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Rincewind
10-09-2013, 05:23 PM
Stop start animation of the eclipse/transit of Phobos as seen from surface of Mars by NASA rover Curiosity.

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Capablanca-Fan
12-09-2013, 05:50 AM
Nice pics. Mars doesn't have a moon anywhere as big as ours, which is only 400 times smaller in diameter, as well as 400 times closer, enabling total eclipses. See also The sun: our special star (http://creation.com/the-sun-our-special-star).

Ian Murray
13-09-2013, 04:24 PM
Nice pics. Mars doesn't have a moon anywhere as big as ours, which is only 400 times smaller in diameter, as well as 400 times closer, enabling total eclipses.
Then again Mars is an average of 38 million km further away from the sun, so the sun appears as a correspondingly smaller sphere (~45% of its size viewed from earth). If Phobos was a bit closer to the Arian surface a total eclipse would be possible, albeit shorter-lived.

Capablanca-Fan
14-09-2013, 06:11 AM
Then again Mars is an average of 38 million km further away from the sun, so the sun appears as a correspondingly smaller sphere (~45% of its size viewed from earth). If Phobos was a bit closer to the Arian surface a total eclipse would be possible, albeit shorter-lived.
Would probably need to be almost three times closer, just from eyeballing RW's movie. This would be well inside the Roche Limit (http://burro.astr.cwru.edu/stu/advanced/mars_moons.html), so Phobos would shatter under Mars' tital forces.

Ian Murray
14-09-2013, 09:00 AM
Would probably need to be almost three times closer, just from eyeballing RW's movie. This would be well inside the Roche Limit (http://burro.astr.cwru.edu/stu/advanced/mars_moons.html), so Phobos would shatter under Mars' tital forces.
Twice as close would do it, according to David Dickinson (http://www.universetoday.com/104404/curiosity-spies-a-martian-annular-eclipse/), which would be touch and go - estimated Roche limit of 5000 km vs ~4610 km orbital altitude at perigee.

Astronomers (and Martian settlers) will be able to see for themselves which way it goes when Phobos' orbit continues its decay to reach that altitude. A bit later on those left on earth will be able to watch the last total eclipse by the moon before it spirals out of total-eclipse range.

Desmond
14-09-2013, 10:03 AM
Twice as close would do it, according to David Dickinson (http://www.universetoday.com/104404/curiosity-spies-a-martian-annular-eclipse/), which would be touch and go - estimated Roche limit of 5000 km vs ~4610 km orbital altitude at perigee.

Astronomers (and Martian settlers) will be able to see for themselves which way it goes when Phobos' orbit continues its decay to reach that altitude. A bit later on those left on earth will be able to watch the last total eclipse by the moon before it spirals out of total-eclipse range.
Are Mars' moons altitudes decreasing? That's interesting as (unless I am mistaken) the Earth's Moon is going the other way.

Rincewind
14-09-2013, 11:10 AM
Twice as close would do it, according to David Dickinson (http://www.universetoday.com/104404/curiosity-spies-a-martian-annular-eclipse/), which would be touch and go - estimated Roche limit of 5000 km vs ~4610 km orbital altitude at perigee.

It doesn't even need to be that dramatic for some total eclipses. Mars has quite an eccentric orbit compared to Earth and so at the maximum distance from the sun (aphelion ~250E6 km) the subtend angle on the surface of Mars at noon is around 2.8E-3 radians. This will be the time in the Martian year when the sun appears the smallest in the sky. Now Phobos has a radius of 11km and so to subtend that angle it would need to be around 3900 km above the Martian surface which equate to an orbital radius of around 7300km. As already pointed out this can be the periapsis distance and Phobos can be further away for most of its orbit. It is also well outside the Roche limit.

Of course such eclipses would be rare and the annular variety would be the norm but totality would occur occasionally.


Astronomers (and Martian settlers) will be able to see for themselves which way it goes when Phobos' orbit continues its decay to reach that altitude. A bit later on those left on earth will be able to watch the last total eclipse by the moon before it spirals out of total-eclipse range.

Certain eclipses here are not total now. Depending on where the moon is in its orbit and where on the earth's surface the shadow falls we get annular eclipses of the moon where the moon is directly over the sun but does not block it out completely. For example the one visible in the Northern Territory earlier this year was annular.

2334

Rincewind
14-09-2013, 11:24 AM
Are Mars' moons altitudes decreasing? That's interesting as (unless I am mistaken) the Earth's Moon is going the other way.

Yes that is correct. Dissipative effects lead to a decay of orbits which in general leads to a decrease in altitude. So Mars-Phobos is "normal". The moon is getting further away from earth which is an increase in potential energy and is driven by tidal forces. Where is the energy coming from for this increase in orbit? Believe it or not is the slowing down of Earth rotation on axis. This is a well understood phenomenon called tidal locking (in fact it is just a special case of conservation of total angular momentum of the earth/moon system). The orbit and rotation of the moon are locked already which is why we always see the same face of the moon. Eventually the earth's rotation will lock to the rotation of the moon too. When that happens you will only be able to see the moon from half of the planet. It will be never visible from the other half but that will take a loooong time.

Rincewind
14-09-2013, 11:48 AM
Post script.

Once the earth has locked to the orbit of the moon, I expect that dissipative forces will take over and the moon's orbit will begin to decay, causing it to eventually come back into total eclipse range.

Capablanca-Fan
14-09-2013, 12:45 PM
Are Mars' moons altitudes decreasing? That's interesting as (unless I am mistaken) the Earth's Moon is going the other way.
Indeed it is; see The moon’s recession and age (http://creation.com/the-moons-recession-and-age).

Capablanca-Fan
14-09-2013, 12:55 PM
Certain eclipses here are not total now. Depending on where the moon is in its orbit and where on the earth's surface the shadow falls we get annular eclipses of the moon where the moon is directly over the sun but does not block it out completely. For example the one visible in the Northern Territory earlier this year was annular.

2334
Not as spectacular as the total variety, but I was fortunate enough to see an annular eclipse in Wellington about 20 years ago. Even though most of the sun's surface is blocked, it was still important to use proper filters to view it, because even the visible part of the photosphere emits light bright enough to damage the retina.

Rincewind
14-09-2013, 02:30 PM
Indeed it is; see The moon’s recession and age (http://creation.com/the-moons-recession-and-age).

Jono's regurgitation of DeYoung's failed argument, while amusing is not science.

For a good debunking of this simplistic argument is here: http://podcast.sjrdesign.net/media/podcasts/PseudoAstro_045.mp3

Capablanca-Fan
14-09-2013, 02:35 PM
Who cares about silly audio files?

Rincewind
14-09-2013, 03:10 PM
Who cares about silly audio files?

More than sensible enough to debunk your silly pseudo-scientific claims.

Ian Murray
14-09-2013, 03:37 PM
More than sensible enough to debunk your silly pseudo-scientific claims.

Evidence supports the 4.6 Gya theory - we have rock samples from the moon which have been dated (http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/clkroc.html#c9).

Desmond
14-09-2013, 04:39 PM
Indeed it is; see The moon’s recession and age (http://creation.com/the-moons-recession-and-age).

I quite like this explanation.

inES_eAexN8

Rincewind
14-09-2013, 06:07 PM
I quite like this explanation.

Yes amusing but does not address DeYoung's argument as cut and pasted by Jono. Jono's point is that 50 years ago (yes that's right, he quotes Baldwin (1965) as a misrepresentation of current scientific thinking) there was some disagreement on the time scales issue. Yes the arrangement of the continents is an issue but the other issue is that the rough calculation used by DeYoung does not accurately capture all important physics of the problem and that is why a simplistic calculation does not yield a date commensurate with other evidence such as moon rock dating. Current accurate models have no problem with the moon being an age of 4.6 billion years. Which makes Jono's claim that "this issue has been a long-standing challenge to conventional chronology," nothing more than a boldfaced lie. Is is not a current challenge at all as it was adequately explained by non-toy models at least 30 years ago (See Webb Geophysical Journal International (1982)).

antichrist
14-09-2013, 08:51 PM
Not as spectacular as the total variety, but I was fortunate enough to see an annular eclipse in Wellington about 20 years ago. Even though most of the sun's surface is blocked, it was still important to use proper filters to view it, because even the visible part of the photosphere emits light bright enough to damage the retina.

can I be a little off topic. I find it grossly irresponsible how TV news often show that arc welding whatever it is that damages the eyes and creates nightmares I am led to believe, the workers doing the job has special shields, but watching it on TV gives the appearance that it is all right to watch without special eye protection. Actually the same goes for when TV shows those eclipses that are also damaging to the eye, maybe they give warnings then but not for the welding. Oh yeah, that welding makes a good bright foto but..........

Capablanca-Fan
15-09-2013, 01:32 AM
Evidence supports the 4.6 Gya theory - we have rock samples from the moon which have been dated (http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/clkroc.html#c9).
Radiometric dating has numerous flaws. See The way it really is: little-known facts about radiometric dating: Long-age geologists will not accept a radiometric date unless it matches their pre-existing expectations (http://creation.com/the-way-it-really-is-little-known-facts-about-radiometric-dating).

Capablanca-Fan
15-09-2013, 01:34 AM
Yes amusing but does not address DeYoung's argument as cut and pasted by Jono. Jono's point is that 50 years ago (yes that's right, he quotes Baldwin (1965) as a misrepresentation of current scientific thinking) there was some disagreement on the time scales issue. Yes the arrangement of the continents is an issue but the other issue is that the rough calculation used by DeYoung does not accurately capture all important physics of the problem and that is why a simplistic calculation does not yield a date commensurate with other evidence such as moon rock dating. Current accurate models have no problem with the moon being an age of 4.6 billion years. Which makes Jono's claim that "this issue has been a long-standing challenge to conventional chronology," nothing more than a boldfaced lie. Is is not a current challenge at all as it was adequately explained by non-toy models at least 30 years ago (See Webb Geophysical Journal International (1982)).
More crap. My article (http://creation.com/the-moon-the-light-that-rules-the-night) then Dr Henry's paper (http://creation.com/the-moons-recession-and-age) (the one RW quotes from but attributes to me) addresses the more recent wriggles. Astronomy professor Dr Danny Faulkner has also provided reasons to reject the excuses.

Capablanca-Fan
15-09-2013, 01:43 AM
can I be a little off topic. I find it grossly irresponsible how TV news often show that arc welding whatever it is that damages the eyes and creates nightmares I am led to believe, the workers doing the job has special shields, but watching it on TV gives the appearance that it is all right to watch without special eye protection. Actually the same goes for when TV shows those eclipses that are also damaging to the eye, maybe they give warnings then but not for the welding. Oh yeah, that welding makes a good bright foto but..........
I'm not sure what alternative you would propose. I thought it would be clear from the eye protection that directly looking at the welding could cause eye damage. Of course, the damaging invisible UV and IR won't be emitted by the TV screen. Here is a NASA page on eye protection during solar eclipses (http://eclipse.gsfc.nasa.gov/SEhelp/safety.html). Improper filters are dangerous; the sun seems dimmer, and the retina has no pain nerves, so you don't realise the damage being caused.

Rincewind
15-09-2013, 01:55 AM
(the one RW quotes from but attributes to me)

I attribute the cut and paste of DeYoung's argument to you. By posting the link here you are promulgating the lie and therefore a liar by action. Unless you recant the issues that I raise (that is that science has any problem reconciling the age of the moon with the altitude of the moon's orbit). It doesn't and to claim it does is simply demonstrably wrong since Baldwin's concerns were addressed in the 1980s.


Astronomy professor

(retired) and now young earth creationist


Dr Danny Faulkner has also provided reasons to reject the excuses.

Which are in no way compromised by his religious convictions... NOT.

Rincewind
15-09-2013, 02:00 AM
Radiometric dating has numerous flaws.

More bullshit. Radiometric dating is not flawed at all. It has certain limitations but any attempt to demonstrate it is not reliable when used properly have fallen flat as previous discussion in this board demonstrated.

rr would like the following explanation...

loPHYsLHb5Q

antichrist
15-09-2013, 09:22 AM
I'm not sure what alternative you would propose. I thought it would be clear from the eye protection that directly looking at the welding could cause eye damage. Of course, the damaging invisible UV and IR won't be emitted by the TV screen. Here is a NASA page on eye protection during solar eclipses (http://eclipse.gsfc.nasa.gov/SEhelp/safety.html). Improper filters are dangerous; the sun seems dimmer, and the retina has no pain nerves, so you don't realise the damage being caused.

but would children know that it is necessary when they are shown the naked flame on TV every second night, for special effects it seems. It is not so common now but occasionally the welding is still done in the open without screens to protect passers by. End of off topic

Ian Murray
15-09-2013, 07:51 PM
...Long-age geologists will not accept a radiometric date unless it matches their pre-existing expectations.
That's rich. Creationists will not accept anything which contradicts their interpretation of the bible, while the goal of science is to learn the truth, not to disprove biblical interpretation. You were a scientist yourself once - you should know that.

Tas Walker spends the whole page making assumptions about the assumptions an imaginary geologist might make. Smoke and mirrors.

Rincewind
15-09-2013, 10:07 PM
That's rich. Creationists will not accept anything which contradicts their interpretation of the bible, while the goal of science is to learn the truth, not to disprove biblical interpretation. You were a scientist yourself once - you should know that.

The report from the Young Earth Creationist's who tried to disprove radioactive dating methods is an eye opener. Ostensibly they were looking at the evidence of radio dating methods and come to some conclusion. However of course they already had an a priori belief that the universe was < 10kYr so they were just looking from straws that they might grasp so it was not research at all, it was apologetics.

Anyway the prologue of their book describes the method and format of meetinges, etc. It proceeds as follows...


Right from the start each scientist declared his complete faith in Scripture.

John Morris, Prologue, Page vi, Radioisotopes and the Age of the Earth (A Young-Earth Creationist Research Initiative)

So they were not being scientific in any way at all. Looking at the data and drawing conclusions from that alone. No they were looking at everything through the distorting lens of creation stories of bronze age shepherds. If the data didn't fit their faith then it was the data that had to be wrong.

And they wonder why people laugh at creationists.

Capablanca-Fan
17-09-2013, 02:40 AM
That's rich. Creationists will not accept anything which contradicts their interpretation of the bible,
It is the objective historical grammatical (http://creation.com/should-genesis-be-taken-literally) interpretation held by the church for 1,800 years (http://creation.com/old-earth-or-young-earth-belief) when they believed the text rather than tried to appease uniformitarian dogma.


while the goal of science is to learn the truth, not to disprove biblical interpretation.
Indeed it is. But as misused by the likes of Dawkins, they are after only materialistic explanations, not correct explanations.


You were a scientist yourself once — you should know that.
I still am a scientist, while you never were.


Tas Walker spends the whole page making assumptions about the assumptions an imaginary geologist might make. Smoke and mirrors.
He knows full well, because his honours project in geology, for which he received 1st class, was about dating methods. One important discovery was nice stright "isochron" plots. The only problem is that they were made with stable i

Rincewind
17-09-2013, 12:58 PM
It is the objective historical grammatical (http://creation.com/should-genesis-be-taken-literally) interpretation held by the church for 1,800 years (http://creation.com/old-earth-or-young-earth-belief) when they believed the text rather than tried to appease uniformitarian dogma.

Yes but it is not science it is apologetics. Science is about generating new knowledge not believing that scientific truth was revealed by a divine agent to bronze age shepherds several millennia ago.


Indeed it is. But as misused by the likes of Dawkins, they are after only materialistic explanations, not correct explanations.

"The magic man in the sky did it" is not an explanation.


I still am a scientist, while you never were.

No you did a HDR degree which qualified you to work as a scientist. However since graduation you have produced practically zero scientific output.


He knows full well, because his honours project in geology, for which he received 1st class, was about dating methods. One important discovery was nice stright "isochron" plots. The only problem is that they were made with stable i

You should know that an honours year project is not considered a higher degree research program. It is basically a program which is mostly course work where students are prepared for research by taking some graduate level courses and the project gives them an introduction to research. While some honours projects are interesting and leads to scientific output, most do not. If Tas's research really did discover something that was hitherto unknown and important it should have been published. Do you have a reference to a paper?

Ian Murray
17-09-2013, 06:24 PM
Indeed it is. But as misused by the likes of Dawkins, they are after only materialistic explanations, not correct explanations.
That's your twisted view of science, that scientists are all venal and in worldwide collusion for personal gain to distort truth, as you define it in the 'light' of ancient scripture. The idea of scientists all being in it for the money is clearly irrational, not supported by reality.


I still am a scientist, while you never were.
I've never claimed to be, but I am fascinated by the scientific search for truth, e.g. only a decade ago they discovered that ~95% of the universe is made up of dark matter and dark energy. They know they are there, but freely admit that they don't know what they are. Not yet - they're working on it. That's real science.


He knows full well, because his honours project in geology, for which he received 1st class, was about dating methods. One important discovery was nice stright "isochron" plots. The only problem is that they were made with stable i
The whole paper is pure speculation and unsupported allegations, propped up with speculative geostrata diagrams. His footnote references lead nowhere. If he submitted that as a high school science assignment he would be failed.

Capablanca-Fan
18-09-2013, 04:59 AM
That's your twisted view of science, that scientists are all venal and in worldwide collusion for personal gain to distort truth, as you define it in the 'light' of ancient scripture. The idea of scientists all being in it for the money is clearly irrational, not supported by reality.
Who said anything about money? Sounds like you are the one having problems with reality.


I've never claimed to be, but I am fascinated by the scientific search for truth, e.g. only a decade ago they discovered that ~95% of the universe is made up of dark matter and dark energy. They know they are there, but freely admit that they don't know what they are. Not yet - they're working on it. That's real science.
Yet Dr John Hartnett, a biblical creationist and tenured professor of physics at the University of Western Australia, has come up with a genuine physical explanation for the phenomena explained by the fudge factor of dark matter. See Has ‘dark matter’ really been proven? (http://creation.com/has-dark-matter-really-been-proven) that might almost be simple enough even for you to understand, and his bio (http://creation.com/dr-john-hartnett-cv) for his papers published in secular journals on t


The whole paper is pure speculation and unsupported allegations, propped up with speculative geostrata diagrams. His footnote references lead nowhere. If he submitted that as a high school science assignment he would be failed.
Maybe at a school you taught at, because of your leftatheopathic ideology, but his paper earned First Class Honours.

Rincewind
18-09-2013, 10:59 AM
Yet Dr John Hartnett, a biblical creationist and tenured professor of physics at the University of Western Australia, has come up with a genuine physical explanation for the phenomena explained by the fudge factor of dark matter.

That claim has already been thoroughly debunked. Hartnett't theory is grounded in the fringe physics of Carmelian cosmological relativity and furthermore Harnett's alternative explanation contains a huge fudge factor which he has no way to determine and he blatantly just plucks values out of the air.

Ian Murray
18-09-2013, 05:29 PM
That claim has already been thoroughly debunked. Hartnett't theory is grounded in the fringe physics of Carmelian cosmological relativity and furthermore Harnett's alternative explanation contains a huge fudge factor which he has no way to determine and he blatantly just plucks values out of the air.

Reception of his work on the subject has been underwhelming. His seminal work Hartnett, John G. "The distance modulus determined from Carmeli’s cosmology fits the accelerating universe data of the high-redshift type Ia supernovae without dark matter." Foundations of Physics 36.6 (2006): 839-861. has been cited 11 times outside creation circles, according to Google Scholar. Nine of those were by Hartnett himself in other works, one in an appendix to a Carmeli book and one passing mention in Smith and Oztas 2008:

...A Ωm of either 0.22 or 0.18 are both within the important range as currently thought by many, for while many astronomers believe Ωm is presently about 0.25, some people [i.e. Hartnett and Oleivera] think values much lower, current Ωm down to about 0.05 are more reasonable

Ian Murray
18-09-2013, 08:57 PM
Who said anything about money?
You. Many times you've alleged that scientists collude to obtain grant funds with distorted grant applications


Yet Dr John Hartnett, a biblical creationist and tenured professor of physics at the University of Western Australia...
He's out on a limb with negligible support. If you want to catch up on current theory, have a look at a few of the lectures from the course I'm doing, conducted by Hitoshi Murayama, Professor of Physics at UC Berkeley:
https://www.dropbox.com/s/7r306v9kbu2okce/4%20-%202%20-%203-2%20Dark%20Matter%20I%20%280624%29.mp4
https://www.dropbox.com/s/peudg5xjx9gh1zd/4%20-%203%20-%203-3%20Dark%20Matter%20II%20%281020%29.mp4
https://www.dropbox.com/s/sazezobza1n8yr9/4%20-%204%20-%203-4%20Nature%20of%20Dark%20Matter%20I%20%280938%29.m p4
https://www.dropbox.com/s/eknng9ugzpmm8bm/4%20-%205%20-%203-5%20Nature%20of%20Dark%20Matter%20II%20%280929%29. mp4


Maybe at a school you taught at, because of your leftatheopathic ideology, but his paper earned First Class Honours.
Flattery will get you nowhere. I'm not an ex-teacher, just a gifted amateur.:D
Walker's uni work might have got him honours, but his CMI stuff is crap.

Ian Murray
20-09-2013, 09:35 AM
https://www.dropbox.com/Dark Matter 1
https://www.dropbox.com/Dark Matter 2
https://www.dropbox.com/Nature of Dark Matter 1
https://www.dropbox.com/Nature of Dark Matter 2

Temporary files now deleted. Check https://www.youtube.com/watch?v=TGHqg9HuxkE&feature=player_embedded and http://www.ipmu.jp/hitoshi-murayama

Capablanca-Fan
26-09-2013, 07:36 AM
He's out on a limb with negligible support. If you want to catch up on current theory, have a look at a few of the lectures from the course I'm doing, conducted by Hitoshi Murayama, Professor of Physics at UC Berkeley:
How nice, so someone of equal rank to Dr Hartnett; hope he can manage dumb it down enough for you.


Flattery will get you nowhere. I'm not an ex-teacher, just a gifted amateur.:D
An amateur at any rate.


Walker's uni work might have got him honours, but his CMI stuff is crap.
As if you would know.

Capablanca-Fan
26-09-2013, 07:44 AM
Reception of his work on the subject has been underwhelming. His seminal work Hartnett, John G. "The distance modulus determined from Carmeli’s cosmology fits the accelerating universe data of the high-redshift type Ia supernovae without dark matter."
This paper shows that Carmelian relativity solves problems without resorting to dark matter.

Rincewind
26-09-2013, 10:50 AM
This paper shows that Carmelian relativity solves problems without resorting to dark matter.

The elephant in the room is that nobody in the scientific world thinks Carmelian relativity is real physics.

Edit: I found there was a Wiki page of Cosmological relativity but it was deleted because it is junk science. The talk page (http://en.wikipedia.org/wiki/Wikipedia%3AArticles_for_deletion%2FCarmeli%27s_co smological_relativity) explains why.