X-rays detected by the Chandra X-ray Observatory expose a wealth of exotic objects and high-energy features. In this image, pink represents lower energy X-rays and blue indicates higher energy. Hundreds of small dots show emission from material around black holes and other dense stellar objects. A supermassive black hole – some four million times more massive than the Sun – resides within the bright region in the lower right. The diffuse X-ray light comes from gas heated to millions of degrees by outflows from the supermassive black hole, winds from giant stars, and stellar explosions. This central region is the most energetic place in our galaxy.
Credit: NASA, CXC, D. Wang (University of Massachusetts, Amherst, USA) and STScI
How much mass do flocculent spirals hide? The featured true color image of flocculent spiral galaxy NGC 4414 was taken with the Hubble Space Telescope to help answer this question. The featured image was augmented with data from the Sloan Digital Sky Survey (SDSS). Flocculent spirals -- galaxies without well-defined spiral arms -- are a quite common form of galaxy, and NGC 4414 is one of the closest. Stars and gas near the visible edge of spiral galaxies orbit the center so fast that the gravity from a large amount of unseen dark matter must be present to hold them together. Understanding the matter and dark matter distribution of NGC 4414 helps humanity calibrate the rest of the galaxy and, by deduction, flocculent spirals in general. Further, calibrating the distance to NGC 4414 helps humanity calibrate the cosmological distance scale of the entire visible universe.
Here's a shot I took over a decade ago using a self-made Sun filter which I temporarily mounted on the eyepiece of my 2,5" telescope.
For safety reasons I'm not going to reveal any instructions. The filter was very sensitive and unreliable. My previous attempts all failed because the filter burst into 🔥🔥 within seconds due to wrong positioning on the eyepiece (just few mm off), so I had to recreate it several times.
To my surprise, when I looked through the filter with a naked eye I was able to distinguish a couple Sun spots that the camera failed to capture.
The picture was taken by aligning (the ancient) SE W960i on the filter :) Do not attempt anything similar at home! Save some money and get yourself a decent stand-alone solar telescope for a jaw dropping experience. Want to see some examples ? Check this guy out @timm1138