our Sun. This Sun-centric definition excludes all of the bodies we've discovered outside our solar system, even if they may fit all other parameters. They are instead considered exoplanets. Those behind the new proposal critiqued the IAU's definition in an upcoming paper in the Planetary Science Journal, arguing it's vague, not quantitative and unnecessarily exclusionary.

Their new proposal would instead classify planets based on their mass, considering a planet to be any celestial body that:

1. orbits one or more stars, brown dwarfs or stellar remnants and,
2. is more massive than 10ÂÂ kilograms (kg) and,
3. is less massive than 13 Jupiter masses (2.5 X 10^28Âkg).

The planet Jupiter is particularly known for its so-called Great Red Spot, a swirling vortex in the gas giant's atmosphere that has been around since at least 1831. But how it formed and how old it is remain matters of debate. Astronomers in the 1600s, including Giovanni Cassini, also reported a similar spot in their observations of Jupiter that they dubbed the "Permanent Spot." This prompted scientists to question whether the spot Cassini observed is the same one we see today. We now have an answer to that question: The spots are not the same, according to a new paper published in the journal Geophysical Research Letters.

From the other place: https://www.reddit.com/r/space/comments/1dmibwd/this_is_my_most_advance_moon_photograph_ever_it/

Pics too good to miss. :)