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For further exploration



Asphang, E. “The Small Planets.” Scientific American (May 2000): 46. On asteroids, including results from the NEAR mission.

Beatty, J. “The Falcon’s Wild Flight.” Sky&Telescope (September 2006): 34. On the Japanese mission to asteroid Itakawa.

Beatty, J. “NEAR Falls for Eros.” Sky&Telescope (May 2001): 35. On the first landing on an asteroid.

Betz, E. “Dawn Mission Reveals Dwarf Planet Ceres.” Astronomy (January 2016): 44. First images and discoveries.

Binzel, R. “A New Century for Asteroids.” Sky&Telescope (July 2001): 44. Nice overview.

Boslaugh, M. “In Search of Death-Plunge Asteroids.” Astronomy (July 2015): 28. On existing and proposed programs to search for Earth-crossing asteroids.

Cooke, B. “Fatal Attraction.” Astronomy (May 2006): 46. On near-Earth asteroid Apophis, its orbit, and what we can learn from it.

Durda, D. “Odd Couples.” Astronomy (December 2005): 54. On binary asteroids.

Durda, D. “All in the Family.” Astronomy (February 1993): 36. Discusses asteroid families.

Oberg, J. “2013’s Historic Russian Meteorite Fall” Astronomy (June 2012): 18. On the Chelyabinsk event.

Sheppard, S. “Dancing with the Planets.” Sky&Telescope (June 2016): 16. On Trojan asteroids that “follow” planets like Jupiter.

Talcott, R. “Galileo Views Gaspra.” Astronomy (February 1992): 52.

Yeomans, D. “Japan Visits an Asteroid.” Astronomy (March 2006): 32. On the Hayabusa probe exploration of asteroid Itakawa.

Zimmerman, R. “Ice Cream Sundaes and Mashed Potatoes.” Astronomy (February 1999): 54. On the NEAR mission.


Aguirre, E. “The Great Comet of 1997.” Sky&Telescope (July 1997): 50. On Comet Hale-Bopp.

Bakich, M. “How to Observe Comets.” Astronomy (December 2009): 50. A guide for amateur astronomers.

Gore, R. “Halley’s Comet ’86: Much More Than Met the Eye.” National Geographic (December 1986): 758. (Also, the March 1987 issue of Sky&Telescope was devoted to what we learned from Halley’s Comet in 1986.)

Hale, A. “Hale-Bopp Plus Ten.” Astronomy (July 2005): 76. The co-discoverer of a naked-eye comet tells the story of the discovery and what followed.

Jewett, D. “Mysterious Travelers: Comet Science.” Sky&Telescope (December. 2013): 18. Nice summary of what we know about comets and questions we have.

Rao, J. “How Often do Bright Comets Appear?” Sky&Telescope (November 2013): 30. Nice summary of bright comets in the last century and what factors make a comet spectacular in our skies.

Sekanina, Z. “Sungrazing Comets.” Astronomy (March 2006): 36.

Sheppard, S. “Beyond the Kuiper Belt.” Sky&Telescope (March 2015): 26. On Sedna and the Oort cloud.

Stern, S. “Evolution at the Edge.” Astronomy (September 2005): 46. How comet nuclei evolve with time.

Talcott, R. “Rendezvous with an Evolving Comet [Rosetta at Comet 67P/C-G].” Astronomy (September 2015): 44.

Tytell, D. “Deep Impact’s Hammer Throw.” Sky&Telescope (October 2006): 34. On the mission that threw a probe at the nucleus of a comet. See also (June 2005): 40.

Weissman, P. “A Comet Tale.” Sky&Telescope (February 2006): 36. A nice review of what we know and don’t know about the physical nature of comets.

Questions & Answers

How are Roche Worlds formed?
AlteredEdge Reply
In need to read some books about Astronomy so how can in get it actually leg live in Ethiopia can uh help me with that?
Mom Reply
I am sri Sharan .m .what is my best favourable numbers
Madhesh Reply
how can we know it
bahut hard
Why no object can travel with speed greater than light?
geometry Reply
Because the mass of light particles is zero
Can mass be negative?
anybody stated that the light is the only thing is speed
geometry are you a korean or kpop fan
in this universe anything can be faster than light because we simply can't get to an conclusion
I am a an Army but lets not bring spam here.
But why mass can't be negative. What I mean is how can we claim an object made of strange matter has positive mass. In other words, theoretically can negative mass exist?
in our observable universe nothing is faster than the speed of light
But theoretically, is it possible? Sorry I'm being very curious..
I don't know about dark matter but may be you should think about dark matter because dark matter are really strange
Exactly so theoretically, an dark matter lazer can be greater in speed. Also maybe quartz..
may be but i am not sure about quartz and btw techyons travel faster than light but techyons are hypothesized
there are many objects which are perceived to be faster than light
The object have their own declination rate in speed,the air friction can develop higher temperature resulting the object to be disappear in molecules,not considering the Physical conditions in space.The object should be unaffected with the air friction and also speed should proportionate with fuel.
what is Deja Vu theory?
rockstar Reply
Have you ever felt like something has ever happened before? That's Deja Vu. The Deja Vu theory says that once you have those visions, you are actually experiencing what an alternate reality would have been. Basically it's the collision of both our universe and another.
Yeah it gives us an idea about the existence of a parallel universe
is this a hypothesis? or theory? isn't there something with your brain/memory processing the image or info twice in a few seconds?
I do also love this experience, seems so unreal but real all at once.
this can be real if we will solve the mystery of quantum physics .
I was giving just giving my own hypothesis of the general topic. While it would be interesting to find that we transitioned through dimensions, I think it just boils down to a heightened ability to predict future outcomes and a series of subconscious decisions to enact one of those possible outcomes
What I'm saying is that it's all in your head. 😂
yeah its all in our heads for sure, the brain is amazing, all of the above hypothesis really interesting. one day hopefully we might figure it out.
I hope that this hypothesis might be proved true
I feel deja vu is kind of a wormhole which connects us to a parallel universe.
I like what you said 'alterededge' "dena vu" is a vision of a past memory reenacting itself at an unexpected time and place. traveling and transitioning through dimensions.
opps, "deja vu"***
you are are right Geometry Lover.
Deja vu might even prove the existence of future time travel.
Well I'm not exactly saying it's a memory, it still hasn't happened yet, more like subconscious pre-cognitive thinking, where your mind eventually leads you down a path that makes the "deja vu" experience reality true after you had it.
We says time as a 3rd dimension and space as a fourth dim, so as come to 5 dimension what we say? I hope you got my point
According to string theory there are 10 dimensions
Yes you are right Mishra
But Tesseract is said to be 5 dim
How do giants planets remain gaseous when they are located in cold regions of the solar system? Do they generate enough heat and if they do, are they not able to also heat their moons?
Kuda just to answer part of your question. The gas inside Saturn for example is extremely dense not like gas in a room. The definition of gas is that the particles have little to no interaction between each other meaning there's no chemical bonds.
hello ,what kind of question is that?
Bata Reply
what is weather
Susil Reply
Hey guys, question. It is said that Uranus' famous axial tilt of 98 degrees was caused by collisions billions of years ago. How can a celestial body/object 'collide' with a body (Uranus) which is made up of gas and has no surface?
Joey Reply
Although Uranus has no phyiscal surface, it still has a core. It's possible that in the early stages of the solar system, a rouge planet or moon tore through the upper levels of the atmosphere and was able to penetrate the lower cloud levels and eventually reach gas giant's core.
are there aliens in the universe?
Lesego Reply
might be possible but there is no true evidence of it.we can only assume because we don't know the exact size of universe,it's infinite,so possibilities always shown is in infinite.
might be possible because UFO's are being seen on earth
is also a little ridiculous
I feel I need to confess the only life the universe created for us to see and feel is the one in human form on Earth. its possible we make ourselves sick straining our thoughts to think of connecting with human life on or in any other realm other than the one we are in.
goodnight, I will continue our conversation tomorrow.
there was nothing created for anyone, its literally just there, there is no reason, it just is, don't be dumb
We Are Not Special, We Just Happen To Be The Species That Evolution Has Shaped So Far.....
If the universe is limitless, life could be limitless as well. According to science and mathematics of course!
The universe is so vast and complicated it's impossible to ever rule out the possibility of intelligent life, but the gradual realization by human society is that we are not "special" in any given way. I recommend everyone here watch Issac Arthur on Youtube, he takes a look into the Fermi Paradox.
Thank You AlteredEdge, I Will Check It Out.....
Adam i have a question
Why does traveling at close to light speed or being near super dense objects cause time to dilate?
Andrew Reply
good question. time is only what we made it. the way light travels with and without gravity has always been a wonder to me.
What do you mean without gravity?
I'm actually not sure, this might be a silly question but does gravity effect light in respect to time?
As you move faster the slower the time
yes , gravity can effect light you can take example of black holes .
yes this makes sense, so do we know what kindo of effect it has on time around a black hole?
Since a black hole has an extreme amount of mass compacted into such a tight density, it warps space and time around it. Why? The main reason is gravity. It is always the dominant factor in black holes. Light in this case is absorbed like everything else.
Time in a black hole is slowed down compared to outside the black hole, this again is caused by gravity. Same principle works on Earth.
but black holes only bends space-time febric and light didn't change its path it always travel in straight line but the space febric is curved so it looks like that light bend or obserbed by black holes.
Black Holes do bend the fabric of space-time, but light is no exception. Light is matter just like everything else.
this is great info/convo. without a black hole, does gravity effect light in any other way,? like the way water bends light. just curious if the knowledge is there, any site recommendations for research, would be greatly appreciated.
So like your saying, outside of the extreme of a black hole, light travels in a straight line. However when it comes in contact with a large mass (lets say the sun) it curves space around it. So from an outward appearance the light bends to the gravity which causes what we call gravitational lensing
yes exactly, ok wow yes that makes alot of sense, thank you very much for this info/feedback, gravity seems like the top of the food chain in the universe, trying to find out, for my own research, how much we know about it to date and its affect on other objects/masses etc. thanks again
Of course! Also to help you out incase you didn't already know, but gravity travels in waves and varies in strength.
wow ok I did not know that either, thank you,. slightly like the way sound travels maybe? other info I will be glad to hear if your sharing, thanks again AlteredEdge
what is the definitions of planet
Mitrajit Reply
A celestial body orbiting around a star
How to appear for MCQ in this app
nitisha Reply
I l don't understand questions
Nkateko Reply
which quesrions?
let it be
How to make a telescope
Amit Reply
optical mechanics
Why the God make universal ?
because God itself don't know.
Which one has the ring
Isaac Reply
Saturn venue and even Jupiter all have rings the rings on Jupiter, however, aren't so easily noticed due to them only being viable through infrared
visible *
they each have three rings but not as you might think just think of them all as one big ring because that's basically what they are but they are desperate individual rings

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