Starship Asterisk*

There are some modifications of gravity that could potentially explain both Dark Matter and Dark Energy, that would tiidy things up very nicely. Interesting. It was my understanding that the concept of 'Dark Matter' was invoked to explain anomalously high orbital velocities of stars on the peripher...

I don't think I would classify R136 as a "sexy object". :shock: My first impression of R136 is the extreme brightness of the core of the star cluster, suggesting that stars in the core may be very close together. However, this object is 170,000 ly distant, so that light from these stars wi...

If, indeed, this asteroid may someday impact the Earth (as postulated in the APOD commentary) then we definitely have our work cut out for us in deflecting its orbit. These Earth-crossing "rubble piles" present an insuperable problem at our current level of technology to deflect them while...

I have to wonder if it's the presence of large amounts of interstellar gas that leads to the structure of spiral galaxies. Sounds good to me! :wink: If you can figure out how spiral galaxys form I imagine that astronomers would be interested. Right now I'm not sure that anyone has a clue. Elliptica...

It is likely that the night sky on a planet orbiting a star in a globular cluster would be pretty spectacular because of the clarity. There would be very little interstellar dust and gas to impede your view. But as to the light pollution question; don't forget that stars would be separated by vast d...

Hi nikki, I goofed in my original calculation for the average distance between stars in the globular cluster, NGC 5139: :roll: With a diameter of 150 ly, the GC has a volume of 1.77 million cubic ly (a sphere) containing 10 million stars. Assuming each star occupies the center of a spherical volume ...

Thanks astro_uk. Very enlightening. As I understand it, all galaxys appear to have super-massive black holes at their cores, whereas globular clusters do not. If the precursor to galaxy formation was the presence of a SMBH, what if anything was the precursor to the formation of a globular cluster? M...

Actually this post refers to all globular clusters orbiting the Milky Way galaxy. My question: If the Milky Way galaxy is embedded is a much larger cloud of Dark Matter, should not the orbits of all globular clusters be affected? That is, shouldn't the orbits be different if there was no Dark Matter?