Starship Asterisk*

If we are going to recommend anything in the field of making information accessible by visual means, the work of Prof. Edward Tuft is pre-eminent.

See: http://www.edwardtufte.com/tufte/

John

Dave, You have your opinion, but you're splitting hairs when you say 'it's not an an image'. This certainly was not a photograph, but the header says either or. An 'image' can be a representation of something by other means, and what is a movie but a series of still photographs? Movement can add muc...

All, As the APOD says, on its header, "Each day a different image or photograph of our fascinating universe is featured" This was an image that was very different, fascinating and about understanding our Universe, so I say full marks to APOD for putting it up! Not that I understood it! John

Wolf,
In that case you will have considered my point that the cratering is older than the maria.
Your conclusion?

John

This might be of interest: http://history.nasa.gov/SP-345/ch24.htm Most of the impacts that mark the Moon came from the residue of the original Earth system, ie, very, very early. The question of whether the Earth shields the Moon from significant impacts depends on the age of the maria, and the his...

Because the Moon was not always tidally locked to the Earth. When it was formed, it would have had its own rotation. See: http://en.wikipedia.org/wiki/Tidal_locking The original cratering was probably even all over the Moon. The later maria formed where the crust was thinner, smoothed out the crater...

Hey, CC, keep up.

Although no one took up the challenge here, there was a PREVIOUS illuminating but not explanatory exchange of views on BAUT: http://www.bautforum.com/showthread.php?t=52156

John

Seeing things in 'reverse' on such pictures is common. Much of our 'seeing' is processing in the eye and brain, that relies on familiar cues and light direction. When those are absent, we cannot 'see' things as they are. A famous illusion relies on this - as in the staircase on this page: http://wil...

kovil, The article is almost as obscure as dark matter itself! But it does say,"The dark matter map was constructed by measuring the shapes of half a million faraway galaxies. To reach Hubble, their light has had to travel through intervening dark matter, and the path of the light is slightly ...

kovil, The aratcile is almost as obscure as dark matter itself! But it does say,"The dark matter map was constructed by measuring the shapes of half a million faraway galaxies. To reach Hubble, their light has had to travel through intervening dark matter, and the path of the light is slightly ...

Can't answer the above, but I followed the same link and found the Wkipedia saying, "For more massive stars, electron degeneracy pressure will not keep the core from collapsing to very great density, leading to formation of a neutron star, black hole, or, speculatively, a quark star." A &q...

Rather more useful links are found aplenty by Googling for 'circumhorizontal', or just going to the Wikipedia entry:
http://en.wikipedia.org/wiki/Circumhorizontal_arc

How are you going to link this in with interplanetary war, CC?

John

Well done, flieg! And that ?sink hole is almost right in line with the streak, so is likely to be associated. "Flieg's sink hole"? I admire your ability to cross your eyes. Even with my nose on the screen, I couldn't fuse the images, so here's another way, not as good, but may be applicabl...

http://www.nasa.gov/mission_pages/mars/ ... 09023.html

Love to read discussion of the assymtry of this impact. Rays to one side, secondary cratering to thhe other.

John

Later: BINGO! Cassini-Huygens website: http://www.esa.int/SPECIALS/Cassini-Huygens/SEMAJIZTIVE_0.html "The mountains probably formed when material welled up from below to fill the gaps opened when tectonic plates pull apart, similar to the way mid-ocean ridges are formed on Earth. " Maybe ...

The black shadow - clouds of ice particles? They reflect radar. And a straight line - are we into crater chains again? A linear strike, that opens a crack down to liquid, that then wells up, into a linear mountain chain? Like the Mid-ocean rift on Earth, but with less gravity and no tectonics? John

My apologies. I wrote above that: If the ball enters a smaller gravity field with a steeper gradient, like that of a planet, then objects on the far side of the CCoM from the planet are going too slow for their new orbit; they experience a force pulling them away from the planet into a higher slower...

Thanks, Bruce. Strangely, while it doesn't work as a link, it does work with the backslash "\" when entered into my browser (IE). And that is the way the address appeared when I searched for Pacholka's name, went to the Orange County site and found that pic in the album. I just copied the ...

If you are a good enough photographer, you can use flash and see stars in the result! See the work of Wally Pacholka. Some of his work looks as if it is staged, such as this one, where the mesas appear to cast a flash shadow on the starry background! Obviously a stage set! http://www.ocastronomers.o...

Bob, I feel your pain! But maybe we're just too geocentric, deposition would be quite unlike Earthly windblown detritus. And look at two places in that pic: 1/ the lumpy rock, aboput four o'clock from the astronaut. There's dust in the depressions and 'lapping' up the sdie nearest the camera that's ...

nereid,
Thank you for your considered answer!

John

13, your example of the shuttle is appropriate. I read, and it seems more than likely, that unless the promise of funding and opportunity for NASA to go to the Moon again soon, like in the next ten years, most of those with the experience of the Apollos will be dead. An enormous storehouse of expert...

All, In contrition for having hijacked the thread, may I offer Archimedes' Screw for discussion? This is a much simpler mechanism than the Antikythyra, indeed it is difficult to see how this could have been lead up to by earlier, simpler devices. Can anyone suggest an earlier, simpler device than th...

GG, All, Irony is not entirely absent from the Bible, there are some instances. I cannot tell if they were provied by a god or not. Job suffered mightily from the cruelty of Jehova, and lamented mightily too. He was upbraded by his unsympathetic neighbours, who quoted the prophets and the holy law t...

Ken, Thank you! What an interesting and informative paper! It raises a Q for me - Assuming that grooves are just crater chains below the resolution of the photos, the authors suggest that ejecta from Mars impacts caused these markings. Does (do?) 'ejecta' leave the impact site as a 'line of gravel',...