## UKIRT extension

July 29, 2013

UKIRT fans will be pleased to see the announcement here

As UK astronomers will know, UKIRT was slated for closure in September this year, but STFC invited proposals for new operators. The good news is that they have two serious bidders. The bad news is they won’t complete negotiations by September. The good news is that STFC has taken the sane decision to extend UKIRT operation through to December while this process continues. The even better news is that University of Hawaii has swallowed the legal responsibility. (For a suitable one off capital transfer methinks…)

UH also swallow responsibility for JCMT. But that has another year to work things out…

Anyhoo. Tally Ho ðŸ™‚

Update : it seems the news is even better than we thought !

Update next morning : damn. STFC got tough again

## Raindrops, stars and photons

July 29, 2013

Here is another one of those occasional posts with mazin facks bout stronomy. (See also Almost Nothing and A Dim Glimmer).

Today’s rambling is inspired by some fascinating tweets emitted by darkskyman aka Steve Owens of Dark Sky Diary fame. First I will give you the gist of Steve’s ‘believe it or not’ sequence. From the average rainfall in the UK last year (1.33m), the area of the UK (2.426×10^11 m^2), and the average volume of a raindrop (10^-9 m^3) he calculated that the total number of raindrops that fell on the UK was 10^20. That is a big big number. However, continues Steve, the number of stars in the Universe is approximately 10^23.

So as Steve told us ‘for every raindrop that hit the UK last year there are 1000 stars in the Universe’.

Very nice, but I found myself thinking – how does the rate of raindrops compare to the rate of photons? The average raindrop flux is 13 raindrops/m^2/s. Lets compare to the Sun. The solar constant is 1360 W/m^2. If we take the typical photon as being at about 500nm with energy hc/lamda = 4×10^-19J, we get roughly 3×10^21 photons/m^2/s.

So we get much much much more sunlight than rain! Woohee!

What about starlight? Well, as Mr Olbers pointed out, a Universe full of stars would make a sky as bright as the Sun in every direction. However, the Milky Way fades out, and the universe runs out too, in time and therefore space. So lets just get empirical. Cosmology types will often plot the ‘cosmic optical background’ at a level of about 10^-8 W/m^2/sr, about a factor of a thousand less than the CMB. However, that is the extragalactic background light;Â  the summed emission from nearby stars is in fact much more. According to my Trusty Allen, star light from the whole sky is equivalent to 460 V=0 stars, or one star of V=-6.7. TheÂ  apparent mag of the Sun is V=-26.7. So the scattered starlight is 20 magnitudes fainter or a factor of 10^8.

So in super-crude terms, starlight is giving us something like 3×10^13 photons/m^2/s. Still lots more than the 13 raindrops/m^2/s.

But what energy? Scaling down from the solar constant, starlight is giving us an energy flux of about 1.4×10^-5 W/m^2. What about raindrops? Each of those raindrops has mass 10^-6 kg. The terminal velocity of a raindrop depends on size, but at 1mm its about 4 m/s. So the KE per raindrop is about 8×10^-6 J and the energy flux is therefore 10^-5 W/m^2, about 6 times as much as starlight.

So… in particle count terms, the Sun wins hands down; starlight is down a factor of hundred million but still huge; and the raindrop count is pitiful, another factor of a trillion down.

In energy terms, the Sun still wins easily, with starlight a hundred millions times down; but the rain carries more energy than the starlight – just.

Please do check the maths… Anyhoo. Better do some real work today.

## Science, Money, and Derring Do

July 11, 2013

Lots of readers for NAM and the Knife Edge, but only one comment. Maybe its a summer thing. The other Professor L expressed his surprise that I didn’t get whingeing about the Edinburgh footie victory.

Meanwhile, over in US-land, less than flat cash for the NSF is being hailed as a major victory. Typical government cuts are 5%, but NSF has “only” 2.1%. Thats before inflation folks. It includes \$232M for Astronomy in FY2013, as we can see here. This is probably stage 7B in the 11 stage horse trading process or something. US politics and bureaucracy is very hard to follow. Anyhoo. I am crossing fingers for the LSST kick-off.

Back in the realm of her Brittanic Majesty, if you really want to see how research funding works, the NAO (isn’t that the Nautical Almanac Office? – Ed.) has released a very informative report which you can find here. I think the bottom line is that our R&D per unit GDP is slightly better than Kazakhstan or something like that. This perfectly simple flow diagram explains everything.

How R&D funding works in the UK

Because science funding is so depressing, I have been retreating into entertainment. Rather than my usual habit of finding old records, I went out and found some old books. I just read a 1930 copy of the 1916 book Greenmantle, the Ripping Yarn that John Buchan wrote after The Thirty Nine Steps. Its a spy story set in the middle of the First World War, climaxing at the battle of Erzerum. Interesting and confusing. I kind of expected an Edwardian book to be written in turgid and complicated sentences, kinda like Dickens or Scott I suppose, but in fact its in short punchy very lively style. It really rattles along. I also expected it to be jingo-istic and full of racist stereotypes. Well it is. But it is also full of surprising insights and sympathies for ordinary Germans, and for Islam. A very interesting post was written on this topic by Jeremy Calder at the Liberal England blog. I can’t say it better, so visit that if you are interested. It seems really surprising that Greenmantle has never been a movie.

## NAM and the Knife Edge

July 5, 2013

Had a jolly few days at NAM2013, the annual UK astronomy jamboree. I gave two talks, a contributed talk and a plenary. This was hard work. Stress City. But I got through it and even enjoyed myself with a giant broom-pointer gag. Later the same day, the Edinburgh team won the NAM footie, beating St Andrews 6-1 in the final, so smiles all round this side of the Firth of Forth. Thanks to Duncan Forgan for the piccie.

Wednesday afternoon was the STFC community session. John Womersley gave an upbeat talks on the state of STFC but the community was left rather nervous. Here are a few key points :

• Because of the upcoming election, the spending review is for 2015-16 only. The long term funding is all still to play for.
• The science budget has its allocation (flat cash plus a teensy bit of extra capital) but the Research Council carve-up is still to come. My giant mop may be needed to clean up the blood.
• The STFC budget result will come in September, same time as the STFC programmatic review outcome is announced. I guess this means that we still won’t know whats in and whats out…
• Three years ago flat cash seemed like a victory. This time it could look more like disaster. The longer it continues, the more inflation erodes. As erosion continues, at first you just lose some soil – but there comes a day when the cliff collapses. Womersley uses a different metaphor. He said he is telling government that we are on a knife edge. There are rumours that ISIS may have to be mothballed. Wouldn’t make my high-pressure chums very happy…
• JCMT is now up for sale. (See also SEN article). Meanwhile STFC are negotiating with two serious potential new owners for UKIRT. It seems unlikely this will conclude before the axe is due to fall in September, so there may be a temporary stay of execution.
• We need to make the case to Government for our economic relevance. Well ok, we have all heard this again and again, but Wommers had a potentially important new idea. We need quantifiable metrics – somewhat along the lines that a road building project might use, quoting the number of commuter-hours saved and attaching a pound-note figure. This won’t be easy, but it really is necessary. You see, I think most politicians are already convinced that science is important, but this warm feeling doesn’t tell them whether they need to spend N pounds or 2N pounds or 0.5N pounds.

Well that will do. For those with a Research Fortnight subscription, there is an excellent article just out by James Wilsdon from Sussex with some interesting insight.

Meanwhile, just to show that it is technically possible to balance permanently on a knife edge, here is Emerson Lake and Palmer forty years on. A treat for prog rock fans. Janacek fans still divided.