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Q & A: General Astronomy and Space Science

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Astrophysics   Astronomy (def.): Branch of science dedicated to the study of everything in the universe that lies above Earth's atmosphere.

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Q: Do you have any images or data that show that there is a discrepancy in location of any objects (especially galaxies) between X-Rays and optical/radio wavelengths?

Q: When will the Local Group of Galaxies fall into and join the Virgo cluster?

Q: What is " molecular gas" ? How is it different from regular gas?

Q: What keeps electrons moving? Why don't they slow down?

Q: As the planet Earth is accumulating meteoric dusts in tons every day, will not the mass of the Earth increase? If so, does it affect its spin? Does the gravity get affected?

Q: If sound and images from early radio and television left Earth, would it be possible to pick up the signals in the distant outer space of the Universe?

Q: What do the initials of "OBAFGKM" mean?

Q: How old is the Moon?

Q: What is the life cycle of a star and how old can one get to be?

Q: What are the different types of EMR and what are they used for?

Q: The farther away from a sun that you get, would there not be vast reaches of space that would never receive even one ray of light from a sun?

Q: At what distance, position and angle are we from the galactic plane?

Q: My understanding is that cosmic rays are made of protons and atomic nuclei which collide and form other particles, giving off some photons in the process, and that photon does not slow down to become anything else (the decrease in the frequency of a photon is not the same as the decrease in speed) and its existence as far as is now known is independent of other bosons and leptons. Can you confirm either notion?

Q: Could you explain what nucleosynthesis is?

Q: I have never heard of any one mentioning gamma rays. Do gamma rays exist in space?

Q: Do the all sky maps represent a maximum distance for the surface of a sphere, and does this sphere represent a look at the sphere from a vantage point outside the surface of the sphere?

Q: There was a bright flash of light in the southern sky with some smaller lights (debris?) and I was curious what it might have been.

Q: In many articles on astrophysics I have come accross the term space-time quite often. What does it actually mean?

Q: Why can't we see the autumn constellations in the night sky in the spring?

Q: How fast do gravitational waves travel?

Q: How long would it take for scientists to notice the effects of the NGC 6240 merger in our galaxy and/or in other galaxies?

Q: Why is our galaxy called the milky way?

Q: If light travels to us from the Sun at 186,000 miles per second and takes 8 minutes, does that mean if I stood 100,000 miles from someone and then switched on a torch they would see it just after I switched it on?

Q: Aren't stars and galaxies are so far away they are regarded as point sources? Then how can that trigonometry be practised?

Q: All the stars and galaxies move, so how sure are we to say that the Crab Nebula is moving at X km/sec in direction Y?

Q: Is our solar system moving or travelling within our galaxy? Is our galaxy travelling or moving in the universe? If so, how fast?

Q: What is the look-back time?

Q: What are the different frequencies of light in the spectrum (such as X-rays)?

Q: Where do Giant Molecular Clouds come from?

Q: Why is that for 1 parsec such an odd value has been chosen (i.e. 3.26 light years)?

Q: Is the Earth really slowing?

Q: Why is time influenced by gravity?

Q: (1) How do you know what a particular star's light would look like without the shift, so that you can calculate how much shift has occurred, and then the star's distance and velocity? (2) Do not visible portions of the electromagnetic spectrum, for example microwave and X-rays, also exhibit a "red shift"type of phenomenon? If so, what do you call and how do you measure this?

Q: Do falling stars really exist?

Q: Do you have a data table from which the electromagnetic spectrum illustration was made?

Q: Where can I find information of Canis Major (the constellation), its history, and the history of its 3 brightest stars?

Q: Why does the star Sirius sometimes appear to change colors rapidly, red-green-white, several times per second?

Q: For four nights in a row (Nov. 2001) I've seen a falling star. Each star seems to follow the same path and all have been around 9:30 and 10:00pm. Does that mean anything special?

Q: Saying that the prime meridian passes through the galactic pole does not seem very specific to me. Is it not necessary to specify at least one more direction (point on the celestial sphere) to locate a meridian?

Q: Could you please explain why the word INERTIAL is used in "Inertial Upper Stage booster"?

Q: Is it possible to travel into the future by traveling the speed of light around the Earth for an entire year inside a spaceship that is going the speed of light?

Q: Looking at the real-time satellite tracking applet, I noticed that with a couple of exceptions it appears that every satellite you list, including Chandra appears in one of two basic orbital shells. One of these being very close to the Earth, and the other being somewhat farther away.

Q: I just watched a program on space which quoted that for every grain of sand on the Earth there are a million stars in space. Is this true, and if so, how do we know this?

Q: Does a red giant appear red from the surface of the Earth? If not what does one need to see a red giant?

Q: Is there a technical difference between a spacecraft vs. satellite? eg, all spacecraft can be satellites but not all satellites can be spacecrafts?

Q: What are light years and why are they used in astronomy?

Q: During stellar gravitational collapse, what could be the impact generated by the variation of gravitational forces on the space fabric?

Q: I am interested in selecting a telescope. Where does a novice begin? Any books that you could recommend? My interest has been sparked by the pictures from Chandra and Hubble.

Q: Where did the energy come from that caused the newly created Earth to be in a molten state?

Q: Could you send me some information regarding the history of Astronomy and particularly about the various missions that span the electromagnetic spectrum?

Q: I would like to have some information on how the Two States of Plasma and Bose-Einstein Condensation works, and what are its properties.

Q: Which theory of gravitation is correct, Einstein's theory that gravity is a property of space and time, or Newton's theory of gravitation? Could Chandra help us in any way to resolve the above?

Q: Someone once said : "Time and space are modes by which we think and not a condition in which we live." I did not get exactly what it meant. Can you help me?

Q: I have been thinking about the nature of spatial distortion due to matter. If space is distorted are there any other noticeable effects apart from a gravitational field?

Q: I would like to know what the order of the spectrum would look like if we looked at a light made of neon by using a telescope or some other instrument.

Q: Why are stars and planets round but asteroids aren't?

Q: Every picture of a spiral galaxy including our own, depicts a very bright, spherical center...I assume a dense cluster of stars. We can see this bright center in distant galaxies, and I've always wondered, why we don't see the bright center of our own.

Q: Can you explain other space probes that are going into to space soon or are in the blue print stage?

Q: What is going on out there? Are we perhaps living at the speed of light? Is motion of exploding stars visible by the Chandra telescope? All photos of celestial objects I have seen depict objects as stationary.

Q: Where can I find information about meteors and asteroids? I would like to be able to find some for myself, but I can't find any information on scatterfields.

Q: I read in Time Magazine that an asteroid was found recently (I believe it was named AN10) and that it would come within 20,000 miles of Earth in the year 2022. Do you have any information on this asteroid?

Q: How many years is the Hubble telescope scheduled to be in operation, and what is next. Hubble can see 11 billion light years into the known far will the next telescope reach?

Q: I still don't understand the fact that all that photos show something expanding in a "circular/planar" situation and not in a "spherical/3D" configuration.

Q&A Index