Photograph via snooOG

The amateur hobby of humanity since the dawn of time and scientific study of celestial objects.

Everything to do with Astronomy

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"Astronomy compels the soul to look upward, and leads us from this world to another."

"We are a way for the cosmos to know itself."

Answers to Common Questions

How do I Become an Astronomer/What do Astronomers Do?

What telescope/accessories should I buy?

What should I look for in the sky?

What Was That Bright Moving Object I Saw?

Where Can I Learn About Astronomy?

Can I Get Help With Homework?

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What has the earth been around to see?

I just learned there was a man called Samuel J. Seymour who shared his lifetime with both the American civil war and Brian Cranston. I thought that this man is an incredible testament to just how 'big' time is, at least on a human scale. But what about a cosmic scale? I also recently learned that the Earth was around before Saturn had rings, and that got me wondering. I want to know, what are some cosmic events that happened between now and the forming of the Earth?

16:48 UTC


Bennu Sample Analysis

The team analyzing the asteroid sample returned last September has published, and it’s available free online https://onlinelibrary.wiley.com/doi/10.1111/maps.14227

The sample dropped by OSIRIS-REx arrived intact on the Utah desert floor in its sealed canister and was transported to its special clean room, carefully sealed inside a glove box that’s constantly purged with pure nitrogen. The intricate, painstaking care taken at every step to ensure the sample remains uncontaminated is itself fascinating.

“…the canister was opened on September 26, 2023…

“In the weeks that followed, curation scientists and technicians embarked on the delicate task of disassembling the TAGSAM head… Two of the 35 fasteners securing the TAGSAM head could not be unscrewed using the approved tools available in the glovebox…

“In mid-January 2024, the curation team successfully removed the two stuck fasteners using a custom tool… “

It took 4 months to open the inner canister! Science is slow, painstaking work…

The first step was visual analysis and photography. Again, careful to the Nth degree:

“The Advanced Imaging and Visualization of Astromaterials (AIVA) procedure was used for comprehensive imaging to document the condition of the hardware upon arrival, the disassembly process, and the visual characteristics of the sample…

“…we use a medium-format camera system with a full-frame 102-megapixel sensor and a variety of lenses. The sample remains inside its glovebox, which is constructed from highly reflective materials, and all camera and lighting equipment are positioned outside the glovebox. This setup limits our range of motion around the sample, requiring us to essentially perform macro photography at telephoto distances through small glass windows into a mirrored box… “

A first step in analysis is determining and recording the sample particle distribution size, from stones on down, with mathematical precision. This involved counting and measuring 7154 particles.

I find this work endlessly fascinating, and a reminder that there are very few “Eureka!” moments in science. Analysis of this precious 120 grams of pristine carbonaceous regolith from Bennu will take years, and the information it yields may reward us for decades.

14:34 UTC


NGC 3726 - Barred Spiral Galaxy

13:45 UTC


Accurate star projector

Hello there!

I recently got into my own new place and I'd love to have Astronomy themed decor. Following that idea, I've been looking to get a star projector that is -more or less- accurate but I couldn't find anything other than "nebula-ish projection" on the internet, could you crazy people have soms links to find such an artifact?

Thanks in advance!

1 Comment
11:08 UTC


The Tiangong Space Station Solar Transit through a Hydrogen Alpha telescope

06:00 UTC


Where did you see the most stars?

Which national park in the USA did you see the most stars?

02:43 UTC


Animation of the Ptolemaic universe

23:48 UTC


Pillars of Creation in M16

19:42 UTC


Is it possible for a brown dwarf to form a sub-system inside of a Solar system?


title. I made a scetch, theyellow dot is the sun and the brown dot is the brown dwarf. the blue dots are the planets around the sun and the purple dots are the planets of the brown dwarf. Or would these bodies be called moons? afaik brwons dwarfs are neither planets nor suns, so i’m not sure what the correct term is. Also, can the planets from the brown dwarf have moons (green)? If yes, does that mean, that there is a sub-system (orange) inside the solar system (red)? And an other questions is, do brown dwarf have a habitable zone? so could a planet in the sub-system have the potential to spawn life?

19:40 UTC


Losing some of my energy for astronomy with my eyes starting to age

Astronomy makes me empathize with folks who have needed glasses or other vision enhancements for their astro hobby (or really anything that requires use of lenses - from VR to Photography to Astronomy to you name it).
As my eyes get older, I start to wrestle with whether I get lasik or lens replacement or something now that I need glasses to correct for a developed astigmatism and focus. What experiences do you have with this?

17:26 UTC


Best Way to View Andromeda?

I recently got my Skywatcher 200P out after having not used it for quite some time and attempted to take a look toward Andromeda as the conditions were very good.

I’m pretty sure I did see it, however it just looked like a blurry smudge in the lens and I was unable to get it in focus, I have a 10mm, 25mm eyepiece and a 2x Barlow lens, I tried all combinations with and without the Barlow (I was unable to locate it all using the Barlow) however I was still unable to get it in focus.

Is this due to the conditions not being good enough or is my setup incorrect?

I really want to try and start looking for more deep space stuff, planets and the moon are obviously very easy to find and focus on, but without a GoTo mount deep space stuff is obviously much harder, even more so if I’m unable to get an actual focus on something once I find it.

Are there any upgrades besides a GoTo mount that would make my life easier?

15:20 UTC


Binary stars: apparent visual orbit vs real orbit plotting

I'm struggling to find real plots of binary stars, where by "real" I mean the opposite of apparent, i.e. hypothesized/deduced/reconstructed. I thought I could find one for 70 Ophiuchi, which has a short apparent period of 88 years but all I can find is the visual plotting. Anybody knows any valid online/editorial reference?

13:08 UTC


Rosette Nebula aka Skull.

12:51 UTC


Interstellar question

I don’t know how scientifically accurate Interstellar is. I know there are definitely some things that are not true but there are some things that are accurate? Anyway, could someone explain to me in the simplest way possible the concept of time difference and how when they went to one of the planets it was 7 years for each hour? Is there science behind that? I am very intrigued to know and don’t know how to search it up.

04:14 UTC


Why isn't the moon and stars in the night sky perceived as yellow, when the atmosphere makes it so our sun is?

How come the blue light gets scattered at day, making the sun more yellow (and the sky blue?), but at night the stars and moon look white?

Is it a lack of contrast? What is it? Hilfen bitte

20:04 UTC


when a star dies what happens to its energy when there is nothing left in the universe for example after the black hole era?

ive read somwhere that the energy we are made out of will be recycled back up into the starts but not sure if this is ture or not. however my main question is what happends to said energy when the star dies does the energy just float around space endlessly or does it serve another purpose?

I got this idea from this page https://futurism.com/the-physics-of-death

don't know if what they are saying is fact or fake though

16:34 UTC


what is the safe distance from the sun to point a 8 inch dobson at?

i want to look at the moon during the day but im wondering how far would it have to be from the sun for it to not burn out my eyes

14:27 UTC


Career path

I am currently doing my masters degree in mechanical engineering (focus on fluid dynamics and simulation methods) however i am not really satisfied by my field anymore. For about 1 and a half years i'm really into cosmology and large scale cosmic simulations like the Flamingo project and i would rather do something like this than working for a large tech company after i'm done with my degree. I really unsure what the best way is to transfer into cosmology without having to do 5 years of university again basically starting all over. Would you see any possibility to work at a university insitute for astrophysics without an astrophysics degree but rather with extra credits in the necesssary subjects or something else? or should i just finish my current degree and do another masters in physics with a following phd in the specific field? thank your for any input!

1 Comment
10:01 UTC


Unable to polar align.... Where am I going wrong?

I'm at my wits end trying to figure out where I am going wrong.

My Setup:

Sky watcher HEQ5- Pro, SVBONY S503, ZWO OAG, ZWO ASI294MC, ASI Air Pro

I am relatively new to astrophotography, I have installed an OAG between the telescope and the ASI 294MC. I ensured that the tripod is leveled, balanced the telescope on the mount by adjusting the counter weight. Changed the setting in asiair to match the guide scope focal length to the telescope FL.

After polar alignment (southern hemisphere) I start shooting but I'm getting blurry images despite of using bahtinov mask. The RA is off by 30-40" whereas Dec is between 0.8-1.3".

I stop the shoot, go back to polar align and its off again. Repeat the whole process but I am stuck in a same cycle, to the point I just want to give up on this hobby

09:02 UTC


Map the prime meridian centered or left edge on planetary maps ?

I have searched JPL and the IAU materials for any official standard for placement of the Prime meridian on planetary maps. There seem to be two choices; centered, or left edge. I am writing some display software and I am at the point where I must make a choice. Can anyone point me towards the appropriate governing body and a reference I can cite ?

22:55 UTC

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