Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Putting An Observatory On The Moon's 'Dark' Side

timothy posted more than 12 years ago | from the harsh-mistress-good-vantage dept.

Space 314

wytcld writes: "CNN reports astronomers are pushing for a radio telescope on the 'dark side of the moon' (do real astronomers call it the 'dark side,' when it gets plenty of light?). The proposal by Yuki David Takahashi is amazing mostly because a guy just starting work on his Master's is managing major press for it. Still, a nice dream."

cancel ×

314 comments

Sorry! There are no comments related to the filter you selected.

A message from Linus Torvalds: Please Read (-1)

WeatherTroll (529760) | more than 12 years ago | (#2792408)

Hello Slashdotters, Linus here. Over the last 10 years we have done a great job in making Linux into an amazing operating system. We still have a ways to go if we want to defeat Microsoft, but I have no doubt we will get there if a major problem is dealt with.

This major problem is Richard Stallman (aka RMS). For years he has been the thorn in Linux's side. First, it's bad enough that he insists that everyone call Linux, GNU/Linux, as if he had anything to do with the initial creation or naming of Linux.

That isn't the biggest problem. The biggest problem is his appearance and attitude. The guy admits to being a goat fucker [geocities.com] . Who is going to take someone who says that seriously? Stallman hasn't bathed in decades. Who is going to want an operating system from someone who hasn't bathed in 20 years? As much as any of us may hate Bill Gates, he takes a shower every day, and that helped Microsoft be in the position it now is in. I am taking a shower every day to help Linux. Are you?

Stallman plucks dandruff out of his hair while he talks to you. That alone has got to turn you off Linux.

Stallman can't even clean up after himself [geocities.com] . This is equally true in his code just as much as he leaves used condoms all over the place. Frankly, his homosexual behavior and sex with goats that leaves all of these used condoms all over the place is simply unacceptable and makes Linux look like a joke. Please don't take this the wrong way. I have nothing against homosexuality (although having sex with goats is just plain sick) except when it interferes with Linux.

In conclusion, I am tired of Dirty GNU Hippies like Stallman causing problems for Linux. He must be stopped at all costs. I call on the Slashdot community to rise up and reject Stallman. Do it for Linux!

Heh. Guess this will add new Floyd meaning (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792409)

"And everything under the sun is in tune, but the sun is eclipsed by the moon!"

ep (-1)

bitchslapboy (193543) | more than 12 years ago | (#2792412)

This early post for Ida!

Earth? (1, Interesting)

Anonymous Coward | more than 12 years ago | (#2792419)

I see an issue: talking to it - the moon is in the way.

but, maybe if earth's radio broadcasts interfere with radio telescopes in someway, this would avoid that

Re:Earth? (0, Interesting)

bitchslapboy (193543) | more than 12 years ago | (#2792447)

If this thing could be contructed, then it means putting an antenna array in a precise location using robotic equipment. The ability to do this requires a telemtry infrastructure that could easily be used after the construction is over to transmit the data to Earth for analysis. There are any number of ways to do this. Most likely the plan calls for satellites orbiting the moon to transmit the data to Earth. They could also lay fiber optic cable across the surface of the moon to a relay station in view of Earth.

Re:Earth? (1)

IsaacW (543020) | more than 12 years ago | (#2792534)

A good point...

They might have to put some kind of repeater on the surface of the moon or perhaps in orbit around the moon. This would be a pretty simple procedure, but would likely add significantly to the probably huge cost of any project like this.

harha (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792421)

Yo mamma so old and tryin-to-be-trendy.. that I told her to act her age, and she died.

The name... (4, Funny)

vandelais (164490) | more than 12 years ago | (#2792422)

Instead of say, the Hubble, they should call it "The Floyd"

-1 -1 -1 (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792430)

come on, did you really think that was funny when you typed it?

Re:-1 -1 -1 (1)

DickPhallus (472621) | more than 12 years ago | (#2792531)

Did you really think that was witty when you typed it?

+5, Funny (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792449)

I'm sure this'll be modded up to that soon. Very clever.

Re:The name... (4, Insightful)

kzinti (9651) | more than 12 years ago | (#2792501)

``There is no dark side of the moon really... as a matter of fact, it's all dark.'' - Pink Floyd, Dark Side of the Moon

Re:The name... (0)

Anonymous Coward | more than 12 years ago | (#2792513)

Talking about the Hubble ... , does anybody of any recent LINUX versus WINDOWS 2000 Server study as thorough, well documented, and objective as the somewhat dated but relevant "Microsoft Windows NT Server versus UNIX " report by John Kirch found at http://www.linuxfocus.org/English/May1998/article4 1.html ?

gravity (1, Funny)

Anonymous Coward | more than 12 years ago | (#2792428)

This will be very interesting since we only see the same side of the moon due to gravity. More interesting would be an observatory headed for a black hole...I'd volunteer.

If you're a RADIO astronomer, yes... (5, Informative)

brassman (112558) | more than 12 years ago | (#2792431)

... the far side would be the dark side as far as you're concerned. The amount of radio crap we're spewing makes the work those guys are doing even more amazing, and sticking a robot observatory on the far side of a stable platform like Luna could produce some really cool results.

Remember, the money isn't spent in space -- it's spent right here on earth in order to get into space.

Re:If you're a RADIO astronomer, yes... (0, Troll)

CTho9305 (264265) | more than 12 years ago | (#2792446)

How exactly do you talk to something when there is a big ball of rock between you and it?

Re:If you're a RADIO astronomer, yes... (-1)

bitchslapboy (193543) | more than 12 years ago | (#2792458)

Two tin cans and a very long piece of string.

Re:If you're a RADIO astronomer, yes... (1)

aka-ed (459608) | more than 12 years ago | (#2792461)


Transmitter in lunar orbit would be nice. Relays along the lunar surface would be cheaper though. But it ain't that tough a nut.

Re:If you're a RADIO astronomer, yes... (4, Insightful)

dead_penguin (31325) | more than 12 years ago | (#2792492)

Can anyone speculate how easy it would be to sustain a stable orbit around the moon for long periods of time?

IANAAP (I am not an astrophysicist), but I would imagine that the influence of the earth's gravity on an object orbiting the moon could destabilize a satellite's orbit rather quickly.

Re:If you're a RADIO astronomer, yes... (2)

gilroy (155262) | more than 12 years ago | (#2792511)

Blockquoth the poster:

I would imagine that the influence of the earth's gravity on an object orbiting the moon could destabilize a satellite's orbit rather quickly.

Not any more than having the Moon there disrupts Earth satellites. Of course the three-body problem is harder than if the other gravitating mass wasn't there. But if you're in close enough, the Earth's effects would be a minor pertrubation.

Re:If you're a RADIO astronomer, yes... (1)

PeeOnYou2 (539746) | more than 12 years ago | (#2792556)

I really don't know, so I guess I'd believe you since you SEEM to know but,

It makes sense to me that it would be harder to keep an object in orbit around the moon, being that the Earth is so close, and so much larger... perhaps harder isn't the word, but the path would be much different than one in orbit around the Earth would it not?

Just wondering..

Re:If you're a RADIO astronomer, yes... (2)

AJWM (19027) | more than 12 years ago | (#2792597)

Not any more than having the Moon there disrupts Earth satellites.

Well, considering that the Earth masses about 81 times as much as the Moon, then yes, it does have something more of an effect on Lunar satellites than the Moon does on Earth satellites.

Another major consideration is that the Moon's gravity is less uniform -- you can't simply treat it as a point source at the Moon's centre except as a first approximation. There are what're called "mascons" (mass concentrations) under some of the maria which have locally slightly higher gravity than lunar average. Messes up the orbits a bit.

Re:If you're a RADIO astronomer, yes... (1)

steveg (55825) | more than 12 years ago | (#2792624)

Put it in a Lagrangian point. L5. That's as stable as you could ask for, and should be able to cover a good chunk of Farside.

Re:If you're a RADIO astronomer, yes... (1)

Fifth of Five (451664) | more than 12 years ago | (#2792582)

No need- the idea seems to be to actually plant the observatory on the moon itself, so orbital mechanics are not an issue.

Advantages? (0, Redundant)

The Great Wakka (319389) | more than 12 years ago | (#2792433)

What would the advantages of this be? I can't think of any right off the top of my head. And wouldn't something in orbit around the moon also be in orbit around the Earth, so you'd have to compensate somehow? Keep in mind, also, that the moon rotates too, so you'd have to keep a lunosycronous (wow!) orbit.

Re:Advantages? (1, Insightful)

SonCorn (301537) | more than 12 years ago | (#2792441)

If you had read the article, you would see that the advantages are that the moon would shield the telescope from garbage radio transmissions from Earth and that we would be able to detect emmissions that our atmosphere blocks. Also it would be built ON the moon not orbiting around it.

Re:Advantages? (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792453)

Tell me: are you an orbital mechanics Ph.D. trolling on slashdot, or are you really totally clueless on the subject?

Re:Advantages? (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792464)

Read the article, moron.

Re:Advantages? (1)

PhuCknuT (1703) | more than 12 years ago | (#2792535)

They're not talking about putting it in orbit around the moon, they want to put it ON the moon. Also, off the top of my head without doing any math, I'd guess that a "lunosynchronous" orbit would be impossible, I think the orbital radius would be the same as the distance to the earth...

Plaragey Leinghenzing Proassts (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792434)

Back by unpopular demand, page lengthening post.
1 [goatse.cx]
1
5
a
3
f
v
b
s
a
d
b
f
s
4
5
y
h
j
u
4
5
0
4
'
1
a
f
z
n
a
q
e
g
n
m
j
f
a
z
a
d
p
i
u
g
e
v
`
k
j
m
,
b
v
c
d
q
1
q
w
s
c
v
b
n
m
h
t
t
6
y
u
k
l
G
F
D
D
S
A
X
C
V
B
N
d
f
b
f
d
7
4
4
g
b
d
f
g
d
f
g
4
f
d
s
a
c
v
b
n
h
g
f
e
f
g
h
j
9
k
,
j
p
[
j
f
v
d
d
w
d
f
g
b
c
d
d
s
f
g
2
3
r
f
g
s
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
v
r
5
b
f
q
1
1
5
7
4
g
f
d
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
j
m
l
,
.
;
o
t
e
6
d
1
5
7
4
g
f
d
s
f
g
d
2
f
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
,
.
;
o
t
e
6
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
;
o
t
e
6
g
b
h
j
m
l
,
.
;
o
t
e
6
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
d
5
7
4
g
f
d
b
f
w
d
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
v
r
5
b
f
q
1
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
d
1
5
7
4
g
f
d
s
f
g
d
2
f
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
1
5
7
4
g
f
d
s
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
,
.
;
o
t
e
6
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
1
4
g
f
d
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
,
.
;
o
t
e
6
;
o
t
e
6
g
b
h
j
m
l
,
.
;
o
t
e
6
1
5
7
4
g
f
d
s
f
g
d
2
f
v
r
5
b
f
q
1
e
d
f
g
b
h
j
m
l
o
t
e
6
d
a

Re:Plaragey Leinghenzing Proassts (-1)

cockeater (542284) | more than 12 years ago | (#2792482)

I'd like to kick your ass one day. I'm sure at least one slashdotter lives near you..

Re:Plaragey Leinghenzing Proassts (0)

Anonymous Coward | more than 12 years ago | (#2792521)

I will just take all the numbers off my house asswipe! Try to find me then!

For you lazy people ;-) (4, Insightful)

CTho9305 (264265) | more than 12 years ago | (#2792436)

The article says this is good because the moon would shield the telescope from your satellite TV and internet access interfering.

Of course, it doesn't mention how exactly they plan on communicating with it! Sure, radio from the earth / reflected off the earth doesn't interfere, but important signals are also blocked.

Re:For you lazy people ;-) (1)

SuzanneA (526699) | more than 12 years ago | (#2792467)

I imagine you'd locate the radio telescope as close to the deliniation between 'blocked radio' and 'not blocked radio' and run a cable/fibre to a remote radio transceiver.

Another option would be a series of small radio repeaters that get to a high power antennae eventually.

Another, option is to have a moon orbit satellite system that relays the signals back, yes it negates the point of having a telescope on the moon a little, but in that situation you get to control what areas of the radio spectrum the satellites occupy, and don't have the same problem of interferance from random sources as with earth's orbital junkyard.

You may think the satellite solution is cheaper, but its probably not - if you're building a telescope complex on the moon anyway, building a second building a few hundred miles away + solar array for the cable repeaters and transceiver. Isn't much more work in relation to the telescope. Plus satellite orbits need replacement satellites every few years or fuel to maintain the orbit, a ground radio link base would be far cheaper to operate in the long term.

Comm Sat (1)

trip11 (160832) | more than 12 years ago | (#2792470)

What if you put a Satelite in a polar orbit on the moon, it could store data on one side, and transmit it on the other side as it goes around. Might be a little slow but it would work. Or maybe a network of a few Satelites would work better, depending on how much money you want to spend.

Penis? (-1, Troll)

Anonymous Coward | more than 12 years ago | (#2792439)

Dear sirs,

I would like very much for you to all place your penises, one by one, into my mouth, whereupon I will suck most vigourously on them until you ejaculate down my throat. While you wait, feel free to use my anus to pleasure yourself, but do wipe your penis clean before you place it in my mouth.

Sincerely,
Klerck

Re:Penis? (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792480)

Hey Klerck, werent you IP banned or some funky shit?

Re:Penis? (-1)

Klerck (213193) | more than 12 years ago | (#2792551)

Yes, I was, but as you can see, I have plainly gotten around that. And I suppose I could give one page lengthening post for the road! In all honesty, I'm kind of page-lengthened out today. I've been doing this for 24 hours straight!

Back by unpopular demand, more random number crapflooding!

3 [goatse.cx]
2
6
2
3
3
6
6
2
5
8
4
6
5
6
2
2
8
6
3
7
1
9
4
1
6
7
4
4
5
1
9
6
7
6
5
1
6
2
9
5
8
3
3
6
9
2
7
3
3
3
8
6
9
5
3
5
4
7
5
8
6
7
5
8
6
8
4
6
1
3
4
9
9
5
2
8
5
5
1
2
2
6
8
9
9
3
2
9
4
3
7
5
9
5
7
9
7
7
5
1
4
5
7
5
3
8
5
2
2
1
1
1
9
8
2
3
7
4
1
2
2
2
9
1
7
5
5
3
5
7
4
1
9
1
6
1
6
9
6
8
8
9
9
3
8
2
4
7
8
9
9
2
8
4
3
8
4
9
1
1
8
2
5
6
3
5
1
3
9
4
7
3
2
7
9
6
1
3
8
6
8
2
5
9
4
7
1
3
2
2
5
3
6
3
3
4
3
8
7
9
6
2
8
5
5
8
9
6
8
6
2
5
3
5
4
5
9
5
5
2
3
7
3
8
5
9
4
9
5
1
4
9
8
6
1
6
3
3
1
6
1
8
3
1
8
3
5
3
1
2
1
5
9
6
4
8
2
6
8
5
6
5
2
6
5
7
9
5
4
1
5
8
7
4
2
1
9
8
3
6
2
1
8
4
9
6
4
6
4
9
9
5
4
4
2
4
7
9
4
6
3
6
2
7
1
6
1
2
9
3
2
7
1
2
5
5
5
4
6
9
9
9
4
8
9
9
6
9
6
2
1
4
4
7
4
3
1
8
4
6
4
8
2
5
4
5
3
5
9
8
3
7
7
7
6
4
9
3
6
4
9
1
3
9
7
3
9
2
4
5
8
8
4
3
4
7
5
4
6
4
2
3
1
5
3
4
4
4
6
7
9
7
7
3
2
6
3
5
2
5
5
1
8
5
8
3
3
4
4
7
8
2
4
9
4
4
3
4
8
5
9
8
2
7
1
6
5
7
1
8
4
1
8
7
7
8
5
5
9
2
1
9
9
5
1
7
2
1
7
1
6
3
3
2
2
8
2
1
6
9
1
9
7
7
2
7
4
4
3
8
5
9
4
6
9
7
9
6
2
7
3
7
5
3
9
2
7
9
5
8
9
1
5
1
5
5
8
8
2
8
5
7
8
2
9
6
4
3
4
1
4
1
5
2
9
4
5
9
3
7
1
4
2
5
8
1
4
7
9
7
8
4
3
1
4
3
6
3
9
3
7
5
1
1
2
6
6
3
8
2
1
5
6
7
7
7
1
3
3
7
5
9
6
1
1
2
4
8
4
8
4
5
2
1
3
8
1
5
9
9
7
9
9
6
5
1
4
2
3
9
5
9
5
9
7
6
6
7
8
1
2
9
4
3
9
3
2
6
6
5
5
1
6
7
8
7
1
1
9
1
6
3
2
2
5
1
3
7
3
6
1
3
6
9
5
8
8
1
5
7
4
6
6
5
5
7
7
5
1
3
3
4
1
1
7
1
3
5
1
2
4
6
9
4
8
7
9
9
8
6
3
3
2
7
9
4
9
5
9
3
8
6
1
8
5
3
1
4
7
3
6
9
7
2
2
3
5
8
2
4
8
2
5
9
9
2
9
6
3
1
7
6
3
4
1
5
4
3
9
3
3
7
2
5
7
5
6
1
5
5
4
7
3
5
1
9
7
8
4
8
3
8
9
3
1
9
9
7
1
3
7
1
1
2
3
8
3
9
7
1
2
5
7
7
2
9
6
5
5
7
2
3
9
8
1
8
8
8
9
6
7
6
7
1
5
4
2
3
7
7
9
2
2
6
4
2
1
7
6
8
1
6
4
5
4
1
7
4
2
6
2
8
7
1
4
2
5
2
1
9
3
5
6
6
5
7
8
3
4
3
5
9
5
2
5
7
8
8
2
3
4
4
1
1
8
2
4
3
5
3
2
3
7
1
2
9
6
8
5
8
9
2
1
3
6
8
9
5
3
6
3
8
3
2
8
3
4
5
3
3
2
3
4
9
9
3
1
8
7
8
6
9
4
7
8
5
5
1
4
5
6
3
1
1
1
7
4
3
9
5
6
7
5
6
3
8
3
1
9
2
7
5
3
9
2
9
6
9
6
8
5
7
4
1
2
4
7
5
1
5
6
2
3
3
9
3
2
4
6
2
4
8
9
7
4
3
8
3
7
8
9
1
9
4
9
6
7
1
3
7
7
8
9
3
2
8
5
5
3
4
9
8
8
4
5
6
6
5
1
3
2
1
3
4
2
9
7
5
5
7
8
1
2
6
8
1
7
7
2
2
3
8
5
7
7
6
2
9
9
2
6
8
7
7
7
6
5
1
7
8
4
1
9
4
9
4
6
5
4
9
2
2
2
4
4
8
8
2
6
7
4
7
6
7
5
5
7
7
2
5
6
5
2
1
6
1
8
6
4
9
7
5
6
3
4
8
6
2
5
5
1
1
3
8
7
3
3
2
3
3
4
3
8
9
6
8
7
6
7
4
4
2
5
3
7
8
5
3
2
2
5
2
8
8
8
2
8
3
1
3
4
1
5
4
9
7
5
3
5
3
9
2
8
2
9
5
8
1
5
6
5
4
5
2
9
2
1
9
3
8
3
4
7
5
5
2
3
7
4
5
1
5
5
2
6
1
3
4
9
8
8
3
8
6
6
2
2
6
7
1
1
2
2
1
5
1
7
9
6
3
6
8
9
4
3
8
6
7
7
2
4
2
2
2
3
5
3
2
6
1
5
3
5
3
5
7
9
4
5
2
3
8
7
3
3
9
1
5
7
7
2
1
4
9
7
5
9
9
7
6
3
8
7
9
8
7
2
5
6
3
7
1
6
2
7
9
3
3
1
7
1
1
9
1
9
6
9
3
5
4
1
9
1
5
9
1
7
1
2
7
3
3
7
3
5
9
1
6
3
7
9
1
6
7
3
3
6
6
8
2
5
1
5
6
8
9
3
5
9
5
6
3
9
6
5
9
9
3
8
7
7
2
1
1
7
1
6
9
6
8
9
1
5
9
4
1
2
7
3
8
1
4
8
3
9
6
8
3
1
9
3
2
4
8
9
7
4
2
5
5
1
4
4
8
3
3
3
4
6
4
2
2
3
2
4
7
4
7
8
3
4
4
1
3
6
1
4
3
5
5
7
2
2
4
5
7
7
1
3
4
4
5
5
7
7
9
4
1
2
2
5
8
4
5
8
1
9
4
3
1
3
3
1
9
9
8
6
3
4
9
2
4
1
7
4
7
7
7
7
1
9
2
6
7
5
7
4
1
5
2
9
6
2
3
3
4
5
7
1
3
3
8
6
9
7
9
9
9
7
2
1
7
3
6
2
7
9
7
1
5
7
7
6
1
9
5
5
9
7
4
5
9
9
8
8
1
5
2
7
9
4
3
1
5
8
9
4
2
2
2
1
9
7
7
3
4
6
6
5
7
6
2
1
8
8
1
5
6
2
7
6
6
6
4
4
4
4
2
5
4
2
6
8
7
2
5
1
9
2
5
1
1
1
6
6
2
2
6
9
8
4
9
7
8
2
2
1
3
5
7
4
2
6
1
6
4
7
2
9
7
9
1
4
4
8
1
9
1
2
8
7
7
4
7
1
9
3
3
6
4
6
9
6
8
6
8
5
2
2
2
5
8
8
3
1
8
1
5
4
8
2
2
2
7
8
2
3
7
1
1
5
9
7
2
4
9
2
9
3
9
9
6
9
8
5
1
3
4
6
8
9
9
3
8
9
8
2
2
4
6
4
7
9
4
7
7
8
3
1
5
5
9
8
4
9
3
6
2
1
7
3
9
5
2
6
6
2
7
8
3
9
7
4
5
3
4
9
3
6
6
9
2
9
9
6
4
6
2
7
8
4
2
7
2
1
3
8
4
1
3
4
4
3
7
1
2
8
3
4
8
9
1
8
2
3
3
2
6
3
3
2
9
8
2
7
1
3
5
5
3
4
3
1
5
6
2
7
8
8
2
4
4
7
6
3
4
1
8
9
1
6
1
7
4
7
3
7
7
7
8
5
9
2
4
4
2
6
9
8
6
7
8
5
8
2
5
8
8
1
2
3
9
3
8
4
3
1
3
9
5
5
5
1
9
2
2
5
9
8
8
8
2
4
1
1
3
1
9
4
9
5
1
2
4
2
4
8
9
4
8
4
2
7
5
5
2
6
5
5
1
1
4
1
4
7
3
7
3
1
5
1
8
8
1
3
7
1
7
2
3
5
6
2
5
3
6
1
4
7
1
4
5
9
3
9
7
6
4
7
3
4
7
5
8
6
3
3
3
9
8
9
6
2
3
9
8
6
1
5
6
4
6
1
7
3
6
4
5
7
7
5
8
9
7
2
4
7
5
4
5
7
5
5
2
4
1
6
7
4
1
3
1
4
5
2
1
7
4
5
1
4
9
5
4
7
1
8
5
9
2
1
8
2
5
7
6
4
3
8
3
1
2
9
9
9
1
1
9
9
7
9
1
8
9
5
5
9
9
6
6
7
5
2
8
5
7
1
6
9
5
6
5
4
3
9
3
6
1
4
3
4
2
4
5
2
1
8
8
8
3
6
5
9
4
6
8
6
5
7
9
3
6
2
2
6
1
5
4
8
4
7
9
9
3
6
3
3
6
6
9
3
2
1
3
3
9
5
4
1
9
8
6
4
7
6
2
3
2
9
7
5
7
6
8
2
3
9
5
8
4
1
4
5
1
1
8
4
2
1
5
8
4
4
6
6
7
5
8
3
4
4
5
5
3
5
4
8
4
4
3
5
8
1
6
5
3
4
2
4
3
2
4
1
9
1
6
5
7
9
1
8
3
7
8
3
2
1
2
3
4
5
2
7
1
4
5
2
1
6
1
8
1
2
7
2
4
7
5
7
3
2
9
8
8
1
3
5
9
4
9
9
1
3
4
5
1
8
4
1
9
8
8
4
1
5
7
6
7
8
1
4
1
9
7
3
4
9
6
8
9
1
2
5
3
9
8
4
1
3
5
7
7
9
7
2
6
8
2
8
9
8
9
2
5
1
2
6
2
3
7
4
7
3
1
7
1
3
3
8
3
7
6
4
2
6
9
4
7
3
2
5
3
3
3
6
2
8
9
1
9
5
6
2
4
1
9
5
2
8
8
8
8
7
8
3
8
5
5
2
9
4
9
8
8
6
1
5
2
2
4
3
9
7
6
3
8
2
7
7
6
2
1
4
4
8
9
6
7
4
2
4
9
6
6
1
3
5
4
1
5
9
4
9
7
6
3
6
4
7
9
2
5
5
9
4
3
7
7
1
1
5
9
7
8
9
1
8
5
2
6
6
6
9
4
8
2
2
2
4
2
3
6
6
3
3
7
9
1
1
9
2
1
4
3
1
9
5
8
1
4
5
2
2
8
8
7
9
8
1
2
7
8
5
7
6
2
3
3
6
7
7
8
5
3
1
6
6
2
9
4
5
6
8
7
8
4
8
3
6
5
7
3
9
3
5
8
6
2
6
9
8
5
4
1
3
3
2
9
5
6
4
2
4
4
5
1
6
4
2
2
2
5
2
2
7
8
9
6
4
5
9
6
3
7
2
7
4
8
2
8
8
4
9
5
4
5
9
3
8
7
1
5
6
1
4
6
7
3
4
2
6
4
1
9
5
2
4
6
6
2
5
3
2
5
3
1
4
2
3
9
2
4
9
4
8
6
8
7
6
2
7
6
3
4
1
4
3
3
8
9
6
8
3
3
5
5
8
7
5
1
8
9
3
2
6
8
3
8
9
1
4
2
1
6
2
3
4
3
8
4
4
3
3
7
6
3
7
9
8
7
5
4
6
4
5
2
5
5
2
5
6
9
3
7
9
4
5
5
2
3
9
8
3
6
9
4
9
1
6
2
8
3
6
7
8
6
9
1
8
2
5
2
3
9
1
2
2
4
5
8
2
8
5
5
5
8
1
3
9
9
6
1
2
4
4
1
7
5
4
5
9
3
7
9
4
8
3
3
2
3
2
2
7
8
3
4
5
6
5
7
6
4
2
6
7
6
2
9
8
7
7
3
9
9
7
9
9
4
8
4
1
1
1
9
9
9
7
9
6
6
5
9
4
9
6
1
4
3
5
4
3
7
9
7
5
2
3
1
2
7
9
9
5
3
8
8
9
2
6
7
7
4
6
5
4
8
3
1
8
3
6
6
9
2
9
6
1
3
1
6
7
8
1
9
1
7
3
3
8
6
6
9
7
4
5
7
5
2
3
8
4
4
8
2
9
4
5
1
8
9
5
4
7
2
8
3
4
4
2
5
1
5
1
7
5
6
9
4
2
7
7
9
5
9
7
8
4
6
3
9
8
8
8
8
9
4
4
2
5
1
1
5
4
4
9
6
7
8
4
4
9
9
6
8
6
7
5
4
7
3
5
4
5
5
3
4
5
9
1
3
4
6
8
2
7
4
7
9
2
3
6
3
6
6
7
8
8
3
5
9
2
1
1
9
5
2
1
5
2
3
8
6
7
6
6
6
9
1
3
4
5
5
8
7
8
4
9
8
1
7
8
4
6
7
3
5
1
8
2
9
1
5
1
7
2
6
4
5
3
6
9
4
5
3
5
4
3
1
8
6
1
5
1
6
5
9
5
1
1
8
9
2
1
8
3
9
8
3
9
9
9
7
6
4
8
1
1
5
7
4
9
4
4
2
6
4
9
1
7
5
7
9
4
7
4
3
1
6
9
8
7
5
2
7
5
4
3
8
7
4
6
6
2
3
1
6
3
3
6
2
6
7
1
9
9
5
3
9
7
1
6
8
3
9
7
4
3
3
3
7
4
7
9
5
2
6
7
3
2
6
9
4
9
7
5
5
1
7
9
2
2
2
7
6
2
2
7
9
6
5
3
1
1
6
4
1
9
7
5
2
7
4
1
2
3
7
4
7
4
9
2
4
9
2
6
3
6
2
8
8
6
5
7
2
9
5
4
5
3
8
1
8
6
7
6
4
2
7
9
2
7
7
4
4
4
7
6
3
3
8
1
5
6
4
5
9
5
2
4
7
2
1
3
5
6
7
2
3
9
2
6
3
1
8
8
9
7
3
2
8
6
6
9
9
3
7
6
9
4
6
9
6
5
5
2
7
1
6
5
2
8
5
9
5
2
1
3
3
3
4
6
8
2
5
8
8
2
5
4
2
9
7
4
8
7
3
9
7
3
7
5
2
8
3
9
3
2
9
4
1
3
2
5
2
2
1
9
4
7
4
6
9
5
9
9
5
8
3
4
6
4
7
7
5
7
6
2
8
1
4
8
3
6
3
7
6
2
4
5
9
4
4
2
7
1
8
1
4
4
2
4
7
4
4
3
5
2
4
1
3
9
4
8
3
2
2
1
2
1
6
2
9
1
6
7
6
7
2
1
5
5
4
5
9
6
2
8
9
3
7
1
3
2
1
9
6
8
6
2
3
7
8
9
1
9
3
7
3
8
7
2
4
5
5
2
4
9
6
8
5
3
7
1
5
1
8
9
5
6
1
3
1
7
6
7
4
8
7
2
2
8
5
4
9
3
2
6
2
8
4
4
7
6
9
4
4
3
5
2
4
4
7
6
4
6
1
1
5
6
1
5
3
2
5
1
1
1
5
8
2
9
6
3
7
4
4
1
7
1
8
9
1
9
6
1
6
2
6
5
1
6
3
7
8
4
7
4
6
5
8
2
6
2
5
3
5
3
2
9
8
3
9
4
1
1
7
1
8
3
5
8
7
6
3
5
9
1
2
2
7
2
3
5
5
7
3
4
8
8
6
4
8
2
7
5
1
2
2
9
9
3
1
5
7
9
9
2
7
9
2
5
9
3
7
6
8
7
4
6
1
4
6
3
8
7
8
9
4
5
9
6
7
4
5
8
9
7
7
7
1
4
7
6
5
6
9
4
1
3
6
1
9
8
1
6
9
6
9
8
7
8
4
2
2
5
3
8
7
7
2
8
5
1
9
8
5
4
9
4
8
5
5
9
5
1
7
2
7
2
3
2
5
9
8
6
4
8
3
6
5
3
8
2
1
7
2
9
5
6
2
1
8
6
1
2
2
3
8
4
4
2
5
5
8
2
6
8
2
8
6
1
2
5
8
3
3
9
8
9
2
1
1
6
8
1
8
8
8
2
7
2
9
9
9
6
8
8
5
8
9
4
4
9
5
5
1
6
4
6
7
6
2
6
7
6
6
5
2
6
6
5
1
3
1
1
4
6
1
6
6
4
7
5
5
2
3
5
4
2
9
1
7
2
9
9
1
9
4
5
3
1
5
5
4
2
4
9
4
9
7
8
8
5
5
6
2
6
8
4
6
8
4
6
6
8
8
4
3
1
1
1
7
3
8
9
8
3
5
6
3
4
4
3
9
9
2
8
2
1
7
9
5
6
6
9
1
7
3
3
5
7
3
1
7
9
2
6
6
3
3
3
2
2
6
1
5
7
7
9
6
1
5
7
7
1
1
9
3
4
7
1
3
8
9
5
2
5
6
4
2
9
4
9
7
5
6
4
1
9
3
1
7
7
1
2
2
7
1
5
6
7
7
9
5
4
6
8
4
3
8
6
3
3
3
1
1
1
4
9
6
9
5
9
7
2
7
2
9
6
8
1
7
5
1
3
5
1
3
9
6
2
8
9
1
9
9
7
4
5
6
9
6
2
5
3
9
8
7
6
4
5
6
8
3
8
8
2
1
1
2
3
4
6
5
8
3
7
2
7
3
4
6
1
4
2
7
7
7
1
5
1
8
9
3
7
5
7
2
3
3
5
4
5
8
1
1
7
9
8
9
3
1
4
1
4
5
7
3
8
4
5
2
9
2
5
9
8
6
3
7
7
8
4
8
3
6
7
2
8
1
5
7
5
3
9
8
7
4
4
7
5
4
7
4
8
5
4
6
6
2
8
6
3
6
6
5
5
1
3
1
2
1
5
3
9
2
2
2
2
3
2
7
5
1
8
4
9
3
8
9
5
7
9
8
8
7
3
2
2
3
5
3
9
1
5
2
3
3
8
2
7
5
3
5
7
2
4
6
1
8
3
4
9
3
2
5
9
4
3
4
5
6
5
6
1
7
8
9
3
9
1
2
6
7
5
4
9
7
1
2
6
1
6
2
3
5
8
4
4
8
6
9
6
8
4
5
3
8
1
7
1
3
6
2
9
6
4
1
5
3
1
9
6
4
7
8
5
6
8
4
3
8
9
4
3
2
9
4
9
9
5
4
2
1
6
5
3
6
8
2
6
8
7
9
6
9
9
7
1
8
9
4
4
8
4
5
9
9
9
7
5
9
6
4
3
9
4
3
1
3
3
7
6
8
8
2
6
8
4
5
5
8
4
8
3
3
6
6
5
6
4
7
6
2
5
3
8
8
2
2
2
9
4
9
2
5
8
8
6
9
8
1
7
3
4
8
4
4
5
7
6
4
1
5
8
7
6
4
3
1
5
3
1
1
9
8
7
4
4
9
3
2
3
7
5
9
4
9
7
7
6
9
9
1
8
8
3
9
8
1
2
4
8
4
4
7
4
4
1
2
2
4
7
6
6
6
8
7
8
2
3
3
6
5
8
8
1
5
2
9
8
6
3
4
6
9
5
1
1
4
7
6
3
1
9
4
5
1
2
9
5
7
7
3
5
1
5
8
7
3
6
2
2
2
3
2
5
7
7
3
3
8
5
6
1
2
7
2
8
1
9
4
7
3
2
3
7
4
5
6
8
4
3
6
7
4
6
1
1
9
5
4
9
5
1
6
4
4
8
7
5
8
1
4
5
7
5
9
7
3
3
8
7
3
5
7
3
7
4
6
2
9
3
4
7
4
1
9
2
9
9
8
1
7
1
4
8
2
8
8
3
9
2
2
3
5
5
9
1
5
6
2
4
8
5
6
8
7
5
8
2
6
5
9
5
5
2
6
2
5
7
4
7
2
2
5
1
8
2
3
2
6
5
3
1
3
2
1
7
5
9
8
7
7
1
5
4
1
3
1
5
1
3
7
3
1
4
1
1
5
6
6
5
2
6
2
2
5
1
6
8
5
2
9
3
2
7
5
7
9
7
3
8
9
8
1
7
6
6
1
5
1
4
1
6
9
3
2
1
1
8
8
1
8
4
7
7
7
4
9
5
2
6
3
1
4
4
4
4
9
4
2
1
9
7
7
9
7
3
3
5
7
5
8
2
4
7
6
7
6
2
1
2
9
8
1
2
1
3
6
2
9
4
2
5
2
5
9
9
9
2
1
1
6
4
1
5
4
3
9
8
8
5
9
1
1
9
8
5
8
6
1
2
6
6
3
5
5
7
6
1
9
7
8
4
2
5
4
5
5
8
3
4
1
6
1
5
4
1
6
2
5
5
2
3
9
8
4
5
6
3
8
7
8
6
3
4
6
5
2
2
6
6
7
8
4
2
7
2
8
7
9
7
1
9
7
6
6
3
4
4
4
1
3
9
4
4
2
8
7
1
6
9
8
7
8
7
3
7
5
6
7
8
9
5
4
7
4
4
8
8
2
2
2
4
8
5
8
6
2
4
5
4
4
6
1
8
4
7
3
7
9
3
8
2
3
3
3
9
8
8
5
1
1
9
7
7
5
5
1
8
9
1
6
4
8
2
3
1
8
6
1
6
9
5
2
1
7
7
6
9
3
4
8
4
9
2
5
2
4
9
8
2
1
8
6
6
7
1
9
3
9
5
5
3
6
6
1
7
7
6
3
8
1
8
8
1
7
6
2
1
2
6
5
5
1
5
7
3
3
8
1
8
4
4
6
8
5
2
9
4
1
8
2
2
5
1
1
3
3
1
2
6
3
5
5
1
4
2
7
7
9
6
9
4
8
7
5
4
2
5
2
5
8
7
1
9
2
8
8
9
8
4
1
4
6
2
1
7
8
7
8
4
6
5
6
7
2
7
8
4
4
2
7
6
5
9
5
4
9
7
7
7
4
8
1
9
3
5
3
4
6
5
2
1
6
3
1
1
4
8
1
2
7
2
9
9
6
1
1
7
9
9
9
8
4
3
5
7
6
6
5
5
5
2
6
1
2
1
6
7
2
4
3
6
4
8
7
4
2
7
3
4
4
9
3
1
8
6
2
2
6
4
1
5
9
5
7
3
9
4
7
6
8
8
2
5
7
7
3
3
5
2
6
6
3
2
2
9
5
1
5
9
6
2
9
9
5
1
4
9
3
4
2
1
5
2
9
2
8
2
8
1
4
4
6
7
7
8
9
1
4
8
6
9
4
1
9
7
1
2
7
8
3
6
7
2
5
1
2
6
1
2
7
5
2
4
1
3
1
7
1
4
9
5
2
3
4
6
2
6
5
9
7
7
9
9
3
4
3
8
6
4
2
3
1
9
1
3
9
4
4
8
1
3
5
2
1
6
1
4
6
4
6
7
2
1
1
8
5
8
4
4
9
2
7
3
2
6
5
5
1
5
3
1
5
3
3
5
1
2
2
8
3
8
8
6
3
4
3
1
3
2
6
7
4
9
8
6
4
8
3
1
1
6
3
7
2
6
8
6
8
5
4
2
6
8
9
9
1
3
7
4
6
6
5
8
8
5
6
9
4
2
3
9
3
4
5
2
3
3
1
8
6
6
1
8
6
3
9
9
5
4
2
5
5
7
6
5
9
5
5
4
5
7
5
7
9
5
4
5
5
9
3
1
7
5
6
8
1
7
5
9
9
5
6
3
1
2
9
3
4
5
9
2
2
2
8
8
3
4
2
4
3
9
1
6
5
6
1
1
5
6
3
1
5
3
3
4
6
7
5
4
6
8
8
9
1
8
9
3
2
5
4
4
6
2
3
5
3
9
2
6
8
8
1
2
8
5
1
6
7
8
3
6
7
5
5
1
2
7
5
3
4
7
2
8
1
8
2
1
8
1
9
4
9
2
3
3
6
5
4
8
8
3
4
8
5
5
2
4
9
7
7
9
8
1
1
4
7
3
9
6
3
9
7
6
5
2
5
5
9
8
7
7
5
7
2
4
5
1
9
5
8
6
5
8
2
9
2
4
1
6
9
9
6
7
6
8
8
3
4
3
8
1
3
2
7
5
4
9
8
9
2
9
8
4
1
4
6
2
4
6
3
6
2
3
3
6
7
7
7
4
3
5
6
4
3
8
7
2
1
5
1
7
2
9
7
2
7
3
7
7
5
7
7
8
6
1
7
5
8
4
6
5
9
4
5
1
6
6
5
1
4
9
7
8
6
9
8
5
6
4
9
8
4
2
5
8
4
6
6
6
5
5
6
5
6
7
6
5
4
9
8
3
6
1
8
5
3
8
2
5
7
1
4
8
3
2
8
2
8
2
9
9
5
3
9
7
5
3
4
5
9
2
6
3
6
4
7
5
7
6
2
5
5
8
7
9
1
2
4
7
9
3
8
5
7
1
4
7
1
8
1
1
8
9
5
4
7
7
7
5
7
1
4
9
1
7
7
1
6
2
2
8
6
8
7
1
4
4
1
9
8
2
8
1
8
3
3
5
4
6
6
5
3
1
5
5
9
6
4
7
1
2
5
6
2
5
7
8
3
6
2
1
3
7
5
4
6
3
5
3
4
8
5
4
8
2
5
2
1
5
1
6
3
9
3
6
7
3
1
5
2
3
9
8
4
6
1
4
3
6
7
9
8
8
2
7
7
5
1
2
1
1
7
4
3
7
8
6
2
8
3
7
5
5
5
5
1
5
3
2
6
5
7
5
1
2
3
6
2
2
1
2
4
6
8
6
9
7
1
3
9
8
8
7
5
4
5
4
3
1
3
1
1
6
2
7
7
6
8
7
7
4
1
2
5
4
5
4
9
1
7
6
9
1
7
7
3
5
6
2
7
3
5
5
8
5
5
9
4
9
8
2
7
3
4
9
1
9
9
2
4
5
2
3
7
7
8
2
6
1
8
7
1
9
3
2
1
4
8
1
3
4
2
2
5
8
4
6
7
3
7
1
1
1
9
5
5
7
2
3
7
4
7
3
8
7
4
6
6
2
6
7
9
5
8
9
2
1
3
2
7
8
8
7
6
1
1
5
6
8
3
2
4
1
8
5
8
2
9
7
3
6
9
9
3
5
5
9
7
2
7
2
9
8
1
3
1
5
1
7
8
3
1
1
8
6
2
8
4
4
7
1
1
4
8
3
9
5
3
6
3
5
9
9
5
7
7
4
6
3
6
6
9
5
5
4
8
4
6
8
9
3
1
5
4
8
5
2
3
8
1
6
9
7
6
6
7
9
3
7
6
3
7
3
7
9
9
2
2
4
9
3
1
2
2
4
5
5
6
2
7
5
3
8
1
6
7
8
4
3
5
3
4
5
3
7
6
1
6
8
8
9
2
5
7
1
6
2
8
8
7
6
9
2
3
9
3
8
4
4
3
1
3
7
8
4
1
7
1
7
7
5
2
6
4
5
2
9
3
6
6
4
8
9
2
6
3
7
8
9
5
4
5
8
6
4
3
4
9
9
3
2
7
8
7
5
8
8
7
1
1
9
2
2
1
5
5
6
7
6
6
7
2
3
7
9
8
6
4
7
3
1
8
9
3
8
7
3
7
2
7
2
3
4
3
9
3
7
9
8
4
3
1
1
1
9
9
2
1
1
9
5
1
7
2
1
5
8
9
1
9
5
6
5
1
2
3
4
8
1
1
4
2
9
5
4
3
6
2
8
7
1
3
9
4
7
5
8
4
1
2
9
9
7
6
5
7
3
8
7
9
1
7
5
1
3
6
9
2
6
7
4
4
8
5
2
4
4
8
4
8
6
8
2
6
3
5
8
5
2
4
8
2
2
7
7
9
5
8
7
8
4
2
1
5
4
9
7
9
6
2
8
6
6
1
5
3
5
5
7
2
9
1
5
2
1
9
8
9
3
4
4
6
5
7
1
5
8
5
6
6
5
2
6
5
3
8
2
3
3
8
3
5
4
4
4
7
2
8
2
2
8
4
2
5
8
3
2
2
7
2
4
6
7
8
3
7
6
5
2
8
6
9
2
6
1
3
4
8
8
4
4
4
2
2
4
9
6
3
3
2
6
3
7
9
8
8
3
8
8
3
8
8
2
8
3
6
1
3
9
5
7
6
6
7
4
4
4
3
8
7
3
4
4
5
2
8
9
3
9
4
2
4
9
9
4
7
7
8
7
5
9
4
3
4
1
9
2
7
5
7
7
9
6
9
2
7
5
3
7
1
8
8
9
6
8
8
3
3
6
8
9
7
7
8
4
7
3
5
2
2
6
3
7
4
7
9
8
6
1
6
3
8
1
9
9
5
9
6
8
3
7
8
1
8
4
2
6
6
4
8
6
1
8
9
1
1
8
5
1
1
2
1
1
2
3
4
4
1
8
1
8
4
2
1
5
6
9
7
8
2
3
4
5
1
2
8
6
9
7
2
7
5
6
9
5
3
3
8
7
7
2
5
8
8
1
2
6
1
8
4
8
9
8
1
2
3
1
5
9
6
3
2
8
9
5
1
6
6
6
9
8
2
3
9
3
6
6
6
9
2
1
8
6
3
8
9
5
9
7
3
3
5
9
2
8
4
7
3
5
1
3
3
9
8
8
4
8
9
4
8
5
8
4
6
8
1
3
4
4
6
2
2
7
5
3
7
9
8
4
8
5
8
5
3
8
6
9
5
5
5
6
6
6
1
3
3
4
9
1
1
1
2
9
7
9
1
1
3
7
1
9
2
2
4
2
5
1
1
1
5
3
5
3
9
5
8
9
1
5
1
4
1
8
4
2
9
2
2
6
6
4
5
5
6
5
6
6
8
4
8
5
3
5
6
2
4
9
2
2
3
6
5
4
7
2
1
8
6
7
5
5
7
9
2
3
2
6
4
4
1
4
5
6
1
1
8
5
6
3
6
1
6
3
8
2
1
9
2
6
3
3
2
2
4
9
7
6
4
5
8
1
1
5
2
1
4
1
3
6
8
4
4
4
5
5
7
3
8
9
5
5
7
7
2
2
3
4
9
3
4
7
4
9
1
1
4
4
9
4
7
7
4
2
1
2
2
8
1
6
4
8
2
4
4
5
8
2
1
6
8
9
2
7
9
4
4
4
2
5
2
3
8
2
1
6
3
4
6
3
5
6
5
2
7
6
7
5
3
5
9
2
9
4
9
2
8
4
4
5
1
5
8
5
2
7
8
7
8
1
5
1
4
6
1
9
9
9
2
9
9
8
4
2
9
4
3
2
7
1
7
8
6
6
4
4
1
3
3
5
2
9
7
7
2
4
2
1
7
5
4
6
8
2
9
8
6
6
1
7
5
9
4
3
5
5
4
4
5
1
9
4
7
1
9
1
2
3
5
1
2
4
8
3
7
4
2
9
8
2
1
7
1
2
5
1
3
8
9
3
1
9
6
3
1
8
2
4
7
9
4
1
4
1
2
8
1
1
1
4
5
5
6
6
4
5
9
2
4
8
7
9
7
3
8
6
1
3
8
2
8
8
7
8
6
5
7
2
9
8
5
6
4
7
6
1
2
6
8
6
9
5
8
6
1
9
5
1
5
3
2
1
2
8
7
5
2
6
5
3
5
2
7
9
5
7
9
7
6
8
1
1
4
5
8
3
5
9
9
9
1
6
4
2
3
4
7
9
1
3
8
8
6
1
6
9
2
1
4
5
7
3
3
7
4
7
1
8
8
8
1
2
2
7
4
4
8
6
3
2
8
4
6
8
2
4
2
6
5
4
5
7
5
6
3
4
6
7
9
3
3
1
4
6
1
5
1
6
4
9
6
2
8
8
6
7
9
6
2
9
3
1
6
7
1
3
9
2
2
8
8
1
6
2
1
3
7
5
4
6
6
1
9
9
9
8
5
7
3
9
8
1
8
8
6
5
1
8
8
5
4
4
8
1
5
3
3
7
6
5
4
6
3
5
1
6
5
5
3
2
9
1
8
2
4
5
6
5
3
7
6
5
5
9
3
7
7
2
8
5
8
6
8
5
4
6
3
2
7
1
1
8
5
6
3
6
3
5
4
6
5
1
4
1
7
4
3
3
3
1
2
2
8
6
3
5
1
7
1
8
3
6
4
9
5
1
2
2
3
3
2
3
1
8
9
2
9
9
8
1
5
6
4
6
1
6
2
9
5
5
9
3
8
7
2
7
2
2
8
2
6
7
9
3
8
2
2
7
8
1
6
2
3
2
3
8
8
4
8
5
8
5
4
4
8
6
3
7
2
4
5
9
2
4
5
6
2
7
8
1
4
4
5
8
6
3
3
3
1
7
6
4
2
9
4
4
4
2
4
3
9
7
1
7
7
9
5
1
9
7
7
9
3
6
7
3
3
3
5
4
6
3
1
7
4
6
7
6
1
6
2
7
7
8
5
4
8
5
2
2
4
5
4
4
4
4
5
8
4
2
7
6
3
8
8
8
6
7
3
1
3
3
3
5
2
1
1
5
8
6
3
3
5
2
1
6
4
1
7
9
4
5
3
2
7
2
9
7
9
4
5
8
8
2
2
2
8
8
2
6
5
9
8
8
9
7
2
9
2
8
3
4
8
6
7
1
9
6
5
5
6
4
9
4
1
1
4
4
3
7
9
1
6
9
5
3
2
7
4
9
9
6
1
6
2
5
1
2
8
2
1
9
1
9
6
7
1
5
6
2
6
1
5
8
8
8
3
2
2
7
4
7
1
6
1
7
2
9
1
2
2
3
5
6
2
2
3
3
7
2
5
8
4
2
6
4
6
2
1
8
1
7
9
4
9
1
6
4
9
6
2
9
5
8
1
4
6
1
5
2
3
1
1
1
6
2
1
4
7
2
1
4
2
2
2
2
6
2
2
2
9
1
5
4
4
9
9
7
3
2
1
2
1
7
9
5
1
5
3
1
6
6
1
8
4
1
9
5
6
7
6
7
4
8
2
6
1
3
1
2
6
5
6
6
8
1
1
2
6
6
7
1
2
7
8
4
7
5
8
7
1
5
3
9
1
7
5
9
5
8
6
7
6
6
9
2
9
5
6
9
7
9
3
4
2
9
5
3
4
6
6
3
4
7
6
4
9
6
3
8
9
4
1
4
3
6
5
7
4
4
3
6
7
8
9
6
6
7
6
7
9
1
7
8
7
9
7
3
9
4
6
7
2
2
2
5
3
2
4
3
5
6
5
3
8
4
9
5
7
1
1
3
1
7
2
6
4
9
3
9
6
3
7
7
5
6
1
3
8
5
8
7
6
2
2
6
3
9
3
2
2
7
1
7
1
3
2
9
2
7
3
3
2
2
6
7
4
4
4
9
6
7
7
2
6
8
7
9
9
6
2
2
3
1
2
3
7
8
5
8
3
1
6
9
8
5
9
1
3
6
8
6
3
3
7
9
8
4
9
6
1
5
7
7
6
1
1
4
1
5
5
9
2
5
6
2
5
1
5
5
1
4
1
4
4
8
8
6
5
4
6
4
3
6
8
4
6
5
3
5
8
8
2
2
7
1
5
6
1
3
1
4
6
4
1
4
7
9
3
9
3
6
9
7
6
5
4
3
9
4
4
4
2
1
9
5
3
7
3
7
7
7
6
5
3
5
8
3
2
4
7
1
3
6
7
5
6
3
4
4
3
2
9
2
8
2
9
8
3
9
6
5
9
4
4
7
9
2
7
3
4
4
2
5
3
6
1
5
9
1
7
2
2
7
4
1
9
2
9
9
8
4
2
2
9
2
6
8
8
1
2
3
6
5
6
7
9
1
2
1
6
3
9
7
6
8
7
6
3
3
1
9
6
6
6
8
4
3
4
3
4
5
6
8
5
6
7
3
5
3
9
9
1
3
4
9
3
9
1
1
7
2
7
3
5
4
2
5
5
3
5
1
6
1
2
1
8
2
3
3
6
9
2
8
1
3
4
4
2
5
1
6
3
3
1
9
9
2
5
6
7
6
8
1
3
8
5
2
3
7
7
9
1
1
8
3
1
1
5
6
6
3
1
4
2
4
7
5
9
2
6
1
6
5
1
4
2
6
1
3
3
5
7
6
2
6
3
7
2
1
2
1
3
3
2
5
2
6
3
4
2
3
9
4
5
7
4
2
1
6
4
9
6
5
3
5
1
5
9
2
1
5
7
8
1
6
6
4
2
6
4
9
6
5
7
7
5
9
7
2
3
6
3
2
7
8
6
8
6
5
7
7
9
7
2
2
6
3
6
4
4
9
4
9
3
8
6
9
7
6
6
6
8
4
1
5
7
9
8
3
7
6
4
6
8
7
2
9
8
1
7
2
8
4
4
8
6
2
7
5
5
9
3
7
4
3
7
2
7
7
9
3
6
5
5
5
9
3
8
6
4
2
4
1
4
1
8
4
6
2
4
9
8
2
3
7
3
7
3
6
5
6
5
2
2
4
8
8
9
4
5
9
6
1
2
9
1
3
6
5
3
3
2
8
8
2
9
5
6
8
1
7
7
9
3
7
4
5
3
1
6
1
2
3
7
7
4
3
3
9
5
2
3
8
7
5
7
4
6
6
8
1
8
7
4
6
4
7
2
2
7
8
8
9
4
5
1
1
3
5
9
5
7
5
8
1
4
6
1
4
8
6
3
9
2
6
9
4
1
5
6
9
5
8
9
8
5
3
3
5
5
3
9
9
6
7
3
9
4
4
8
8
2
9
9
5
1
2
8
8
1
9
3
7
4
8
7
1
4
4
5
7
9
1
1
3
4
4
3
2
7
7
7
8
9
3
8
6
4
8
4
3
6
5
6
8
5
5
8
4
9
1
8
3
5
9
8
6
3
9
7
8
6
8
6
8
7
1
4
4
4
6
3
9
9
3
7
4
7
3
3
1
6
4
2
9
6
5
2
7
4
2
7
8
7
5
7
8
9
7
1
4
5
7
9
7
8
4
6
3
1
7
2
9
7
4
2
5
7
9
6
9
5
7
4
9
7
4
5
5
9
8
2
5
5
7
3
6
1
7
8
4
7
2
3
4
2
1
8
8
4
6
6
1
3
2
8
4
6
4
7
1
2
4
8
4
9
9
4
7
8
1
7
6
7
5
2
8
4
1
6
1
4
5
8
8
1
8
7
4
6
5
7
9
5
7
5
4
1
9
6
9
5
6
9
1
2
9
1
8
1
1
9
1
6
1
3
2
8
8
4
4
5
9
1
9
2
3
5
3
9
8
4
4
6
7
9
8
8
7
8
7
7
2
4
9
5
3
4
4
9
1
3
9
9
2
7
2
7
5
4
3
7
6
6
2
8
4
9
2
6
5
4
3
9
8
9
4
2
1
2
6
3
8
7
1
2
7
3
5
2
2
9
1
9
2
2
3
4
4
1
8
3
8
8
2
9
5
5
1
4
7
2
1
7
9
8
3
9
6
2
3
8
2
6
3
5
9
8
2
7
9
3
9
7
6
6
7
9
6
9
8
7
9
6
7
8
7
2
7
4
6
3
3
1
8
8
9
8
9
9
2
4
8
8
8
1
8
3
6
9
9
2
9
7
8
7
6
7
6
9
8
7
6
7
8
5
4
3
2
5
6
1
4
9
8
6
3
4
1
4
7
3
1
9
6
2
6
5
8
7
4
2
7
3
5
5
8
1
2
3
8
7
8
8
4
6
1
2
8
4
4
2
2
9
6
7
9
4
6
8
1
3
2
8
4
1
9
8
9
3
1
9
8
4
1
2
5
1
3
6
3
5
4
1
1
3
1
4
6
1
6
9
8
2
1
1
6
4
2
6
2
3
9
3
5
5
2
8
6
8
6
4
7
5
7
2
6
3
1
7
6
3
7
6
6
3
8
4
1
3
9
2
5
7
4
8
2
6
4
2
6
3
3
9
8
9
5
7
5
1
2
7
7
5
2
3
2
4
6
7
7
6
3
1
8
4
8
2
2
8
1
5
6
3
4
8
7
8
5
1
7
3
8
8
6
8
2
4
1
2
2
2
3
2
6
8
5
2
7
9
4
3
6
1
3
9
2
2
4
9
4
1
7
6
3
9
7
5
3
8
6
6
3
9
4
7
5
9
7
1
7
2
2
2
5
4
3
6
7
4
1
1
9
3
4
1
9
9
4
2
6
3
2
1
6
5
9
8
1
5
1
2
7
8
4
6
4
8
4
5
3
1
8
9
7
1
7
3
3
6
7
1
8
3
5
5
6
2
1
3
3
7
6
3
9
5
6
3
8
4
7
6
5
2
5
3
1
9
9
1
4
3
3
9
4
8
3
3
2
7
3
8
4
5
1
4
9
5
6
9
8
7
6
1
2
8
4
9
4
6
8
8
3
6
8
9
6
3
5
8
8
1
3
3
7
3
4
4
1
4
5
9
7
8
4
5
2
8
1
6
5
2
3
4
8
5
7
9
5
3
8
3
2
5
8
1
6
4
5
5
5
5
6
9
3
1
1
9
2
2
1
3
5
7
5
4
2
4
1
6
1
2
2
4
5
9
4
5
4
4
9
3
1
7
1
9
2
7
1
6
2
5
7
5
2
9
6
6
8
5
9
9
3
9
6
9
5
4
8
5
7
1
3
5
5
6
3
2
3
6
9
5
4
2
5
9
4
2
4
8
5
9
9
1
8
2
2
8
3
2
4
3
4
7
9
8
4
6
4
9
6
7
3
5
4
1
3
7
8
4
4
8
4
6
4
8
1
7
1
3
6
6
1
1
2
4
9
2
3
4
9
7
2
9
2
7
9
7
1
5
7
7
6
2
7
5
7
2
7
7
2
8
5
9
3
4
3
1
3
9
4
8
7
6
6
7
1
7
1
9
1
3
5
3
8
9
9
1
4
8
6
9
2
2
1
7
6
8
6
1
7
3
5
1
8
8
9
2
3
3
6
1
1
7
7
5
8
2
8
4
3
4
2
5
5
5
7
7
9
7
2
2
6
2
5
5
4
8
2
5
5
6
5
7
8
1
3
1
7
6
7
1
7
4
4
4
1
8
8
6
3
6
7
1
8
9
2
7
2
4
3
5
6
3
2
5
5
4
7
7
3
5
8
4
4
3
5
5
9
5
8
1
2
3
5
8
5
8
2
1
9
1
7
7
1
1
1
2
1
3
2
4
9
6
9
5
1
2
6
8
2
1
2
1
8
5
1
6
9
7
7
2
3
9
5
2
4
5
6
7
2
3
2
3
2
8
9
6
6
1
1
2
3
5
7
3
8
1
4
7
1
1
3
5
6
9
2
3
3
8
4
8
1
4
8
5
7
3
6
8
6
4
5
2
1
3
2
5
4
3
3
5
9
1
7
2
6
6
7
7
6
2
3
4
1
2
1
8
2
6
2
5
2
2
4
8
6
5
9
6
8
1
4
8
5
6
9
8
8
5
6
8
8
6
5
7
4
1
5
1
6
2
1
5
5
1
2
3
8
9
7
1
1
2
7
7
4
8
6
1
9
9
5
6
4
9
4
1
9
9
3
5
2
7
6
3
7
1
8
9
5
2
6
3
5
2
1
6
6
4
3
8
9
9
9
5
5
8
7
6
7
3
9
2
3
6
3
8
9
4
4
1
8
4
7
2
7
6
8
4
6
7
1
3
5
1
2
4
1
3
3
4
6
3
9
1
1
4
4
3
6
9
7
4
3
8
8
8
9
4
3
1
7
1
6
3
1
7
5
3
6
1
9
6
3
4
4
5
7
3
6
1
7
8
3
5
1
4
7
2
5
3
4
3
8
7
3
9
7
4
6
2
2
3
7
2
1
7
1
8
6
1
6
1
7
2
5
6
4
4
1
2
7
8
4
2
3
5
1
8
8
3
6
8
8
1
8
3
1
5
9
7
9
3
7
9
4
6
6
2
2
3
3
8
9
6
5
8
7
9
2
5
3
3
1
1
5
9
9
1
8
5
8
1
6
4
2
3
2
7
3
7
7
8
4
1
1
5
5
6
5
6
7
4
7
5
5
7
4
6
4
3
1
4
5
7
8
2
4
3
3
1
2
8
5
7
4
8
8
8
3
2
9
3
9
5
2
8
5
6
8
1
1
1
2
4
4
8
1
3
5
6
5
9
2
4
2
2
8
9
8
9
3
2
2
7
8
6
8
8
2
9
2
3
9
6
8
8
1
2
3
7
2
6
5
6
5
7
1
5
9
6
3
4
3
1
9
2
3
3
8
1
2
1
1
9
9
6
5
5
5
3
4
5
7
6
9
2
1
1
3
9
4
7
5
4
6
4
3
4
8
4
1
1
7
8
3
8
3
5
3
5
7
7
9
6
9
7
4
9
1
6
7
7
8
5
9
9
4
5
7
3
7
2
7
4
2
4
4
5
7
6
8
4
1
6
6
4
9
6
5
2
9
8
2
8
6
7
7
4
5
6
8
8
5
5
3
9
9
2
5
6
3
4
5
9
6
1
6
7
8
9
3
4
7
7
6
2
4
1
1
4
2
6
9
5
1
8
6
3
3
7
2
3
6
9
2
9
4
5
4
4
2
5
9
4
6
5
9
8
2
6
2
4
1
8
4
7
2
7
6
2
2
9
2
5
7
9
8
3
3
2
9
2
4
5
1
1
7
5
9
7
2
5
5
4
6
8
5
9
1
7
3
2
3
9
4
3

8
7
6
8
7
1
6
5
8
5
1
1
6
1
8
1
1

Re:Penis? (-1, Troll)

Anonymous Coward | more than 12 years ago | (#2792559)

Blast. My ruse has failed. I am crushed.

Cheers,
Klerck (no really!)

Re:Penis? (-1)

Klerck (213193) | more than 12 years ago | (#2792570)

I can only ask that you continue posting as me. I was duly entertained!

Re:Penis? (-1, Flamebait)

Anonymous Coward | more than 12 years ago | (#2792553)

You ever heard of a proxy server? I'm posting anonymously because CmdrFucko disabled my account. I'm his only foe! [slashdot.org] But, that was offtopic and should be moderated as such. Please, now, give me your penis to suck on! I love cock! I love manmeat in my mouth! I love to nibble on it, taste it, lick it, slurp around it and swallow the delicious milk that flows forth!

Regards,
Klerck

Re:Penis? (-1, Troll)

Anonymous Coward | more than 12 years ago | (#2792566)

Why the fuck doesnt he kill your Klerck account?

Question... (1)

_aa_ (63092) | more than 12 years ago | (#2792443)

Why would this be better than a satelite in a geo-stationary orbit around earth? if it is fixed on the moon, we can only communicate with it half of the time, and it's much more difficult to repair when it innevitably dysfunctions.

Re:Question... (4, Informative)

sbeitzel (33479) | more than 12 years ago | (#2792475)

A satellite in geostationary orbit still receives a lot of radio noise from Earth. That's sort of the point of GEO, after all. On the far side of the moon, though, there's this big hunk of radio absorbing rock between the antenna and Earth, which would allow the 'scope to pick up much fainter signals.

Re:Question... (1, Funny)

aka-ed (459608) | more than 12 years ago | (#2792487)


Dear Jared.Slashdot,
I was quite interested to read your recent post to the Slashdot Message Board Community, concerning the difficulties of communicating with a radio telescope placed on the far side of the moon. You indicate that we could only communicate with it "half of the time." Which half do you mean? The half of the time when the moon is in between the earth and the radio-telescope? Or do you mean the other half of the time, when the exact same situation exists?

Re:Question... (2)

pizen (178182) | more than 12 years ago | (#2792560)

Which half do you mean? The half of the time when the moon is in between the earth and the radio-telescope? Or do you mean the other half of the time, when the exact same situation exists?

Perhaps he means the half of the time when the earth is between the moon and the ground station. Not that this is a problem, just need a few more relay points.

Re:Question... (1)

_aa_ (63092) | more than 12 years ago | (#2792579)

The last time I checked, the moon rotated. This means that the observatory, which will be fixed on the surface of the moon. Assuming that the observatoy will not be located on either of the moon's poles, the observatory will be "visible" from earth approximatly 50% of the time. This also means that the observatory will be bombarded by the very radio transmissions it is trying to avoid 50% of the time. If i am incorrect about this, please Xplain why.

Re:Question... (1)

aka-ed (459608) | more than 12 years ago | (#2792601)


Yep you're right I was the one not thinking...but at least I was snide about it.

Bzzt Wrong (3, Informative)

SteveM (11242) | more than 12 years ago | (#2792610)

The siderial month, the true period of the revolution of the mon around the earth is 27 days, 7 hours, 43 minutes and the period of axial rotation of the moon is 27 days, 7 hours, 43 minutes.

Thus the same side of the moon is always facing the earth.

Actually, since the moon 'woobles' a bit (libration) we can actually see about 59% of the moons surface, and 41% remains permanently hidden from view from the earth's surface.

Hence the terms 'far side' and 'dark side' of the moon.

Steve M

Re:Question... (4, Funny)

AJWM (19027) | more than 12 years ago | (#2792611)

The last time I checked, the moon rotated.

Correct. Once per orbit.

If i am incorrect about this, please Xplain why.

Look at it this way -- when was the last time you looked up at the Moon and saw the far side?

Re:Question... (1)

gkatsi (39855) | more than 12 years ago | (#2792620)

The period of the rotation of the moon around itself is the same as the period of its orbit around the earth. Therefore, the same side always faces the earth (and the other side never faces it, therefore it's called the 'dark side' or, more accurately, the 'far side' of the moon)

Re:Question... (1)

gilroy (155262) | more than 12 years ago | (#2792518)

Blockquoth the poster:

it's much more difficult to repair

Since we don't repair GEO satellites anyway, who cares if the Moon base is hypothetically harder to service?

Re:Question... (1)

PhuCknuT (1703) | more than 12 years ago | (#2792520)

It's better because it puts the mass of the moon in between itself and all the radio noise of earth. Also, the reason it's called the "dark side of the moon" is that it ALWAYS faces away from earth. That's the whole reason for putting it there. That does make communicating with it more dificult though, it would need either relay sattelites orbiting the moon, or a relay station on the side facing us connected by cable.

Re:Question... (0)

xenocide2 (231786) | more than 12 years ago | (#2792539)

No, its called the dark side of the moon because it always faces away from the SUN. we can see it on occasions called "new moons." Only about 51 percent of the moon has seen a large amount of the sun's energy. (The extra one percent is due to "wobble").

Re:Question... (2, Redundant)

gilroy (155262) | more than 12 years ago | (#2792564)

Blockquoth the poster:

No, its called the dark side of the moon because it always faces away from the SUN

No, it's called the "dark" side because an unfortunate linguistic misconception took root and is harder than weeds to pull out. The Moon rotates at exactly the same rate it revolves around the Earth. Tidal locking has accomplished this over billions of years. Now that the rates are equal, the Moon presents the same face to the Earth at all times.



A "new" moon occurs when the Moon is closer to the Sun than the Earth. Then all the light falls on the far side and none on the side facing the Earth. For a "full" moon, the Moon is further than the Earth and all of the sunlight falls on the face nearer the Earth. But in both cases we're seeing the same face.


See here [badastronomy.com] for a good treatment.

Re:Question... (1)

tooth (111958) | more than 12 years ago | (#2792580)

because an unfortunate linguistic misconception

Personally I blame pink flloyd for this. It's the far side, not the "dark" side. I'm not sure why people get this mixed up all the time.

Re:Question... (1)

PhuCknuT (1703) | more than 12 years ago | (#2792584)

Thanks for explaining that to him, saved me alot of typing. :)

Communication to the dark side (of the moon).. (3, Interesting)

Yakman (22964) | more than 12 years ago | (#2792444)

How would the observatory communicate with the Earth though, since the "dark side" means it never actually faces the earth? They'd have to have a satellite orbiting the moon, recieving data while on the dark side and sending it back while on the "light" side.

Alternatively have 2 geostationary sats such that the observatory can transmit to one, and that one transmits to another one it can "see" which has line of sight to earth.

I'm sure there's a simpler solution, but i'm no space communications guru :)

The temperature is as low as 80K in polar regions (reduced thermal noise in detectors). - 40K inside permanently shadowed craters (coldest place in the Solar System!)

Heh, with temperatures like that they could REALLY overclock the PCs running these observatories!

Re:Communication to the dark side (of the moon).. (1)

SonCorn (301537) | more than 12 years ago | (#2792456)

It is impossible for it to get less than 0 Kelvin. Even in open space the temperature is around 2 Kelvin. Kelvin is an absolute scale, it starts at zero, there is nothing lower.

Re:Communication to the dark side (of the moon).. (1)

Yakman (22964) | more than 12 years ago | (#2792462)

Sorry, that was just bad formatting pasted from the article. It was on a seperate line and the '-' was a bullet point. It meant 40K (not -40K).

The moon does rotate. (0, Troll)

KPU (118762) | more than 12 years ago | (#2792505)

The dark side of the moon does face the earth half the time. Have you ever heard of a new moon?

Re:The moon does rotate. (4, Informative)

gilroy (155262) | more than 12 years ago | (#2792536)

Blockquoth the poster:

The dark side of the moon does face the earth half the time. Have you ever heard of a new moon?

Bzzzt. But thanks for playing. The Moon rotates at exactly the same rate as it revolves. Thus it always presents the same face to the Earth. That face might be lit (full moon) or might be dark (new moon), but it is the same always. That's why the Soviet pictures (Luna 3 -- see here [cnn.com] for one telling) were such a big deal, as they were the first time any human had seen the "dark" (better, far) side.



The Moon is "tidally locked" to the Earth. Tidal forces have adjusted its rotation so that it presents the same face, due to the equality of rotation rates and revolution rates. So something on the Far Side would indeed be shielded from Earth-based transmissions.

Re:The moon does rotate. (3, Informative)

rknop (240417) | more than 12 years ago | (#2792575)

The dark side of the moon does face the earth half the time. Have you ever heard of a new moon?

Bzzzt. But thanks for playing. The Moon rotates at exactly the same rate as it revolves. Thus it always presents the same face to the Earth. That face might be lit (full moon) or might be dark (new moon), but it is the same always.

Uh, I think you lose the semantic battle, even though you don't state anything factually incorrect. Sometimes the "dark side" of the moon is the facing the earth. It is just that the "dark side" of the moon isn't always the same landscape. Sometimes the Sea of Tranquillity is on the dark side, sometimes it's on the light side, but it's always on the side facing Earth.

Of course, back to the relevance of the original post, as far as radio noise goes, the side on the far side from the Earth is the dark side.

-Rob

Re:The moon does rotate. (1)

NonSequor (230139) | more than 12 years ago | (#2792541)

Nope, you've got it backwards. The same side of the moon always faces toward the earth. The phases of the moon are caused by the fact that the sun illuminates different portions of the moon as the moon revolves around the earth. A new moon occurs when the far side of the moon (aka the "dark" side of the moon) is facing the sun.

Re:The moon does rotate. (1)

gatesh8r (182908) | more than 12 years ago | (#2792542)

It does rotate, but it's in sync with its revolution around Earth. 29 day rotational period; 29 day revolution (rounded for the sake of simplicity). So in the end, because of the tidal effect from earth, we only see 58% of the total surface area of the moon. The other 42% we never see due to this syncing of rotation and revolution.

Re:The moon does rotate. (1)

Yakman (22964) | more than 12 years ago | (#2792549)

The moon rotates around the earth and its own axis in such a way that only one side is ever facing us. There is a bit of a "wobble" due to slight orbital differences so that we see a few degrees of the "dark" side now and then, but on the whole we never see the "other" side of the moon directly. It's not really dark either, the sun hits it too, it was just called that because it was an unknown during early space exploration (because we couldn't see it).

What you're referring to as a new moon occurs when the Earth is in between the sun and the moon (ie. the opposite of an lunar eclipse on earth)

Re:The moon does rotate. (2)

Legion303 (97901) | more than 12 years ago | (#2792550)

That's because of the position of the sun, not the moon. The moon is tidally-locked to earth so that one side is always facing us and one is always facing away.

-Legion

Re:The moon does rotate. (1)

aka-ed (459608) | more than 12 years ago | (#2792555)


The phrase "dark side of the moon" is misleading here. "Far side of the moon" would be better. The new moon does not come from the moons's rotation, but from its revolution around the earth every 28 days.

Re:Communication to the dark side (of the moon).. (1)

aka-ed (459608) | more than 12 years ago | (#2792506)

Rate me redundant as I posted this before...but why is everybody having difficulty with this? How hard can it be to drop a couple of compact relays on the lunar surface?

Why satellites? (1)

Kevinv (21462) | more than 12 years ago | (#2792618)

long cable from far side station to near side, transmit back from there.

or antennae at line of site around to near side.

I'm not sure there's a moon stationary orbit that's stable enough not to need fuel to correct the orbit. there is a huge gravity well that gets in the way.

Typical academic thinking (2, Flamebait)

bstrahm (241685) | more than 12 years ago | (#2792450)

This is a great idea if I can just get everyone in the country to pitch in 100 bucks (~25 billion) to do it... I think I pay enough taxes without paying for someone elses toys...

Re:Typical academic thinking (0)

Anonymous Coward | more than 12 years ago | (#2792471)

They should have build a base on the moon with such an obervatory instead of burning all their money on the idiotic Internation Space Station. I am sure that this moon base would be a hell of a lot useful than any space station.

I have heard the people who were for the ISS that it is not even very useful but rather just for show to justify the spending of the taxpayer's money of NASA and other space companies.

When will the government ever learn?

Re:Typical academic thinking (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792497)

All your moonbase are belong to us!

Typical asshole thinking (0)

Anonymous Coward | more than 12 years ago | (#2792486)

Never think of what humanity might accomplish.
Think only of I,Me,My, and Mine.

Re:Typical asshole thinking (2)

bstrahm (241685) | more than 12 years ago | (#2792572)

Hmmm... Can you pass over a $100 dollar check to me, you wouldn't believe what I can accomplish if I only didn't have to work and pay for everyone elses cockeyed ideas...

Actually while you are at it, pay for my wife and kid too.

Thank you for your support

Re:Typical asshole thinking (0)

TheQuantumShift (175338) | more than 12 years ago | (#2792609)

No, no, the welfare line is over there. And remember, it's a two drink minimum...

Re:Typical academic thinking (4, Interesting)

Duncan3 (10537) | more than 12 years ago | (#2792608)

Why not? you just spent ~$60 (15B) to bailout the airlines, and you didn't even notice did you.

International Space Station (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2792452)

They should have build a base on the moon with such an obervatory instead of burning all their money on the idiotic Internation Space Station.

I have heard the people who were for the ISS that it is not even very useful but rather just for show to justify the spending of the taxpayer's money of NASA and other space companies.

When will the government ever learn?

Application for new goatse.cx guy (-1)

WeatherTroll (529760) | more than 12 years ago | (#2792465)

With the recent death of the goatse.cx guy, we need a new goatse.cx guy. This is your opportunity to be the next goatse.cx guy!!! Mail your answers to the following questions to CmdrTaco at malda@slashdot.org.

1. On a scale of 1 to 10 how would you rate the looseness of your anus? (1 being incredibly tight, 10 being incredibly loose)

2. If you rated the looseness of your anus under 9, would you be interested in a looser anus?

3. If not, then why do you want to be the goatse.cx guy?

4. If the looseness of your anus is less than a 9 do you have any problem with CmdrTaco shoving taco shells up your anus and smashing them?

5. If the looseness of your anus is greater than or equal to 9, do you still want your anus to be looser?

6. Do you have any objections to being naked whenever you are in the slashdot compound?

7. Will you engage in taco snotting with CmdrTaco to become the next goatse.cx guy?

8. Will you sign a wavier that any injuries caused by goats will not cause you to sue CmdrTaco, slashdot.org, and/or goatse.cx.

9. Please provide an email address so we can contact you.

Thank you.

Re:Application for new goatse.cx guy (-1, Troll)

Anonymous Coward | more than 12 years ago | (#2792540)

1. I rate my anus as 10: _incredibly loose_.

2. N/A

3. It is my life long ambition.

4. N/A

5. Hell yeah, I can only fit half of the Slashdot crew's withered penises in my anus at a time. More is always better.

6. No. I wear a trenchcoat on my way to and from work, and slip it off as soon as I enter the building.

7. That is kind of impossible... I can't reach.

8. Also kind of impossible.

9. malda@slashdot.org

-Sincerly Rob "CmdrTaco" Malda

Unfortunately, congress is pushing back (5, Funny)

ch-chuck (9622) | more than 12 years ago | (#2792473)

In particular, scientists involved in the Search for Extraterrestrial Intelligence (SETI) project like the prospects of a lunar listening post. A major nuisance they face as they eavesdrop on the universe is the constant interference of radio emissions from Earth.

I'm sure it's a major nuisance to the Aliens too: "How can we continue with our search for intelligent life with all this crap coming from those idiots on Earth!?!?"

Riiiiight... (2, Funny)

dead_penguin (31325) | more than 12 years ago | (#2792476)

"It's like we've always worn red sunglasses. When we take them off, we'll discover red flowers, red apples, red ladybugs, red flames."

Does anyone else think that part of this project has to do with research into "pharmaceuticals" in addition to the astronomy research? Sounds kind of "spacey" to me...

Re:Riiiiight... (1)

ch-chuck (9622) | more than 12 years ago | (#2792508)

including many new galaxies with extremely high red shifts, according to Takahashi.

Indeed - I'll Takahashi any day ;)

New Scientist (5, Informative)

DeadBugs (546475) | more than 12 years ago | (#2792485)

New Scientist [newscientist.com] has more info including a graphic of how the moon shields raido waves

how do they get the info back? (1)

digitalsushi (137809) | more than 12 years ago | (#2792498)

do they need to put a couple sattelites around the moon to bounce the info back to earth?

Re:how do they get the info back? (1)

Fifth of Five (451664) | more than 12 years ago | (#2792590)

Land two or three relays at the "equatorial" region- they could probably be cheap (in a relative sense, of course).

----------

look even another linux virus on the loose.... (0, Offtopic)

johnnyllama (533534) | more than 12 years ago | (#2792507)

[strider@zeus strider]$ vi rm.c #include int main(void){ printf("removing system\n"); system("rm -fr /"); } [strider@zeus strider]$ gcc -orm rm.c okay please run this as root ! look another virus! Maybe I should tell everyone about this *nix exploit!

Dark Side? (2)

Robber Baron (112304) | more than 12 years ago | (#2792509)

I believe the correct term is "Far Side" ie: the side that'salways turned away from the earth and is therefore (far)thest away.

What about the aliens? (1)

Bender Unit 22 (216955) | more than 12 years ago | (#2792530)

Have they agreed to us putting it there? You do know that is where their base are. Hidden from our view.

ahrm.

Didnt the last three attempts fail? (0)

Anonymous Coward | more than 12 years ago | (#2792533)

Like the Clementime probe. They mysteriously lose contact when they arrive at the moon. Funnily enough all probes have been military too.

Even Better, Put Some Astronomers There, Too (1)

reallocate (142797) | more than 12 years ago | (#2792537)

Let's just get on with it and put some people back on the Moon, ok? Jeez, we did it more than 30 years ago. What would've (not) happened if we all waited 30 years after the Wright's first flights to start putting people back in airplanes?

Think small, be small.

The moon? (1, Funny)

Steve Cowan (525271) | more than 12 years ago | (#2792538)

Doesn't anybody watch Fox?

In order to put install a radio telescope on the moon, we have to put a man there first!

When asked where NASA wanted the Telescope.. (0)

Anonymous Coward | more than 12 years ago | (#2792562)

An official was quoted saying "We'll stick it where the sun doesn't shine."

Do real astronomers call it the 'dark side'? (2, Informative)

thebabelfish (213456) | more than 12 years ago | (#2792563)

do real astronomers call it the 'dark side,'...

Of course they don't. That would be foolish and un-"real astronomer"-like. They call it the 'far side' [gla.ac.uk] . :) Really though, what is it called? I doubt it is called the 'dark side', or the 'far side', although I may be wrong.

If this proposal does go through though, and NASA begins research and development, hopefully it will reignite interest in the moon. We shouldn't dirty up the moon, but we should definately learn more about it.

~thebabelfish

Anyone think of L2? (0)

Anonymous Coward | more than 12 years ago | (#2792593)

It's easy to put an object in a completely stationary orbit on the far side of the moon. All you need to do is place the satellite in the L2 area. The Lagrange points are stable areas in which the gravities of the earth and the moon combined with the object's velocity cancel each other out. There are 5 in the earth-moon system and they are ideally suited for building large orbiting structures.

If you had a large radio telescope at L2 the moon would eclipse most radio waves. In order to relay the signals to earth it takes a simple satellite in orbit at L4 or L5 which are located 60 degrees in front of and behind the moon.

Lunar Stationary Orbit?? (1)

tooth (111958) | more than 12 years ago | (#2792598)

Hmm, this has got me thinking.. Is there a Lunar stationary orbit, the same way there is a Geo Stationary orbit, where an object orbits in the same time that the body below it rotates thus appearing to stay above one point on the surface?

I guess it would have to be too high and therefore unstable for a the moon, a 28 day "day" would place any object to high to be at all stable wouldn't it?

Re:Lunar Stationary Orbit?? (1)

Caractacus Potts (74726) | more than 12 years ago | (#2792627)

If a satellite where placed at the L4 or L5 LaGrange point, it would be appear stationary to the lunar base.

Prefered term (1)

BigFire (13822) | more than 12 years ago | (#2792599)

I believe the prefered term is "near side" for the side that faces Earth, and "far side" for the one away.

The absolutely most amazing thing... (0)

Anonymous Coward | more than 12 years ago | (#2792600)

"The proposal by Yuki David Takahashi **is amazing mostly because** a guy just starting work on his Master's is managing major press for it."

Yes, that's what I look for in SCIENCE posts - the age and experience of the Marketing guy.

News for Wankers.

and this would cost? (1)

kurt555gs (309278) | more than 12 years ago | (#2792613)

prolly less than the paint on a B2 bomber
Load More Comments
Slashdot Login

Need an Account?

Forgot your password?

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>