9

The Brightest Cluster Galaxy (BCG) in Abell 2261 ("Abell 2261-BCG") is a massive elliptical; these almost always seem to have supermassive black holes in their centers. In addition, the center of the galaxy has a large region of relatively low stellar density (a "core"), something usually thought to be produced by the merger of two SMBHs ...


8

This web page -- "Here is why the Hubble Space Telescope only looked a few times at Venus (and why it looked at the Moon instead)" -- seems like a pretty good answer to your main question (note: "MAST" = Mukulski Archive for Space Telescopes): There are only a few times the Hubble Space Telescope did look to Venus according to MAST. ...


5

I don't think so. In order to resolve an object one metre across (as a single pixel) at a distance of 384,400km (the diameter of the Moon's orbit), you would need a telescope mirror about 200 metres in diameter, and to achieve a resolution of 10cm (which you would probably need to form a recognisable image), you would need a telescope mirror with a 2km ...


4

Physics doesn't require a black hole at the centre of a galaxy, it just indicates that it is likely. All you need is mass. If the mass is not dense enough to form a black hole, it can still be high enough for a galaxy to grow. (Also, finding nothing is not the same as nothing being there. So nobody is ruling out the existence of a black hole there)


2

Neptune has an axial tilt of 28.3 degrees and an orbital period of 164.8 Earth years; currently, the north pole is tilted away from Earth. The maps in your question were each constructed from twelve exposures of Neptune: four each in 845 (red), 547 (green), and 467 nm (blue) wavelengths. Each of the exposures was then converted from an effectively-...


2

If the negative mass is not inside but outside the positive mass, wouldn't it push light passing by away from it, thus towards the positive mass, which would lead to a perceived higher gravitational lensing effect on the positive mass? If so, then https://www.spacetelescope.org/news/heic2016/ could maybe partially explained by negative mass halos on those ...


2

EDIT: I moved the last paragraph to the beginning because it's really a Python question, but I left my "manual" method answer in case it helps, too. Forgot to add this link to Python code on Github. It helped me get started with displaying images using Python and dealing with the headers without altering them. On line 19, I changed it to "...


2

A telescope with that resolution would be extremely expensive. Beyond any sort of reason today. Much of the technology we take for granted was impossible or very difficult when I was born. Back then not many ordinary people had telescopes anywhere the size that are common now. The 200" Palomar was the giant of it's time but today is dwarfed. There have ...


2

I think that somehow that string “M101” got inserted into the search box but has nothing to do with your query results. For example, if you click the “M101” link right below the box it will insert that into the search box without changing your search results until you click “Search”. The images shown in your search output are labeled with their object ...


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