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#776 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
Posts: 7,773
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Martian methane mystery deepens
Interesting article on the BBC site about the Martian methane mystery.
What do you think? Life or geology? |
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#777 |
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Join Date: Nov 2004
Location: Solihull
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Quote:
Interesting article on the BBC site about the Martian methane mystery.
What do you think? Life or geology? |
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#778 |
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Join Date: Nov 2001
Location: SE London.
Posts: 781
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Earth's rotation.
The earth rotates from West to East. If every vehicle on earth were positioned facing due East & all simultaniously accelerated from a standstill at full throttle would the combined inertia have a measurable affect on the earth's rotation?
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#779 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
Posts: 7,773
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Quote:
The earth rotates from West to East. If every vehicle on earth were positioned facing due East & all simultaniously accelerated from a standstill at full throttle would the combined inertia have a measurable affect on the earth's rotation?
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#780 |
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Join Date: May 2004
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Quote:
Interesting article on the BBC site about the Martian methane mystery.
What do you think? Life or geology? It really is too soon to tell and those future robot expeditions will hopefully answer the questions. However, I think it might be possible to hazard a guess. So far, from either orbiters or landers, there's been no conclusive evidence of any active life forms. However, there's plenty of evidence of volcanic and other geological activity including within the past few million years or so (very recent in geological terms). My betting is that the methane emissions are geological in origin and as Mars has no substantive magnetic field or ozone layer, a combination of full blast solar radiation impinging directly on the atmosphere and atmospheric chemistry might explain the enhanced methane destruction rate that's been reported. PS I guess Martian purists would insist that I should use 'areological' instead of 'geological' but I think it's the understanding that counts.
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#781 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
Posts: 7,773
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Here's a video of a shuttle crew practicing an emergency launchpad exit. I can't help thinking though that if anything occured that called for one, they'd not stand a chance anyway!
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#782 |
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Join Date: Jun 2006
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Quote:
Here's a video of a shuttle crew practicing an emergency launchpad exit. I can't help thinking though that if anything occured that called for one, they'd not stand a chance anyway!
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#783 |
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Inactive Member
Join Date: Oct 2005
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Quote:
I have always thought that about the escape system they devised after Challenger.
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#784 |
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Join Date: Jun 2006
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Quote:
The bail out pole thing?
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#785 |
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Forum Member
Join Date: May 2002
Location: Bishop-Auckland / Darlington
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Perseids.
Anyone who is interested - don't forget the Perseids meteor shower, which peaks on Wednesday (12th Aug)
Zenithal Hourly Rate (ZHR) can be as high as 100 - but because peak time falls at mid-afternoon here in UK, by the time it gets dark, ZHR is likely to have faded off to around 60. Also - as it rises towards peak rate, it may be as high as 40, on the night of the 11th/morning of the 12th. As the name suggests, Perseid meteors emanate from the region of the constellation Perseus. Just as it gets dark, Perseus is low-ish to the North/North-East - and slowly tracks to a point high in the East by about 4am To find Perseus - look high to the North/East for Cassiopeia - a prominent 'W' shape of stars. From the left 'V' of that 'W', look away from Cassiopeia, for two fairly prominent 'wonky' lines of stars, coming to a point - That is Perseus 'Finder' pic Look for Perseids in the areas of the arrows, or even further away from Pereus - Any 'streaker' headed away from Persues, is almost certainly a Perseid http://i29.tinypic.com/2yzltt2.gif As always with meteor showers - you won't see many by looking directly AT the radiant (Perseus) - always best to look about 30° to one side or the other, and more are visible at higher elevations. So - for example - when Pereus is roughly North-East (midnight-ish) - you'll see most meteors by concentrating your gaze either high to the North, or East, or directly overhead, away from Perseus itself. The Moon doesn't exactly play-ball this year though - It'll be a little over half-illuminated on the night f the 12th, and will climb higher as the night goes on, washing out the sky somewhat, and making the fainter meteors harder to spot. Watching sooner after first dark, will probably yield higher numbers of meteors. **note You may also see a meteor or two headed away from a point to the South/South-east - These may be either Aquarids, or Capricornids, which are also active around this time of year, but have a much lower ZHR then the Perseids. You may also see the occasional 'sporadic', which could be anywhere, and headed in any direction. |
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#786 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
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Quote:
Yes that is right. It seemed totally nonsensical.
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#787 |
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Join Date: Jun 2006
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Carlos I have never been lucky yet with meteors. I do not suppose that is going to change any time soon.
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#788 |
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Join Date: Jun 2006
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I guess the fact that the Challenger crew were alive until they hit the water meant that they felt duty bound to implement some kind of escape system.
I take it you are aware of the Russian who was burned in 1961 in a fire similar to Apollo 1? If that had not been hushed up the the Apollo fire might not have happened. |
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#789 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
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That is an interesting point. I am not sure NASA have actually admitted that.
I take it you are aware of the Russian who was burned in 1961 in a fire similar to Apollo 1? If that had not been hushed up the the Apollo fire might not have happened. I am sure the fate of the challenger crew is public in the official report of the accident. |
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#790 |
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Join Date: Mar 2007
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i have no idea when and where to look for these meteor showers
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#791 |
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i have no idea when and where to look for these meteor showers
![]() High to the North, or East. Find a dark spot - away from streetlights - preferably out of town if practical. Take a deck chair or similar, pick your area of sky, and lounge back and relax. Give yourself at least an hour - it takes around 30 mins to get FULL dark adaption of your eyes. Thermos of coffe/soup is a good idea if it's cold. (I have a great spot only 5 mins walk from home - a cemetery, surrounded by thick trees - pitch dark in there, and there's also handy bench-seats to lounge on )Oh - and the word 'shower' is a little optomistic. Occasionally, 'showers' may appear to be just that - but for the upcoming Perseids, don't expect any more than maybe one every few minutes on average. |
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#792 |
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Join Date: Mar 2007
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Quote:
Wednesday night (12th Aug) - after it gets dark.
High to the North, or East. Find a dark spot - away from streetlights - preferably out of town if practical. Take a deck chair or similar, pick your area of sky, and lounge back and relax. Give yourself at least an hour - it takes around 30 mins to get FULL dark adaption of your eyes. Thermos of coffe/soup is a good idea if it's cold. (I have a great spot only 5 mins walk from home - a cemetery, surrounded by thick trees - pitch dark in there, and there's also handy bench-seats to lounge on )Oh - and the word 'shower' is a little optomistic. Occasionally, 'showers' may appear to be just that - but for the upcoming Perseids, don't expect any more than maybe one every few minutes on average. how will i know where north point is in sky
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#793 |
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Join Date: May 2004
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NASA's Kepler Space Telescope sees a planet...
..round a star 320 light years from Earth. This telescope is looking at planets that appear in front of their parent stars in a line of site effect. More on this story here http://www.itwire.com/content/view/26814/1066/.
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#794 |
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Join Date: May 2002
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Quote:
will it only last a few hours
how will i know where north point is in sky ![]() You might see Perseids any time from now, until a couple of weeks time. They're at a pretty low rate most of the time though - the 'Peak' comes on Wednesday, making that the best night. If you have no idea of where North is, then you can find out by looking at the Sun during daytime. Make a mental note of which direction the Sun is at 1pm That direction is not far off Due South. North is the opposite direction. Or stick a pencil in some soft ground, pointing straight up - At 1pm BST (or 12 noon GMT) the shadow points more or less North. |
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#795 |
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Join Date: Nov 2004
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Aha - meteor time again. I'll get my sun lounger out and spend some time sky watching this week then.
Been enjoying the nearly full moon and Jupiter in close proximity over the last couple of nights. With the recent Apollo anniversay observing the moon has taken on a little more sentiment. It just looks so beautiful and inviting - hurry up and go back already NASA! |
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#796 |
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Inactive Member
Join Date: Oct 2005
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Quote:
Aha - meteor time again. I'll get my sun lounger out and spend some time sky watching this week then.
Been enjoying the nearly full moon and Jupiter in close proximity over the last couple of nights. With the recent Apollo anniversay observing the moon has taken on a little more sentiment. It just looks so beautiful and inviting - hurry up and go back already NASA! |
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#797 |
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Those 2 so close in the sky really have been looking good haven't they!
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#798 |
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Join Date: May 2002
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Aye. Had a couple of friends round last night for a BBQ and got the usual 'wow' from them. In my experience you only need to expose a layman to the Moon or Jupiter once or twice and they'll be wanting a telescope for birthday / Xmas. Show them Saturn once and they'll off to the shops the next day!
![]() I showed a neighbour, and his son, Jupiter through a telescope last week. Complete with cloud bands, moons, and the red-spot just appearng round from the side. Following day he was aking advice on getting his son a telescope when Christmas comes round. They were also impressed with the Hercules globular cluster, and the pairing of m81/m82 galaxies - but Jupiter really stole the 'show' |
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#799 |
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Inactive Member
Join Date: Oct 2005
Location: Alacant
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This is quite an interesting read. Looks like something punched through one of Saturn's rings.
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#800 |
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Join Date: Feb 2006
Location: Northern Ireland
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I seen this video on Vimeo and I was wondering, when is the best time to see the Milky way (during the night obviously
, as I assume you cant go out at just any time)http://vimeo.com/4505537 It really makes you feel very small
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, as I assume you cant go out at just any time)