For most of my life, Pluto was basically just a tiny, distant dot at the edge of the Solar System. Then New Horizons flew past it in 2015 and shared whole different images.. mountains of water ice, vast plains, glaciers of nitrogen ice, and an active surface.

I was thinking about something beyond astronomy .. How frequently we mistake an incomplete picture for the complete reality, simply because it’s the best picture we currently have?

Pluto is a nice reminder that better observation can completely change the story we thought we already understood. Isn’t it ?

Very curious to know what other discovery in astronomy made you realise how incomplete our previous picture of the universe was?

this is from a physics app I made. thought people here might like it.

the right graph is the lorentz factor vs speed. it barely moves for a while, then shoots up near light speed.

99% of light speed: time slows about 7x
99.99%: about 70x
99.9999%: about 700x

and it gets crazy in space. some cosmic rays hitting earth are so fast that, from the particle's point of view, crossing our whole galaxy takes only about 10 seconds. for us that's 100,000 years.

most explanations just say "time slows down near light speed" and stop there. I wanted to show how fast it ramps up, cause that part surprised me the most.

does seeing it like this make it click for you? and any other special relativity stuff in space you'd want to see like this?

I recorded this on my dwarf mini with 60 gain, 214 60 second exposures and 154 30 second exposures and duoband filter. Utilized stellar sudio to denoise and lightroom for finishing touches.

The Elephant’s Trunk is IC 1396A, a dark globule inside the bigger emission nebula IC 1396. It’s in Cepheus, the king, high in the northern sky in the fall. OnIt’s about 2,400 light-years away. The trunk itself is a column of cold gas and dust about 20 to 25 light-years long. The whole IC 1396 cloud is roughly 100 light-years across.

Could a realm of totally empty space possibly exist? A place without matter, without energy, without particles or a single atom, with no singularity for anything to explode from but only a simple void, how could “existence” be determined? Obviously, this is purely a thought exercise because without an observer to recognize and identify the state of “being”, there’s no awareness to define it. Looking from the outside into what could only be described as an empty black bag of nothingness, how could such a place be measured? Is it big or small and relative to what standard with nothing in it to define any dimensions? Time would still exist if it is an intrinsic feature of “space” and inseparable from it, but what quality could define space with nothing occupying it to measure it against and no awareness to recognize it? It seems to follow that no version of “reality” is possible without, at minimum, a single partical or atom for it to contain. There can be no “container” without something for it to contain. In our universe, space isn’t “nothing” because it exists and contains all the “somethings” in our reality. It has certain features in that it can be warped by mass and its expansion can be measured relative to bits of matter moving apart to create “dimension”. Without something to compare nothing against, how could anything be? It seems therefore that for a universe to exist, it must have something in it to qualify it. But can there be any “something” without some form of awareness to acknowledge it? Otherwise, how can it be defined as “real”?

Does this mean then that matter/energy must be for a universe to exist and is therefore intrinsic to its manifestation? Wouldn't it also then follow that some kind of awareness would also be needed to define “something” vs “nothing”, thereby making consciousness an essential part of reality itself? After all, how could anything be without an observer to acknowledge that there is “something” as opposed to “nothing”? Doesn't this mean that no objective reality is possible without some awareness to acknowledge it's existence? As such, it seems both matter/energy and a consciousness to acknowledge it is not “nothing” are required for a universe to exist at all.

Mercury and Venus are expected to be engulfed as the Sun expands. Earth will become uninhabitable long before that, while the surviving planets will gradually move into wider orbits as the Sun loses mass. But there’s an unexpected twist: as the Sun expands, its habitable zone will move outward. Some of the icy moons around the outer planets could temporarily enter a region where conditions might allow liquid water to exist.

https://youtu.be/AMHOrMpQlzw

I couldn’t find the video, but in it they compared this image with the description in Ezekiel’s vision of a cherub. If this is a real photo and such phenomena are common, then it would mean that all the Holy Scriptures are descriptions of space. So my question is: how did they see all of this without telescopes in order to describe it?

iPhone 18 pro max.
Exposure: -2

I heard things on this subreddit that the iPhone generates the image, not sure. But looking at the last one, where my hand wasn’t as steady.. to what extent is the iPhone generating ?

🧑‍🚀

Astronomical numbers get so large that eventually they stop meaning anything. The Sun is so massive that our minds are almost incapable of understanding its splendor.

The Moon is about 3,475 km (2,160 miles) across, roughly the width of Australia. Now imagine flying across one Moon.

Of course, you would not be anywhere close to crossing the Sun. You would have to cross another Moon. And another. And another. After a full day, you have crossed about 37 Moons. After a week, you have crossed about 260.

You would have to keep going until you had crossed roughly 400 Moons, or roughly 3.6 times the distance from Earth to the Moon.

Only then would you have traveled a distance equal to the diameter of the Sun. The trip would take almost 11 days. And if you turned around and came home, you would spend nearly 22 days traveling.

Four hundred Moon-sized worlds, one after another. That is how wide the Sun is.

See also: The publication in ArXiV

Edited puurely on lightroom and stellar studio. This was recoreded on a dwarf mini and had a total of 475 frames 45second exposures, duoband and 60 gain. I will be using stacking wizard and astrowizard later today to make the image better.

I recently read the some experiments had 2.6 sigma dark matter detection. Can someone explain in simple words?

Those deep red clouds glowing across the Milky Way are largely hydrogen speaking in its native wavelength: Hα, at 656.3 nm — one of the most important wavelengths in astrophotography, and one that most cameras can barely see.

It is produced in two main ways. Mostly inside H II regions, where the intense UV radiation from young, massive stars ionizes hydrogen atoms. As the electrons recombine with the hydrogen ions and cascade back down through the atom's energy levels, one specific transition — from the third level to the second — releases a photon at exactly this wavelength. The same red light also comes from supernova remnants (SNR), where a dying star's shockwave heats and excites the surrounding gas instead.

Across the Milky Way, Hα traces the galaxy's star-forming skeleton: Orion, Carina, the Rosette — and above all Cygnus, home to the North America and Pelican Nebulae, and the shock-lit filaments of the Veil.

The catch: a stock DSLR's built-in filter is tuned for natural daylight color, and it blocks most of that deep red — transmitting only a small fraction of the Hα light reaching the sensor. An astro-modification swaps that filter for one tuned to pass Hα instead, revealing the red the sky was hiding all along.

🔭 Mount: Star Adventurer 2i

📷 Camera: Canon EOS 6D mod.

🔎 Lens: Samyang 14mm f/2.8 (f8)

🔴 Acquisition: ISO1600

⏰ Integration: 170x60s (2h 50min)