Tag Archives: galaxies

How Do Galaxies Stay Intact?

Question: Do black holes spin? What makes galaxies stay semi organised while precessing around it? I don’t know how else to word that. Physics is hard.  –  Nathan Answer: Yes, it is believed that black holes do spin.  The stars … Continue reading

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What Radio Astronomy Can Be Done at S-Band?

Question: At work, we have a 14 foot dish with an S-Band receiver.  Are there any interesting radio astronomy frequencies around S-Band?  – Frank Answer: The radio astronomy S-band runs from about 2655 to 3352.5 MHz.  Its use in radio … Continue reading

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Why are Andromeda and the Milky Way on a Collision Course Rather than Moving Away from Each Other?

Question: If the universe is expanding and all galaxies are moving away from each other, how is it possible that the Andromeda and milky way galaxies are on a collision course?  – Johnny Answer: It is correct that on the … Continue reading

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What is the Size of the Giant Galaxy IC1101?

Question: I’ve been looking at information about the largest known galaxy, IC 1101. Most sources say it is ~6 million light years in diameter but I can’t find any primary sources for this size estimate. I was looking through research … Continue reading

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The Kerfuffle Over Non-Cosmological Quasar Redshifts

Question:  Some years ago I read an article that said (if I recall correctly) that there were quasars that seemed to be associated with galaxies (maybe in the center), but the quasar’s much larger red shifts implied that their distance … Continue reading

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How Do Astronomers Study How Things Evolve?

Question:  We know that stars and galaxies we see are just fossil light as they were millions or billions of years ago. Is it possible to extrapolate the changes that we see today in those galaxies to determine their current … Continue reading

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What is the Universe Expanding Into?

Question:  Thank you for helping so many people. Is there an educated guess by professionals about the difference between what the universe is expanding into and the universe itself?  – Jay Answer:  This is going to sound very paradoxical, but … Continue reading

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What if a Galaxy had Only One Star?

Question:  What if a galaxy only has 1 sun and 1 planet an it is in the exact middle?  – Lance Answer:  Galaxies are defined as collections of stars (possibly with planets), gas, and dust.  A single sun with a … Continue reading

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Can Gravitationally-Lensed Objects be Studied at Any Wavelength?

Question:  As per definition, Gravitational lensing refers to bending of light rays from a distant source around a massive object (Galaxy cluster) which tends to magnify the background light source. If visible light rays bend around those massive objects then … Continue reading

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Top Achievements for the NRAO Very Large Array

Question:  I’m embarrassed to ask this, as I feel after working here for so long I should already know the answer. But here it is: What are the top 3 discoveries/achievements of the VLA? And why?  — Doug Answer:  As … Continue reading

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