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Astronomy/Questions Answered by Expert James Gort
| Subject | Date Asked |
| entanglement | 12/15/2011 |
| Q: I have just read the following 2 books: 'Imagining the Tenth Dimension' by Rob Bryanton, 2006 and ... A: Sorry - I forgot to include the link to Prof. Susskind's videos - ... | |
| entanglement | 12/14/2011 |
| Q: I have just read the following 2 books: 'Imagining the Tenth Dimension' by Rob Bryanton, 2006 and ... A: Let me preface my remarks with the comment that my research has not included the "early universe" ... | |
| Things to do on a budget..... | 11/12/2011 |
| Q: Several of my friends and I have a lot of interest in astronomy and wish to get into backyard ... A: Yes, indeed there is! But let me first say that one of the most important things you can do (IMHO) ... | |
| What would happen to the earth if an asteriod hit the moon? | 10/16/2011 |
| Q: What would happen to the earth if an asteroid hit the moon? Would we as people be affected. Would ... A: A lot depends on the size of the asteroid. If it had enough mass to eject material beyond the ... | |
| Supernova | 10/15/2011 |
| Q: Gort, I recently saw an astronomy documentary about supernovas, and they said that Betelgeuse--one ... A: You've asked a very interesting question, and one in which there has been some research, but no ... | |
| light | 10/2/2011 |
| Q: I Have some questions related to light. They are stimulated from the recent 'alleged' speed of ... A: You're right - you didn't ask WHY they have the speed they do, but you ask about their "creation" - ... | |
| light | 10/2/2011 |
| Q: I Have some questions related to light. They are stimulated from the recent 'alleged' speed of ... A: I'll do my best to answer the question. But the "why" question you ask - why neutrinos have the ... | |
| Star formation | 9/27/2011 |
| Q: I have a hypothetical question. Ok lets start with a large 1st generation star. Now lets say that ... A: Interesting hypothetical situation. Although your assumption that a second generation star needs a ... | |
| Science Fair Project dealing with Yarkovsky Effect | 9/20/2011 |
| Q: My name is Matt. I'm in the 8th grade and I'm working on a science fair project this year that ... A: Just a suggestion. I think this is still a good idea, but keep in mind that results will be ... | |
| Why I doubt vising aliens exist | 8/24/2011 |
| Q: There are a lot of articles at the moment regarding whether aliens have, or do, visit planet Earth. ... A: I certainly understand your reasoning, and others (including many scientists) have made similar ... | |
| BIG BANG | 8/20/2011 |
| Q: i was watching this documentary on BIG BANG on discovery channel and there i heard a couple of ... A: You've asked a lot a important questions. And no matter what you've heard, astrophysicists don't ... | |
| Satellites | 8/7/2011 |
| Q: If you can not answer this question maybe you know someone who can. I used to frequent J Track at ... A: Apparently, NASA, specifically Marshall Space Flight Center, has restricted access to J-Track and ... | |
| The creation of the Universe | 8/1/2011 |
| Q: During hundreds of years scientists have been concerned about how the Universe was created. ... A: The issue of religion (or lack therof) has no bearing on the answer. The difference between a ... | |
| The creation of the Universe | 7/31/2011 |
| Q: During hundreds of years scientists have been concerned about how the Universe was created. ... A: First, although I'm an astronomer (actually, an astrophysicist), I am not so arrogant as to think I ... | |
| Can Pulsars be seen from Earth without Telescopes? | 7/29/2011 |
| Q: I'm a bit confused whther pulsars can be seen with the naked eye or not. This site says no ... A: M., No known pulsars can be seen with the naked eye. But, of course, they can be "seen" from earth ... | |
| Elliptical Orbits | 7/21/2011 |
| Q: Why all the planets and stars revolve around everything in an elliptical orbit rather circular? If ... A: First of all, I want to remind you that the origin of the universe by a "Big Bang" is very much ... | |
| How far can we see | 7/20/2011 |
| Q: An article in the current Scientific American says that we can see out to 42 billion light years. ... A: A "good" explanation can be found at http://en.wikipedia.org/wiki/Observable_universe. That wiki ... | |
| Habitable planets | 7/15/2011 |
| Q: I have been using the build your own solar system gimmick on this website:- ... A: I agree with you. A few things don't seem right. If you put Earth's characteristics in the model, ... | |
| evolving stars? | 1/11/2011 |
| Q: just for the record I am an sixth day creationist I humbly do not believe the macro-evolution or big ... A: First, let me be on record that I have an open mind about the big bang. My personal view is that ... | |
| Hubble equation | 1/10/2011 |
| Q: I am reading an astronomy text and have come across what appears to be a contradiction, and I ... A: Because relativity is involved, it's not straightforward. You probably are aware of this page, but ... | |
| Hubble equation | 1/9/2011 |
| Q: I am reading an astronomy text and have come across what appears to be a contradiction, and I ... A: Interesting question. First of all, I want to remind you that the origin of the universe by a "Big ... | |
| Quantized Red Shift | 1/2/2011 |
| Q: I have been reading on the quantized red shift discovered by William Tifft in the 70s. From what ... A: First, I don't think that the Tifft quantization of redshift is widely accepted. I believe that ... | |
| career guidance | 4/30/2010 |
| Q: Sir,I'm Genny from India.I'm in 10th standard now.I have a great passion towards astronomy and would ... A: I am glad to hear of your interest and passion for astronomy. To me, that is the main ingredient ... | |
| universe etc! | 4/29/2010 |
| Q: i thought you answered my last question informatively without being belittling so i wondered if you ... A: That's actually an interesting idea, but maybe I can suggest a few things to help it along. First, ... | |
| rotation | 4/27/2010 |
| Q: i am not sure if this has any significance or not but i imagine it might. as we look in on the sun ... A: This is definitely not a simplistic question. In fact, it's probably one of the most ... | |
| Seeing the milky way. | 4/25/2010 |
| Q: How do we know what the milky way galaxy actually looks like? Are the images we have of it only ... A: Since we're inside the Milky Way, the only way we "know" what it looks like is by mapping the stars ... | |
| A Problem/Observation About the Big Bang | 4/24/2010 |
| Q: Mr. James Gort, First, I would like to say that I lack any college level education in on the subject ... A: First of all, I want to remind you that the origin of the universe by a "Big Bang" is very much ... | |
| about Moon | 4/23/2010 |
| Q: ####What's the true shape of Moon's path traveled FOR ONE SYNODIC MONTH around the Earth (according ... A: Merci Beaucoup, Edd, Just compute the velocity of the moon due to its motion around the earth and ... | |
| anti matter | 4/19/2010 |
| Q: it was very helpful. Just one more question please that arose on reading your answer. Can any of the ... A: Just a follow-up and a suggestion. Get the book "Antimatter" by Frank Close. It's a small ... | |
| anti-matter | 4/15/2010 |
| Q: Sir, i would like to know a bit about anti-matter. Is it speculated that other areas of the ... A: Yes, there may be entire anti-matter galaxies, and the physics of star formation, black hole ... | |
| The Early Universe | 4/11/2010 |
| Q: If the images we are able to take now of the early universe are how it looked billions of years ago, ... A: The early universe looks very much like the present universe. To a very large degree, the universe ... | |
| space | 4/10/2010 |
| Q: optimistic values for the terms in the Drake Equation particularly for L, will give a large N, ... A: This sounds like a homework question. Hope it isn't, because I'll answer it. Here are three ... | |
| entropy | 4/3/2010 |
| Q: James, Thank you VERY much for your answer, it was VERY helpful, and I have just order the Kip ... A: I just want to understand your question properly. If the cold object enters the hot universe, and ... | |
| Planetary Alignment 2012 | 1/7/2010 |
| Q: How many planets are expected to line up in 2012? A: There is no unusual planetary alignment in 2012. The most "interesting" alignment will be a transit ... | |
| Supernova effect | 1/6/2010 |
| Q: There was some mention in the media about a supernova, T Pyxidis, being about to blow up any time ... A: That's a really interesting question! I'm going to go through a "back of the envelope" calculation, ... | |
| Effect of a GRB On The Sun at The Peak of Its 'Sun-Spot' Cycle | 1/2/2010 |
| Q: What would be the effect on the sun (if any) if a powerful gamma-ray burst were to hit it directly, ... A: I might stick my head out a little, but I'd say that the sun could, given your GRB scenario, produce ... | |
| Effect of a GRB On The Sun at The Peak of Its 'Sun-Spot' Cycle | 1/2/2010 |
| Q: What would be the effect on the sun (if any) if a powerful gamma-ray burst were to hit it directly, ... A: Interesting question! And this is one that we don't have a lot of observational evidence to ... | |
| Black holes, electric charge | 6/11/2009 |
| Q: Since not even light can escape the event horizon of a black hole, if a black hole managed to ... A: I'm not quite sure I understand your question. I'll assume "beyond" the event horizon means ... | |
| Sun and 7.25 degrees..... | 1/21/2009 |
| Q: I have been reading through the questions and this seems to pop up quiet a bit. The question I have ... A: You are correct that there's no absolute frame of reference. However, in our solar system, the ... | |
| solar system | 1/20/2009 |
| Q: I am an young earth creationist so you know I think the big bang is a fairytale.My two questions are ... A: First, you may be surprised when I tell you that I'm a creationist also. I don't know of too many ... | |
| stars | 1/18/2009 |
| Q: why do all stars seem like there the same distance from earth. And does this have anything to do ... A: No problem. I'll always try the best I can to make sense of it. But believe me, there are some ... | |
| stars | 1/18/2009 |
| Q: why do all stars seem like there the same distance from earth. And does this have anything to do ... A: All the stars seem like they're at the same distance from earth because they're all so far away. ... | |
| Bright Star? | 1/13/2009 |
| Q: Hey James, Every clear night for the last week or so (could be longer can't say I've purposely ... A: The object that's caught your eye is actually not a star at all, but the brightest planet there is - ... | |
| black holes | 1/9/2009 |
| Q: i am 17 years old and i was wondering is it possible that when a star dies and produces a black ... A: We have a pretty good idea of how elements burn in a star's interior, starting mainly with a sphere ... | |
| partical collisions? | 1/8/2009 |
| Q: Professor Gort, in your reply to my last question (small cold sun) you said: charged particles from ... A: Yes, we have a pretty good idea of how fast these particles are travelling. In some types of stars, ... | |
| Small cold sun? | 1/7/2009 |
| Q: Professor Gort i'm not going to be very popular i think. I want to question the present sun theory. ... A: Believe me - there are no silly questions - only silly answers! And I hope this answer isn't one of ... | |
| expansion of the universe | 1/7/2009 |
| Q: I am wondering, since the expansion of the universe is accelerating, has there been any detailed ... A: For your first question, yes, the rate of expansion can be calculated. And I guarantee you - the ... | |
| expansion of the universe | 1/7/2009 |
| Q: I am wondering, since the expansion of the universe is accelerating, has there been any detailed ... A: You ask some very thoughtful questions! I hope to give you a little more "food for thought". First ... | |
| Supernova | 1/2/2009 |
| Q: How the mass and distance of a supernova affects objects in the universe? How forces influence the ... A: To answer your second question first, a supernova is just an "exploding star", so the forces that ... | |
| telescopes | 5/6/2008 |
| Q: why do telescopes in space get a more complete picture of space objects? A: Telescopes in space are outside of earth's atmosphere. Telescopes on earth must see through a very ... | |
| earths orbit | 5/5/2008 |
| Q: how does the earths rotation stay relatively predictable/constant??? A: Isaac Newton discovered the law of inertia - that an object at rest stays at rest, and an object in ... | |
| SIZE OF OBSERVABLE UNIVERSE | 4/30/2008 |
| Q: Gort, One of my biggest question is about the size of the observable universe. In one of your ... A: Although I'll never say "never", from what we know of physics today (mainly from Einstein), much of ... | |
| SIZE OF OBSERVABLE UNIVERSE | 4/26/2008 |
| Q: Gort, One of my biggest question is about the size of the observable universe. In one of your ... A: As the red-shift gets greater, it appears that Hubble's velocity / distance "law" is not linear. ... | |
| lightyear | 9/5/2007 |
| Q: How long does it take for the images of the stars in the sky to get here? ANSWER: Hi Rob, The time ... A: The sun has a proper motion and moves in the arm of our Galaxy (towards the star Vega in Lyra), and ... | |
| lightyear | 9/4/2007 |
| Q: How long does it take for the images of the stars in the sky to get here? A: The time it takes for light from stars to reach us depends on how far they are away. The nearest ... | |
| Black Hole Collapse Velocity | 9/2/2007 |
| Q: When a large star collapses to a black hole why doesn't the collapse velocity approach the speed of ... A: I forgot to mention on the "rotation" question, all angular momentum is measured at the event ... | |
| Black Hole Angular Velocity | 9/2/2007 |
| Q: When a massive rotating star collapses to a black hole why isn't the rotational angular velocity of ... A: When a rotating star collapses, you are correct that conservation of angular momentum (which is ... | |
| How did the observable universe get so big in so | 5/28/2007 |
| Q: In a recent lecture it was stated that the observable universe is fourteen billion years old, but ... A: You're welcome. If you still have a few dolars left, I also recommend "Seeing Red" by Halton Arp, ... | |
| How did the observable universe get so big in so "short" a timem | 5/28/2007 |
| Q: In a recent lecture it was stated that the observable universe is fourteen billion years old, but ... A: I wish I had attended that lecture! First, let me say that this is a highly speculative area, and ... | |
| string theory | 5/26/2007 |
| Q: I want to ask that according to string theory there was not any singularity at beginning of ... A: I'm not sure I can help much in this speculative area, but I'll try. First, I hope you've had a ... | |
| moon color | 5/20/2007 |
| Q: What color is the moon? Do you know of a book or website to support your answer? A: This was a fairly difficult question! Surprisingly, there's not many references that describe the ... | |
| facing side of the moon | 5/12/2007 |
| Q: The same side of the moon always faces us, therefore as the moon orbits around the Earth, it must ... A: The moon is "locked" into synchronous rotation with the earth, meaning that it always presents the ... | |
| supernovae | 5/7/2007 |
| Q: what is meant by super navae? A: A supernova is a star which explodes violently. There are two main types. In one type, a very ... | |
| Sloan Great Wall | 4/30/2007 |
| Q: It seems too unlikely that the formation of the Sloan Great Wall is due to coincidence. Is there ... A: The Sloan Great Wall is not a structure, as such, since the galaxies are not gravitationally bound. ... | |
| No Direction to Find Big Bang | 4/30/2007 |
| Q: I read your explanation that there is no direction to specifically look to find the big bang. I ... A: You've hit the nail on the head. Yes, we should see evidence of young galaxies when we see the ... | |
| Big Bang and Blackholes | 4/28/2007 |
| Q: Gort I was reading your answer about the blackhole universe theory, and I was wondering if it would ... A: For not knowing much about astrophysics, you just came up with one of the current theories on the ... | |
| DARK MATTER | 4/24/2007 |
| Q: in special relativity speed od of light is constantn & works as a linkage of connecting space & time ... A: The concept of datk matter was actually developed to explain the rotational dynamics of the Milky ... | |
| Big Bang | 4/21/2007 |
| Q: In the book "Death by Black Hole, Dr. Tyson states that at the Big Bank plus 1 second, the universe ... A: In cosmology, I really want to get across there's no consensus by scientists. There are popular ... | |
| SINGULARITY | 4/20/2007 |
| Q: Sir I want to ask that according to many models of universe there was a singularity at the ... A: This question is currently being studied by some of the best minds in physics. You're right - ... | |
| speed of light | 4/20/2007 |
| Q: in special relativity speed od of light is constantn & works as a linkage of connecting space & time ... A: The energy of the early universe has not been estimated with any certainty. The assumption of ... | |
| speed of light | 4/18/2007 |
| Q: in special relativity speed od of light is constantn & works as a linkage of connecting space & time ... A: You're probably referring to Einstein's statement that "according to the general theory of ... | |
| Big Bang | 4/15/2007 |
| Q: In the book "Death by Black Hole, Dr. Tyson states that at the Big Bank plus 1 second, the universe ... A: To answer the main point of your question, yes, gravity overwhelms the apparent recession of ... | |
| Big Bang | 4/14/2007 |
| Q: In the book "Death by Black Hole, Dr. Tyson states that at the Big Bank plus 1 second, the universe ... A: Very observant! I'll have to qualify my remarks with the fact that I haven't read Tyson's book. ... | |
| heliosheath | 4/12/2007 |
| Q: i just heard about the heliosheath. i have two questions if you will, (not very easy ones, i fear) ... A: That's the sort of feedback I'll accept! Actually, I was accepting feedback for years, but decided ... | |
| heliosheath | 4/11/2007 |
| Q: i just heard about the heliosheath. i have two questions if you will, (not very easy ones, i fear) ... A: We've "known" about the heliosheath (theoretically) at least from the late 1950's. In 1957, S. ... | |
| Supernovae | 4/1/2007 |
| Q: I've been reading up on the Permian-Period extinction theory and was wondering how close a supernova ... A: There's been considerable research into this lately. We'll look at it from two ways: The first is ... | |
| BOL | 3/3/2007 |
| Q: Recently you considered a question i had ... A: You are correct - particles accelerated along field lines near a sunspot is essentially the same ... | |
| What caused/came before the big bang? | 3/3/2007 |
| Q: Is it posible that as the universe ages black holes become more numerous and or grow larger & ... A: You've asked a very profound question. But the short answer to your question is "yes", what you ... | |
| Variability of information | 2/28/2007 |
| Q: Gort, Over the decades as we read and learn about astronomy and physics one thing stands out and ... A: I agree with what the article points out. Especially in astrophysics. I sometimes tell my class ... | |
| cosmology | 2/27/2007 |
| Q: I read today that the Hubble constant is supposed to give us the speed that galaxies recede from ... A: Yes, the Hubble constant seems to work for "nearby" galaxies, but once you start getting speeds ... | |
| What Did I See? | 2/26/2007 |
| Q: Yes, there may be (and probably is) a mundane explanation for what I saw. I live fairly close to ... A: Yes, I can confirm there's no astronomical phenomena which meets that description. Except one last ... | |
| cosmology | 2/26/2007 |
| Q: If the Universe is fifteen billion years old and the furthest stars are fifteen billion light years ... A: I think the confusion stems from the familiar terms of "age" and "expanding". With the universe, ... | |
| What Did I See? | 2/23/2007 |
| Q: I recently saw what appeared to be a normal star whose brightness intensified perhaps tenfold, then ... A: This is difficult to determine, but I don't think it was a star. If it was fairly low in the sky, ... | |
| SUN | 2/21/2007 |
| Q: Why do Sun get brighter in Noon then in early morining? A: The sun appears brighter around noon because the sun's rays are most direct then. At noon, they ... | |
| Big Bang | 2/16/2007 |
| Q: I know the scientific evidence for the Big Bang, but what I don't understand is why "we" see no edge ... A: The problem I think you're having is the name "Big Bang". A "bang" implies an explosion of ... | |
| Neutron Stars | 2/13/2007 |
| Q: Prof. Gort, I have a question about what it would be like to be on a neutron star. Years ago in an ... A: What you heard is partially true. But it's even more astonishing that that. The average density in ... | |
| Planet formation | 2/12/2007 |
| Q: James Gort, Thank you for the in depth answer. It helped to answer the question. However, I would ... A: I think the best explanation may come from Wikipedia, under "cold welding". That states: "It is ... | |
| "earth flares" | 2/11/2007 |
| Q: Do you think it's feasible that earth could produce "earth flares?" Like "solar flares" but these ... A: You've asked a very interesting question! I've not heard such a theory proposed before, but I've ... | |
| Planet formation | 2/11/2007 |
| Q: When a rocky planet is forming, how do the pieces of rock "stick" to each other? In the 70's I heard ... A: The condensation process (in which planets were formed from the solar nebula) began to be studied ... | |
| Observing Satellite by Naked eyes | 2/3/2007 |
| Q: Is it possible to see a satellite using our naked eyes. I recently saw an object in the sky in the ... A: Yes, you can see many satellites with your naked eyes. None of them (to my knowledge) have exterior ... | |
| JUSTIFY The Big Bang | 1/12/2007 |
| Q: Scientists say the universe is expanding. That's their evidence for the big bang. But scientists now ... A: If you want me to justify the Big Bang, then you've asked the wrong person. If, on the other hand, ... | |
| What Did I See???? | 1/8/2007 |
| Q: This occurred late in the evening, around 10pm. Although I would have loved this to have been an ... A: That makes sense, if it wasn't seen by you for a couple of hours. Perhaps the military is covering ... | |
| What Did I See???? | 1/8/2007 |
| Q: I witnessed something which has puzzled me for many years. Now that we have the internet, I ... A: This is a pretty difficult one, but I'll do my best. First of all, I can confirm what it was not. ... | |
| Multiverse? | 12/27/2006 |
| Q: Gort. I have a question related to the idea of a multiverse. I realize this is probably considered ... A: You've asked a very interesting and intriguing question. But one we may never know the "answer" to. ... | |
| super nova | 12/19/2006 |
| Q: what happens if the core is able to produse iron before imploding A: If a star is more massive than about 8 times the solar mass, it is able to produce iron through ... | |
| neutron stars/ pulsars | 12/16/2006 |
| Q: RE:"To answer your first question, all pulsars are neutron stars (currently accepted models!), but ... A: A pulsar is just the observational evidence for certain neutron stars - ones that are oriented ... | |
| neutron stars/ pulsars | 12/15/2006 |
| Q: So... there are neutron stars that do not rotate, but still expel EM radiation? By inference these ... A: Yes, a non-rotating neutron star (which could very likely still emit strong EM radiation from its ... | |
| aurora borealis (sp?)/ Northern Lights | 12/15/2006 |
| Q: I saw today on the news that the northern lights may be seen in Kansas tonight. I need to know what ... A: That's very difficult to predict. It depends on what materials were ejected by the sun, how fast ... | |
| neutron stars/ pulsars | 12/14/2006 |
| Q: 1. Are neutron stars and pulsars the same? 2. Are black holes a hole in space/time, or is there a ... A: To answer your first question, all pulsars are neutron stars (currently accepted models!), but not ... | |
| "we are stardust" and "we are nuclear waste | 12/14/2006 |
| Q: hey James,Can you help me out with the quotes "we are stardust" and "we are nuclear waste" in terms ... A: According to the currently accepted theory of stellar evolution, we are both "stardust" and "nuclear ... | |
| Astrology? | 12/8/2006 |
| Q: What is the next month during which a full moon will not be seen in Wilmington, DE? A: Because the lunar month (the time between successive new moons or full moons) is 29 days, 12 hours ... | |
| A question about black holes | 12/2/2006 |
| Q: I am a student from Israel. I'm doing a school project about "Black Holes", and i have a question I ... A: In the center of a black hole, there is mass. According to Einstein, all mass distorts ... | |
| hi | 11/24/2006 |
| Q: i was just wondering how many times have you seen black holes?and have you ever seen Ufo's? A: I've never seen a black hole. No one has. They're black and so they're invisible. But we can see ... | |
| Astronomy | 11/5/2006 |
| Q: Why can we never see a full moon in the sky at mid-day? A: The full moon means that the sun is on the opposite side of the earth, illumimating the moon. If ... | |
| Speed | 10/26/2006 |
| Q: I know the earth travels about 67.000 mph around the sun to make it all the way around each year. ... A: There is new data coming in on this all the time, mainly from the Hippararchus satellite. But a ... | |
| big bang and age of everything | 10/10/2006 |
| Q: O K, thanks...... Just how old is the cosmos/universe ? I have read where it's anywhere from 15 ... A: This one's easier to answer. One current model (the most widely accepted) puts the universe at ... | |
| big bang and age of everything | 10/9/2006 |
| Q: How can astronomers say they are looking at the universe only a few billion years old if we were ... A: You've asked a very profound question. And one I've not seen raised very often. I wish I had an ... | |
| Multiple universe | 10/6/2006 |
| Q: Are we the only universe in space, it seems this would be the same as assuming we are the only ... A: Well, there's nothing in any known physical law which would prohibit multiple universes. And ... | |
| Black Holes and the Big Bang | 9/30/2006 |
| Q: If I understand correctly, a black hole results when a star more that a few times the mass of our ... A: Your idea of black hole formation is essentially correct, except the star starts with a mass over ... | |
| the Sun | 9/18/2006 |
| Q: What is the real name of the sun? A: The Sun is the only English name for the star which warms our solar system. The term is derived ... | |
| Asteroid Belt | 8/28/2006 |
| Q: Wow! You knew Prof. J. Allen Hynek?! I am a big fan of Jacque Vallee. It's really neat you were ... A: To be honest, I haven't kept up on a lot of recent research in this area. But I'm very glad to see ... | |
| Asteroid Belt | 8/28/2006 |
| Q: Does this theory hold any scientific merit, if not why? ... A: You've asked the right person. Many scientists would discount this theory as "outside the ... | |
| Black hole | 8/27/2006 |
| Q: I have many questions about Astronomy but I will ask some few only: 1) What is the end of a black ... A: 1) If you're asking whether a black hole will have an end and eventually die, the answer is ... | |
| Photographing the earth from space | 12/31/2005 |
| Q: Howdy do. If one were in geostationary orbit, hanging out with all the cool satellites, and one were ... A: Since the geostationary satellite is 26,000 miles up, and the earth is about 8000 miles in diameter, ... | |
| Measuring Degree of Ellipticity | 12/30/2005 |
| Q: How can I quantify the degree of ellipticity of various oval shapes or orbits? Can I measure the ... A: Yes, that's the only scale I'm aware of to quantify the eccentricity of an ellipse. But you've hit ... | |
| Measuring Degree of Ellipticity | 12/29/2005 |
| Q: How can I quantify the degree of ellipticity of various oval shapes or orbits? Can I measure the ... A: Yes, you can measure the widest point (call this length 2a) and the narrowest point (call this ... | |
| Cosmology | 9/2/2005 |
| Q: if the Universe is actually open in geometry and there is an end to it (far beyond our horizon)then ... A: You're asking something beyond all scientific knowledge. But if you're asking for a guess, I can ... | |
| Space | 9/1/2005 |
| Q: 1) Do all galaxies rotate counterclockwise? 2) How fast is our Solar System rotating around the ... A: 1) No, galaxies rotate in random directions and orientations. By the way, the appearance of a ... | |
| moon | 8/27/2005 |
| Q: Can the moon at times be seen by both sides of the world at the same time? Since I have seen it ... A: The way you phrase the question, I'd have to say "sometimes". If we see the moon just rising in the ... | |
| space | 8/25/2005 |
| Q: None of the Galilean satellites have an atmosphere that is anything like as substantial as Titan, ... A: You've asked a very interesting question, and one subject to much current research. As you probably ... | |
| astrophotography | 8/19/2005 |
| Q: i want buy a digital camera for astrophotography but my budget is limited, is it suitable to buy ... A: I'm not up on all the latest equipment, but you want to ensure that there's a "bulb" mode and good ... | |
| Moon's Orbit | 8/17/2005 |
| Q: Man made "space junk" as it orbits earth eventually enters back into the earth's atmosphere and ... A: You've asked an extremely difficult question, requiring a good deal of orbital mathematics to prove. ... | |
| mass, speed and gravity | 8/5/2005 |
| Q: here is my last question. light travels at the speed of light so is that affected by time also what ... A: You can think of light as the "carrier of time". As you go faster, time slows for you (as measured ... | |
| mass, speed and gravity | 8/3/2005 |
| Q: If like you said that it would be impossible for an object to go at the speed of light if somehow ... A: As I said, an object going at (or above) the speed of light would be seen to become infinite in ... | |
| mass, speed and gravity | 8/2/2005 |
| Q: if a large object was traveling through space at the speed of light or more, will it hae gravity? ... A: That's an interesting thought question, but it might not be possible to test, because Einstein said ... | |
| Mars | 7/26/2005 |
| Q: I received this email yesterday. CLOSE ENCOUNTER WITH MARS Never again in your (or my) ... A: Yes, that was an old clipping from 2003. In August, 2003, Mars made its closest approach to Earth ... | |
| historical accounts | 7/23/2005 |
| Q: I'm a recent college grad. I was talking a lifer friend of mine (he's been in college for 6 years) ... A: A. For the first question, I am not familiar with the earth being "one day behind". From a ... | |
| Void | 7/21/2005 |
| Q: Do we have a hypothesis or deduction with regard to what could be a void (something that lacks ... A: First, I'll give you my view (based solely on an opinion and not much research), but then I'll give ... | |
| Astronomy, Moon Orbit | 7/20/2005 |
| Q: Since I was a child I've noticed that the moon rises & sets pretty much between the same positions ... A: Good observation! As you know, the ecliptic is the path the sun appears to follow. Since it's ... | |
| Astronomy | 7/17/2005 |
| Q: im trying to buy a telescope for about £100 +- $170 i found two but im not sure which one to buy. ... A: The most important part of any telescope is that it is actually used. So a telescope must be easy ... | |
| seeing back in time | 7/12/2005 |
| Q: When we look at distant galaxies (or other distant objects), we see them as they were a very long ... A: Mike, That message was a follow-up to the original message. Perhaps you didn't receive it. But ... | |
| Solar physics | 7/5/2005 |
| Q: about solar lightning Dear Professor Gort, Thank you for your very lucid explanation of lightning ... A: Actually, we get light only indirectly from the interior fusion reactions. All the radiated photons ... | |
| Solar physics | 7/5/2005 |
| Q: I was recently at a site called: The Surface of The Sun ... A: This is exactly the sort of question that "AllExperts" is all about. I'm very glad you asked me. ... | |
| Travelling to Mars at the speed of light | 6/20/2005 |
| Q: How long would it take, on average (considering that Earth and Mars might be in different stages of ... A: This is a very difficult question to answer "correctly", and much depends on what you mean by "on ... | |
| galectic formation | 6/18/2005 |
| Q: GALACTIC SEEDS The rapid formation of galaxies has been problematical to cosmologists. The ... A: First, let me preface my remarks by saying that my expertise is not in cosmology, but I am an ... | |
| The Hubble Telescope | 6/14/2005 |
| Q: Where is the Hubble Telescope, sir? A: The Hubble Telescope orbits the earth at an average altitude of about 352 miles. If you'd like to ... | |
| What colour are the planets? | 6/13/2005 |
| Q: 1. What colour are the eight planets: mercury, mars, jupiter, venus, neptune, saturn, pluto, and ... A: 1. I think the best site I can recommend is ... | |
| Mars | 6/11/2005 |
| Q: Gort, Is it correct, or is it a hoax, that ... A: Richard, I forgot to mention - this is considered the most favorable period for telescopic ... | |
| Shoemaker Levy | 6/9/2005 |
| Q: I have read much of the impact of Shoemaker Levyon Jupiter, what I want to know is... How big were ... A: About 20 large fragments (which were seen and identified from space and ground observatories) ... | |
| Magnitude | 5/31/2005 |
| Q: How can we measure magnitude of stars by a CCD camera? And how can we precisely do it? Sincerely. A: Glad to see you're interested in pursuing some real science! The short answer is easy, but the ... | |
| Balance point betwen earth and moon | 5/26/2005 |
| Q: I recall several years ago reading about three points in space between the earth and the moon where ... A: I think you're referring to LaGrangian Points. There are five such points in the earth-moon system. ... | |
| The line | 5/20/2005 |
| Q: I've got a picture of how he explained it. The information you gave me did ring a bell - moreso the ... A: Tom, The time for a complete revolution around the center of the galaxy is 220 million years, so ... | |
| The line | 5/19/2005 |
| Q: my teacher was talking about our galaxy and how the earth moves very slowly over a line or some ... A: I'm not quite sure what you teacher was referring to, but I'll try and help. The sun is located ... | |
| Recently Polarized Sunlight | 5/13/2005 |
| Q: I and some acquaintences have recently noticed that around sunrise and sunset sunlight seems to be ... A: Good observation! I'm not sure what's causing it - it could be a volcano, additional air pollution ... | |
| Earth and Planets | 4/22/2005 |
| Q: If the Earh stopped revoling around the Sun would the other planets in our solor system be sffected? A: If the Earth stopped revolving around the Sun (and crashed into the Sun because it wouldn't be in ... | |
| space adventure | 4/22/2005 |
| Q: Have you ever been into space? If yes please discrab you exerinces and fealing about what you saw in ... A: The Canadian Astronaut's Program was set up by Canada to train Canadians for space travel. Canada ... | |
| earth and sun | 4/22/2005 |
| Q: have you ever been in space? because i have a question for you. What would happen if the earth ... A: I have never been in space. If the Earth stopped revolving around the Sun, the Earth would not go ... | |
| Earth and Sun | 4/22/2005 |
| Q: If the Earth stopped revolving around the Sun would the Earth slowly go closer to the Sun? Also ... A: If the Earth stopped revolving around the Sun, the Earth would not go SLOWLY closer to the Sun, but ... | |
| space adventure | 4/20/2005 |
| Q: Have you ever been into space? If yes please discrab you exerinces and fealing about what you saw in ... A: No, I've never been in space. But I did apply to the Canadian Astronauts Program. Thousand of ... | |
| moon | 4/20/2005 |
| Q: If you cut the moon in half what would it look like? A: The moon does not have a liquid core like the earth does. It has a thin layer of dust on the ... | |
| Moon | 4/20/2005 |
| Q: What would happen if the moon stopped revolving around the earth? How would our tides be affected? ... A: If the moon was not there at all, the tides would be one-third as high (since the moon causes ... | |
| Earth's rotation | 4/19/2005 |
| Q: What would happen if the earth stopped rotating gradually? A: Sarah, The days would get longer than 24 hours, until one side of the earth would always be day, ... | |
| Astronomy | 4/14/2005 |
| Q: Can you explain me why: 1-"In 2005, the "Winter Solstice", or the northern hemisphere tilted the ... A: Look up "Winter Solstice" on Google. The short answer is because the earth's axis is tilted about ... | |
| Astronomy | 4/14/2005 |
| Q: "What night is the longest night of the year?" Thank you very much! A.Vafa A: In 2005, the "Winter Solstice", or the northern hemisphere tilted the greatest amount away from the ... | |
| strange question | 4/8/2005 |
| Q: My question is going to sound a little crazy but please If u can answer it, Then please do. ... A: Hassan, There are no crazy questions - only crazy answers! And I hope this isn't one of them. The ... | |
| galaxy question | 4/2/2005 |
| Q: Is there a mathematical equation that represents a spiral galaxy such as the milky way? If so, ... A: The best source I know of which can help answer your question is a book entitled "Spiral Structure ... | |
| Astronomy/solar system | 12/31/2004 |
| Q: Is "What is the difference between Earth's moon and Pluto's moon" a project i can do for a ... A: A science fair teaches "Independent research" (like a real scientist does). So look up "Charon" and ... | |
| Aviation and Space Science | 12/30/2004 |
| Q: My organisation [NYDT] set up the Africa Space School for schools in [Southern] Africa. We have an ... A: I would be most happy to participate. Currently, I am a Professor of Astrophysics at the University ... | |
Astronomy
Answers by Expert:
James Gort
Top Expert on this page
Expertise
Questions on observational astronomy, optics, and astrophysics. Specializing in the evolution of stars, variable stars, supernovae, neuton stars/pulsars, black holes, quasars, and cosmology.
Experience
I was a professional astronomer (University of Texas, McDonald Observatory), lecturer at the Adler Planetarium, professor of astrophysics, and amateur astronomer for 42 years. I have made numerous telescopes, and I am currently building one of the largest private observatories in Canada.
Publications
StarDate, University of Texas, numerous Journal Publications
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