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PhilW wrote:is the top left star in Orion usually a distinctly different colour (orange/yellow) to the (blue/white) others?

Yes, that is the red super-giant Betelgeuse. If you stick around for 100,000 years you will see it blow up to become a supernova that for a few days could be visible in daylight and brighter than the Sun.

PhilW wrote:I took a few shots of the sky in general as well

So did I - this is a single frame 1 minute exposure of the Orion Nebula at 12,800 ISO...

I'm disappointed that there's no mention here of the fact that Matt Damon appears to have dug a well on Mars. Surely yesterday's press announcement deserves some acknowledgement?

AHB wrote:I'm disappointed that there's no mention here of the fact that Matt Damon appears to have dug a well on Mars. Surely yesterday's press announcement deserves some acknowledgement?

Indeed. A very small part of Mars has been found to be slightly salty and damp.

DRT wrote:

AHB wrote:I'm disappointed that there's no mention here of the fact that Matt Damon appears to have dug a well on Mars. Surely yesterday's press announcement deserves some acknowledgement?

Indeed. A very small part of Mars has been found to be slightly salty and damp.

Water recently flowed on Mars, that is reasonably exciting, especially with regard to the possibility of extremophiles.

LGTrotter wrote:is reasonably exciting, especially with regard to the possibility of extremophiles.

In reading about the possibility of extremophiles, and comparing them to those on Earth, it seems to me that much widely-available reasoning misses a step.

On Earth, in nasty places, there is still life. Hence, the reasoning goes, there will be life in non-Earth nasty places.

Yes, but…. Really, ‘but’. The nasty places on earth are next to nice comfortable wet cosy places. Neighbouring the Earth’s rough neighbourhoods are nice neighbourhoods, in which might be the microbiological equivalent of Toad Hall. So the little fellows set out from cosy and wet Toad Hall, and evade the predators by living near—but not really in—the nasty places. They adapt. They become better able to tolerate extreme hot/cold/acid/alkaline/dark/heat-damaged Port/light-damaged Port/2,4,6-Trichloroanisole/badly-rinsed glasses/sudden deficiencies of cheese/even worse. Then, having evolved to tolerate these terrible traumas, their offspring venture even further into the nastiness — that is, away from their predators. Some, of course, come to a sticky end in the extremophile version of Bolognese. But some don’t, and last long enough to have offspring that can then evolve further tolerance.

But on far-off places, there is no asylum from which many attempts at colonisation can be ventured. There is only the nasty. Start there, in the middle of there at full-strength no-mercy not-even-Toad-Hall’s-cellar nastiness. Die. No life remains.

This reasoning appears to not be part of the standard optimism about alien life and extremophiles. Especially the bit about badly-rinsed glasses.

It is of course possible that anything that is alive in the cold, salty, damp nasty places on Mars are the last remnants of the evolutionary relative lifeforms that might have existed in better environments when Mars had a thicker atmosphere, surface water and a warmer climate. Somewhat counter-intuitively, the extreme nastiness might have served as a safe haven when all else was lost.

DRT wrote:Somewhat counter-intuitively, the extreme nastiness might have served as a safe haven when all else was lost.

No. You would not be pleased if the last bottle in your cellar had TCA. If Mars had somewhere damp and cosy, then things could have evolved as Mars deteriorated. But extra nastiness is always bad.

jdaw1 wrote:

DRT wrote:Somewhat counter-intuitively, the extreme nastiness might have served as a safe haven when all else was lost.

No. You would not be pleased if the last bottle in your cellar had TCA. If Mars had somewhere damp and cosy, then things could have evolved as Mars deteriorated. But extra nastiness is always bad.

I think you have missed my point.

Mars is warm and hospitable - life begins and evolves into many forms of slime. Some of the slime takes up residence in extreme places whilst its cousins bask in nice places.

Solar wind >> atmosphere gone >> planet core freezes >> no more volcanoes >> brrrrr! it's freezing and I can't breathe! >> everything dies >> except the extremoslime.

Ah, so it isn’t that bad places are good; it is that bad places are where ‘extremoslime’ gets trained. No objection to that.

Having actually read the story rather than the headline it seems they think that water currently flows seasonally on Mars, albeit with some rather odd salts in it.

LGTrotter wrote:Having actually read the story rather than the headline it seems they think that water currently flows seasonally on Mars, albeit with some rather odd salts in it.

That is indeed what has been postulated. I haven't seen anything that defines the seasonality of this phenomenon. Is it daily, monthly, annually or spread over a number of years?

Without doubt this is a significant discovery, but the hype seems to have been more than was necessary for a thing that has been suspected for such a long time.

The launch of the Hollywood blockbuster "The Martian" 36 hours after the big announcement about water we knew about is clearly a coincidence that will have no effect whatsoever on popular opinion or government funding for a manned trip to Mars.

DRT wrote:Without doubt this is a significant discovery, but the hype seems to have been more than was necessary for a thing that has been suspected for such a long time.

Quite correct.

DRT wrote:The launch of the Hollywood blockbuster "The Martian" 36 hours after the big announcement about water we knew about is clearly a coincidence that will have no effect whatsoever on popular opinion or government funding for a manned trip to Mars.

Quite wrong.

And what a waste of money. It’ll cost a few hundred Curiosities/JamesWebbs/whatevers, do less science, and contaminate the planet. But the work will be given to companies in the constituencies of important politicians; the companies will give some of the money to the senators; and the corrupt wheel will turn.

So, so cynical. I thought space was meant to inspire us?

djewesbury wrote:So, so cynical. I thought space was meant to inspire us?

The James Webb telescope will cost, indeed has already cost, a fortune. But might be fantastic. It is not about romance—mad adventurers and dashing heroes—it is about cool hard science. Do it!

Man on Mars (and those who ‘self-identify’ as ‘politically-correct’ will squabble about who is to go and who is ‘under-represented’) is a waste of money and effort.

You want to spend money of a good programme? Do things in bulk. Cassini, times four. Uranus, Neptune, and a slow ‘orbit around’ a Jovian L₄/L₅ Lagrange point. And a spare: if the first three make it off the ground in good order, send the spare to the other of L₅/L₄. The spacecraft don’t have to be identical, but the aim should be 80%+ in common. The only weakness in this plan is the plutonium.

With regards to seasons on Mars I assumed that they meant the same as on Earth, ie winter, summer etc on whatever timeframe Mars has.

With regard to the alleged futility of sending manned spacecraft to Mars, I would vigorously disagree with Julian. They had a lovely Horizon programme on the Beeb the other day in which they sent a rover around a fossil rich piece of desert. The rover found none of them, a person would have seen many in a few moments. There are of course some things which unmanned craft can do better. But there are still some things which only people can do. This is without the obvious 'because it's there' retort, which is as meaningful as any other.

I agree with Julian and Owen.

We should be sending lots and lots of robots into space to send back pictures and scientific data to help us understand what is out there. But we should also send people to carry our proper exploration. Both of these things are much better than shooting one another.

DRT wrote:I agree with Julian and Owen.

Coward. Whilst I would not wish to put words in the mouths of other people it seems plain that you agree with me and not with your life-coach. I say unmanned probes but also manned missions, as do you, it is Julian who would have us all stay at home while the bots have all the fun. And while I am cynical about almost everything I ought to be allowed the odd blind spot, brought up on sci-fi I marvel at what has been achieved in space. I refer readers to 'How Russia won the space race' on BBC4 if any doubt the individual courage and technical challenge of what has been done already.

LGTrotter wrote:it is Julian who would have us all stay at home while the bots have all the fun.

Not quite. The problem with people in space is that they require all this oxygen, warmth, water, food, not being exposed to space, protection from micro-meteorites, protection from solar rays, and other really expensive stuff. Really really really expensive stuff. For the price of a few astronauts about as far from Earth as is Dublin from London, you can have one spacecraft doing a fly-by of Pluto. Choose one!

Do not, just do not, suggest the other-people’s-money-is-no-object plan of ‘both’. Because the ‘other people’ whose money is at risk might have something to say.

Calm yourself Julian, my influence on the resources allocation committee of NASA is not as great as once it was.

Anyway, I refuse to be troubled by your demands to comply with these stultifying binary options. To quote your beloved Oscar; "We are all in the gutter, but some of us are looking at the stars"

I chose both. Back to your bean counting.

My new canon has arrived...
We can expect 100% cloud cover over the UK for the next 40 nights

DRT wrote:My new canon has arrived...

Looks like a beast; what size is it? (looks like ~15" diameter and close to 5' long!)

DRT wrote:We can expect 100% cloud cover over the UK for the next 40 nights

Following the clear skies and the northern lights visible as far south as Yorkshire and Wales in the last couple of days, I might have been tempted to do a lot of driving this weekend if only the skies were going to be clear and the lights visible on Saturday night, but it currently looks like cloud everywhere; the forecast says it should be clear tonight, then cloudy (forever) - you jinxed it!

PhilW wrote:

DRT wrote:My new canon has arrived...

Looks like a beast; what size is it? (looks like ~15" diameter and close to 5' long!)

It has a 406mm (16") diameter mirror and a focal length of 1800mm. The telescope and base have maximum physical dimensions of 77cm (base diameter), 56cm (tube diameter) and 190cm (top of tube at zenith). It weighs around 60kg. Someone of average height needs to stand on a step in order to look through the eyepiece.

It is indeed a beast.

DRT wrote:It is indeed a beast.

It needs a camera.

It has access to one of these.

Manually-driven Dobsonian telescopes are not favoured by astro-photographers as they cannot be used to track an object to allow long or multiple exposures, but I should be able to get some good one-shot pictures with it.