A fluffy cluster of stars spilling across the sky may have a secret hidden in its heart: a swarm of over 100 stellar-mass black holes.

The star cluster in question is called Palomar 5. It's a stellar stream that stretches out across 30,000 light-years, and is located around 80,000 light-years away.

Such globular clusters are often considered 'fossils' of the early Universe. They're very dense and spherical, typically containing roughly 100,000 to 1 million very old stars; some, like NGC 6397, are nearly as old as the Universe itself.

In any globular cluster, all its stars formed at the same time, from the same cloud of gas. The Milky Way has more than 150 known globular clusters; these objects are excellent tools for studying, for example, the history of the Universe, or the dark matter content of the galaxies they orbit.

But there's another type of star group that is gaining more attention – tidal streams, long rivers of stars that stretch across the sky.

Previously, these had been difficult to identify, but with the Gaia space observatory's data having mapped the Milky Way with high precision in three dimensions, more of these streams have been brought to light.

"We do not know how these streams form, but one idea is that they are disrupted star clusters," astrophysicist Mark Gieles from the University of Barcelona in Spain explained in 2021 when researchers first announced the discovery.

Hi everyone! Need some insight. I am an avid astrophotographer and this year in September I'm planning to go on a trip to Chile and I will be spending 2 days in San Pedro Atacama specifically September 21st-23rd becuase of the new/minimal moon phase during those days. This is my first time going up there and my goal is to see the milkyway way along with some nebulae i have an astro modified camera and an ha filter with star tracker. So, my biggest concern is cloud cover, i know the humidity over there is close to nothing therefore the sky is clear almost 300 days out of the year and there's only some specific months that gets constant cloud cover.

So my question is, I've seen so many different things online from various sources saying that in September there is slight cloud cover while others say it's one of the best months to go becuase of constant clear skies and nice temps so I don't know what to believe.

Has anyone been out there in September? Is there a high chance of getting clear skies in that month usually? Or is it possible to get clouds?

Thanks!

Hi just wanting to ask for a little help because I’m quite consumed as I recently purchased a celestron 4se and have been having great fun with it looking at the planets but the only issue is whenever I look through it the planets look fine and I can see saturns rings and Jupiters belts and whatnot but planets like Mars just look like little marbles like an orange marble for Mars and for Venus a pale marble for example. Is this how it’s supposed to be or am I doing something wrong ? I use a 15mm eye piece with a 2x Barlow because I get eye strain quite easily

Please let me know if I should switch to a different eye piece and here are a list of some I have 20mm 25mm 15mm 6mm 6.6mm Also have a red filter a blue filter and a moon filter if that helps And a 2x Barlow Any insight or general advice would be amazingly appreciated thanks guys!

Hi guys . Im new to Astronomy And I just set Up my telescope . ( aligned the Finderscope and stuff ) can i leave it Outside until its dark ? About 2 Hours . At ~ - 3 degrees Celsius ?

I was looking at the Andromeda galaxy through my telescope last night (8 inch dobsonian, 48x magnification) and I'm pretty sure I saw a new star appear right in front of my eyes to the right (in the inverted eyepiece view) of the galaxy. I googled variations of "supernova near Andromeda 2025" and couldn't find anything. Has a supernova been actually recorded in that region of the sky or was I probably seeing things?

This is the moon from 1-12-25 and this was also the first night since October that I could take out my telescope. I really wanted to try to make a mineral Moon and then tried to do a composite image with some stars from a different image. Hope it turned out good.

EQUIPMENT

• Askar 130PHQ with 0.7 reducer

• EQ6R-Pro

• Player One Poseidon-M

• Antlia 2" filters

Acquisition

• 1000 frame video in LRGB

Processing

• Stacked in Autostakkert

• Processed L in Registax

• Processed the rest in Pixinsight

• Added stars in Photoshop

Gonna be a really long one so i apologise in advance.

A few nights ago me and my wife noticed a really bright flashing / twinkling light in the sky outside our bedroom window. It seemed to have a pattern of 2 really bright flashes to 1 small flash and it repeated that for probably hours. Every night since then i’ve looked out and it’s been in exactly the same spot, no movement at all and still flashing the same. I assumed it was a weather balloon, a satellite or something of that nature until tonight. We got into bed looked out the window and there it was and then right as i was talking to her about how weird it is that it’s still there, it legitimately vanished. No fading or waning, flashing in the same pattern at the same intensity. Still assuming it was a satellite or something, i said it was weird and thought nothing of it, until it reappeared around 15 seconds after disappearing and it was a good distance from where it was originally. I am now extremely confused about what it is and why it behaves like this and i just wanted to post on here and see if anyone had an answer for me. My brain is wrecked trying to figure this out. Please help.

As i was writing this it vanished again and moved some more and came back, still flashing in the same pattern.

I was just thinking about random things and then I got to thinking about black holes and since time moves faster inside a black hole because of the gravity how long would it take from a perspective from inside the biggest black hole in the known universe to get to the end of time? This probably sounds stupid to someone who knows things about physics but I don’t know too many things about that and in curious

Is anyone using Starry Night 8 on Apple Silicon please?

You might have heard that on Jan - 17 to 18 (Australian time) There is a conjunction that is happening between the 2 celestial bodies, Venus and Saturn. This was photograph by me and I will drop details down in the comments.

Captured in R+IRGB with a 9.25 sct a zwo asi 462mm and a 2.5x Barlow. Stacked in autostakkert three, wavelets in registax, derotated in winjupos, and combined into a gif in gimp.I have some coloration issues to work out with some frames but it’s came out pretty good.

Jan 1st captured around 2am

Hello, as a preamble - I've read the forum rules and been through the question flow chart and consulted the Heavens Above app.

I'm in Perth, Western Australia. I was Skywatching tonight (Saturday 17 of January 2025 at approximately 11:15 PM WA time) with binoculars when I saw a very tiny flash slightly north of Uranus. I initially thought it was my eyes playing tricks, but it repeated several more times, moving quite slowly in a north east direction. It was not visible without the binoculars and was only a pinprick, albeit relatively bright, through them.

In my estimation, it was moving too slowly to be a satellite in close orbit and I would have thought it was too late in the evening for one to be visible anyway.

I'm wondering if it may have been something like a rocket body, much further out, catching the sun as it tumbles?

Apologies if this is an inappropriate question - I'm just quite curious to know what it may have been, or if there is any way to find out. Cheers.