Ask the Staff Astronomer!


  Astronomical Diagrams  Horsehead Nebula  Globe 



We know that the Universe is an unfathomably large place and astronomy is infuriatingly complicated.   Nevertheless, we want to help YOU understand the machinations and mysteries of this annoyingly complex cosmos.   Toward that end, we ask you to send your astronomy/astrophysics questions to our staff astronomer:

He'll not only send a response to you personaly, but we'll post the question and answer to this web-pageI.

I. "Is gravity thought of as "just" a measurement of the space-time deformations? If it is, why would astronomers be looking to detect 'gravity waves' or 'gravitons'?"

II. "Ok, so, I know that nothing can go faster than the speed of light. The other day, though, I heard that particles which travel faster than light emit a strange kind of blue radiation. But, I didn't think anything could go faster than light?"

III. "If the universe has bazillions of stars, and we can "see" 13 or so billion years into the past, why isn't the night sky white with the light of all those stars?"

 IV. "I was told that light has no mass. I also know that gravity is a force between two or more massive objects. So, how is it that massive objects can affect the trajectories of light particles, or photons?"

 V. "How does time stop?"

 VI. "If the Universe started in a Big Bang, how far are we from the center and what happened before it?"

VII. "I saw recently that the Voyager Probe encountered the Heliosphere. How long can it keep traveling before it runs out of fuel?"

VIII. "How do you know that the Big Bang occurred?" 

IX. "If black holes are black, how can we possibly discover them?"

X. "I heard that some astronomers think that there still might be active life forms elsewhere in the solar system. Where would it be?"

XI. "Hello! I saw something the other day that doesn't seem to make any sense. I read that Mars has the longest orbital period of the planets. Can that be right? I thought the most distant planets had the longest periods."

XII. "I read an article that said that winter is the shortest season.  Is that right? It feels like it is never going to end!"

XIII. "How did astronomers determine that the Cepheid brightness depends on their periods? Wouldn't they have had to have known the distances first?"

XIV.  "Can you explain the transit method that astronomers use to find exo-planets?"

XV. "I know that many tests have been conducted to corroborate General Relativity. I understand why the Eddington expedition's* star field images were helpful. But, why was the 43 arc-second Mercury perihelion shift important in verifying General Relativity and what does it mean?"

XVI. "Hello! I'm sorry, this might be a stupid question,* but at night I see the stars overhead. Are there as many stars under our feet as above us?

XVII.  "The Apollo astronauts collected rocks from the Moon and brought them back to Earth. Fine. But, I heard that pieces of the Moon, called lunar meteorites, were already here and are still here scattered around the planet. Is that true? How did they get here?"

XVIII. "Why do so many physicists and cosmologists assume that gravity and other fundamental forces are the same throughout the entire universe? Couldn't space-time have different qualities in different 'locales' within it?" 

XIX. "I remember somebody once said that Jupiter was the second brightest planet after Venus. However, I saw in an almanac that Mercury will be brighter than Jupiter this July. How is that possible?"

XX. "Is it true that you can balance eggs on their ends on either equinox?" 

XXI. "Is the Moon really larger when it is on the horizon? I heard that the Moon's distance isn't always the same? Is it closer when it is lower in the sky?"

XXII. "Sometimes when I go outside to look at constellations, I wonder, will they be the same when I am 100 as they are now? I heard they do change, but doesn't it take a long time?"

XXIII. "So is the moon being attracted by another planet and eventually it will move into another planets orbit? Is Earth also moving closer towards the sun? Will all the planets eventually be pulled into the sun and have a flaming end?"

XXIV. "I was listening to one of those radio quiz shows and they had a question on it I didn't understand. 'How fast would a 10 meter rod have to travel in order to fit into a 5 meter space,' or something like that. The answer was, like, 86 percent the speed of light.  Could you explain this?

XXV. "Venus and Jupiter are going to be very close together on July 1st, you wrote in a recent article. Will these two planets being so close together affect Earth gravitationally? Will we have higher tides or anything like that?"

XXVI. "Could you explain 'Nemesis?' Is the Sun actually part of a binary star system?"

XXVII. "The North Pole has sunlight 24 hours a day now and will until early autumn. But, it is only 5 -6 degrees Celsius presently. If it has sunlight all the time, why isn't the Pole warmer?"

XXVIII.  "My Snapple Cap had a fact on it I wanted to ask about. It said that cows resting or grazing align themselves with Earth's Magnetic poles. My question is 1. how do they know that cows do that and 2. how do cows know where the magnetic field lines are?"

XXIX. "Could you please explain 'parallax' again? How does it work when you're measuring the distances to the stars?" 

XXX. "Do you think there are any parts of the Universe that will always remain unknown to astronomers?" 

XXXI. "How much does aphelion affect our weather? We're at aphelion in the summer. Would our summers be warmer if we were at perihelion, instead?"

XXXII. "How far away could we travel from the Sun and still be able to see it?"

XXXIII. "How can we know what we know about exo-planets?"

XXXIV. "Is Polaris the north star for all the other planets just like it is for Earth?" 

XXXV. "Stephen Hawking and other astrophysicists have proposed that our cosmos is just part of a 'Multiverse." How can this be scientifically proven? Even if it were correct, what would happen if our universe collided with another universe?"

XXXVI. "Are all planets in orbits such that they are in the same plane as Earth's orbit or are we missing many planets because they never transit their star in relationship to Earth? Or does this prove that the universe was created just for us?" 

XXXVII. "Does the Moon have gravity?" 

XXXVIII.  "Is it true that Vega will be our next North Star?" 

XXXIX.  "Astronomers say that long period comets come from the Oort Cloud, which they have never seen. If astronomers have never seen the Oort Cloud, how do they know it exists?"

XL.  "Do the constellations look the same from other planets?" 

XLI. "Do gravity waves travel at light speed?" 

XLII. "You mentioned that Mercury will transit the Sun in May 2016. Does Earth transit the Sun from the viewpoint of other planets?" 

XLIII. "What is the closest star that isn't visible to the unaided eye? I have a bet that it is more than 100 light years away." 

XLIV. "Astronomers can determine the distances to the closest stars by measuring their parallax angles. Before they knew any stellar distances, how did they know which stars were in the foreground?" 

XLV. "Why are some constellations chosen as part of the zodiac and some not? Why can I be a Virgo, but not a Lupus? A Gemini but not a Lyra?"

XLVI. "What does it mean when astronomers say we're all made of star dust?"

XLVII. "Is Pluto a planet again?"

XLVIII. "If there are 13 constellations in the zodiac, how come we only acknowledge 12 of them and ignore old Ophiuchus the Serpent Charmer?"

XLIX.  "Is the Sun getting hotter? If so, why? Will Earth eventually become too hot for life?" 

L. "How far did Alan Shepherd's golf ball go when he hit it on the moon? Could somebody theoretically hit a ball hard enough to make it leave the moon altogether?" 

LI. "I wondered, if the Moon is moving away from us, will there come a time when there are no more total solar eclipses?" 

LII. "Why is the vernal equinox called the "First Point of Aries" when the Sun is actually in Pisces on this date?" 

 Astronomer painting

Questions answered by
Edward Gleason, Level XXIII Astronomer