oas astronomy e-zine nov 2013

8/14/2019 OAS ASTRONOMY E-ZINE NOV 2013

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Petition for the Open University to offer MSc in

Astronomy/Astrophysics

With all the recent changes to higher education funding, times are pretty toughwith some very uncertain futures for most upcoming science graduates, there iscurrently a massive ‘Postgraduate Gap’; the number of postgraduates, especiallyin the sciences, is dwindling with a quickly increasing average age of academics in

the UK.The value of higher education is something that can be clearly visualised andseen; every science and engineering graduate brings back ~£1 million in their life-time. The demand for such graduates is bound to increase with every decadethanks to advancements in technology, and this is where the postgraduate gapslots into the giant puzzle, there is no funding for postgraduate Master’s degreeprogrammes unless you were enrolled on one as an undergraduate or received abursary/scholarship. Not only is it expensive, but if you have work commitments/family commitments/health problems, then doing one full-time becomes essential-ly an

impossible task, that’s not even taking into account commuting/living costs if theUniversity is not nearby.The Open University however with its years of experience in part-time distancelearning might be a solution, hence why I’m petitioning the OU to construct aMaster’s of Science degree scheme in Astronomy/Astrophysics, a subject that theOU also has had many years of experience lecturing and teaching. Not only that,but it has quite a few excellent tools in order to perform observations remotelyfrom your own home!The OU’s robotic telescope, known as PIRATE (Physics Innovations Robotic Astro-nomical Telescope Explorer), is based in Majorca, Spain and presents an excellent

remote interface for communicating with the dome, instruments and telescope it-self. There is a planned robotic radio telescope being calibrated and fitted at themoment with the OU, there will even be eventual access to the public thanks tothe new ‘Open Science’ programme. The OU is therefore a perfect and ideal remedy for helping to broaden access tophysics and astronomy whilst solving the gap in postgraduates; the courses arecheaper, there are no additional living costs/hassle of moving away (again), latesttechnology, can do it in your own time (earn while you learn) and you receiveplentiful amounts of support as an OU student.So if you value education and giving prosperity to the future minds of Astronomy

and Physics, please support the petition for the Open University to Construct anMSc in Astronomy/Astrophysics.

Lawrence Bilton



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Are you in need of some Help & Advice? This month we are going to

Have a look at polar aligning your telescope mount with advice

from Mike Greenham

Image Source:http://www.ashbydelazouchmuseum.org.uk/Tudors.html

http://www.ashbydelazouchmuseum.org.uk/Tudors.html









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Polar Aligning an Equatorial Mount The following procedure shows the polar alignment of an NEQ6 mount. This

procedure can be adapted to most equatorial mounts.

Step 1 : Place the Tripod in position so that the

locating lug seen in this picture is facing roughly North.

If you are using your telescope in the same place every

time, ie a patio, it’s a good idea to mark the patio in

some way so you can quickly put it back in the same

position each time.

Step 2 : Level the tripod in all directions. I use a

small level as this is much more accurate than

the bubble levels built into mounts. Once this is

done place the mount head on the tripod and

tighten the bolt underneath

Step 3 : Roughly set your altitude using the

altitude bolts. You can find this info using

your phone/ Google maps etc. I use a freeapp for the iPhone called Scope Help that has

a few useful features .

The following steps 4, 5 and 6 only need doing the first time you set up the

mount.

Step 4 : Now loosen off the RA clutch and rotate the mount though 90 degrees.

Place the level on the

counter weight shaft and get it perfectly level before locking the clutch. Adjust

the RA clock by loosening the

small screws and

rotating the clock ring until the

arrow is pointing to 6 o’clock

and lock the ring in place. Now

loosen the RA clutch again and

rotate in RA so that the clock



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shows 12 o’clock. The counter weight shaft should be

now facing down. Take a black permanent marker and

transfer a mark onto the mount as shown in the

picture on the left. This has now marked the home

position in the RA. When your black mark is in line

with the arrow your mount is vertical. We need to do

this because in further step we will be moving the RAclock.

Step 5: With the RA still at 12 o’clock we will now set the

declination clock. Loosen the Dec clutch and rotate until

you can place the level as shown. Get this perfectly level

and lock the Clutch. Now adjust the Declination clock as

we did above setting it to 90 degrees. There is no need to

mark anything as this clock has no need to be moved

again. Now if you rotate the declination so that the clockreads 0 you mount will be exactly in its home position.

Step 6: Now have a look into the polar scope.

You will see something very similar to the image

on the right. You can see Polaris is clearly

marked as a small circle located on a large cir-

cle. Polaris isn’t actually stationary in the sky. It

follows the path of the circle in the image. Loos-

en the RA clutch and rotate the mount in RA un-til Polaris is at the 6 o’clock position as shown in the image. Lock the clutch and now

go back to the RA clock and set it to 0. This clock is now set and should be tightened

as we won’t be moving it again.

Step 7: Move the mount back to its Home position and put on your counter weights

and scope and make sure everything is nicely balanced. Do this by firstly loosening

the RA clutch and rotating the mount in RA. It

should stay in any position you put it in. If it isn’t

balanced it will swing so that either the weights go

down or the scope does. Adjust the weights to

obtain perfect balance. Next lock the RA in the

position in the picture and then loosen the

declination clutch. Now balance the scope by

moving the dovetail within the mount or by sliding

the telescope within the tube rings.

Step 8: Ok now we are ready to turn on the mount and align with Polaris.

If you haven’t got the Synscan handset then skip this step and obtain Polaris’s



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position using your chosen method. Once you turn on your mount the handset will

greet you with the version of software it is running before asking you to enter your

location, time zone, date, time and daylight saving. Daylight Saving is British

summer time so answer yes in the summer when the clocks have been moved

forward.

Once we have entered all the above we will be

faced with this screen. It tells us the last time

Polaris transited (passed through the 6 o’clockposition in our polar scope). What we do is

loosen the RA clutch and rotate the mount in

RA so that the RA clock shows the time shown

at the top of this screen (00:24 ie 24 minutes

past midnight). Lock the RA clutch and now

look through the polar scope. By using only

the altitude and azimuth bolts move the

mount so Polaris is

dead centre in its little circle. Depending on the Polaris timethe small circle will be in different positions so don’t worry if

it doesn’t look like my illustration.

That’s it. Your mount is now Polar aligned and should track

the night sky with a good degree of accuracy. After you have

exited after this screen the handset will ask you if you want

to begin alignment. If you answer yes it will give you the

option of using 1, 2 or 3 stars. If I am imaging I normally

only align on 1 star, choosing one that is near my target. If I’m just going to visually

browse the sky hoping from one target to the next then I complete a 3 star

alignment. I find that this then brings most objects nicely into the field of view when

using the goto feature.

Words & Images Mike Greenham



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After writing the first article on the Royal Society, it seemed in

order to do the institution complete justice another follow on was

needed.

As a brief recap to the first article, the Royal Society was formed

one wet November day in 1660 at Gresham College, where 12 people thought it might be a good idea to form a society which

specialised in Science and its development of knowledge. Christo-

pher Wren (then 28) was giving a talk on Astronomy when the idea came about.

This has never been done before, and would never be done again in this manner. The Society as the or-

ganisation become know, became the “Royal Society” after receiving its charter from King Charles II in

1662. The Royal society then went on to invent scientific publishing, peer review systematised experi-

mentation. Brought about clarity in reporting and collated some of the best thinking minds in the world

and in doing so, invented modern science.

The Royal Society took an interest in all manner of things scientific from the behaviour of gases to the

development of the pocket watch.

Christopher Merrit invented a way of fermenting wine twice, in doing so invented champagne.

John Aubrey contributed a paper on ancient stone monuments in Avebury and in doing so started the

field of Archaeology.

Three major things set the society apart

The society was always truly international. For example German Born Henry Oldenburg became

editor of the Royal Society’s first Journal (one of 7 in fact). The Philosophical Transactions It was this synergy that resulted in the Royal Society receiving offerings of papers from abroad,

from Christian Huygens for example. So ideas could be exchanged globally

The Society also remained neutral in all its dealings taking no political or religious bias. This fact

was neatly demonstrated when Napoleon asked Humphrey Davy to attend to an issue he had in

France, during the Napoleonic wars. A letter was passed to him, granting him safe passage

through France. Much to the brief concern of his then apprentice Michael Faraday.

This was highly unusual in those days, however the third major feature that separated the Royal So-

ciety from other institutions was that fellows did not need to be financially well off in order to be

elected. Certainly it helped to be wealthy however if you were to demonstrate knowledge, skill,

and ability in science this was enough to gain fellowship within the Royal Society.

An example of point 3 was Leeuwenhoek had virtually no education, lived in Holland, and yet with a

crude Microscope was producing some fine drawings of how the micro world appeared. Possibly

being one of the first to observe bacteria.

Perhaps one of the most amazing feats of the Royal Society was to elect fellows before they them-



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selves became household names. For example Charles Darwin was elected 3 years before his trip on

the Beagle, Edmund Halley was elected before he received his degree from Oxford. William Henry

Fox Talbot was elected two years before he invented Photography.

It is hard to write an article of this nature for an astronomy magazine keeping it on an astronomy

bias, however this as I am sure you have discovered is not easy to do since the Royal Society had

interests and did great things in various fields not just Astronomy.

One could not discuss the Royal Society in The OAS Word without mentioning something about

Isaac Newton. To give Sir Isaac Newton the treatment he deserves (though he was not a very nice

man) would require another article.

To delve further into the Royal Society would require a book in itself, never mind a magazine article.

However it seems to be fitting to conclude by saying:

The Royal Society still has as pivotal role to play today in Science. In fact as a keen scientist myself I

have often thought that after winning the Nobel Prize and gaining membership to the Royal Society one

has reached the pinnacle of their career.

For the Society now sponsors

350 Research fellowships

awards, many medals and priz-

es, is involved in countless de-

bates on all manner of subjects.

Supports some 3000 scientists

in their work and runs the Sum-

mer Science Exhibition.

References

Seeing Further, By Bill Bryson,

published Mixed Sources, 2010



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LOOK UP!

A GUIDE TO

THE STARS

Welcome to longer and darker nights, yes the clocks have gone back onehour (GMT). Here at OAS we have

put together a small guide forcosmic bodies to view this comingmonth. The big event of the monthand possibly this year will be CometISON.



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15/11/2013

THE MOON

The new Moon will rise in Scorpio at 06:55 and set at 16:22 on Sunday 3rd. Firstquarter will be in Aquarius and will rise at 12:39 and set at 22:35 on Sunday 9th.Full moon occurs on Sunday 17th, it will rise in Taurus at 16:06 17th and will set08:13 on Monday 18th. Last quarter will occur on Monday 25th it will rise at 23:26in Leo and set on the 26th at 12:44 in Virgo

Planets

Mercury is low in the morning sky on the 13th @ 05:42 moving higher in the sky

just before sunrise, caution is needed when viewing Mercury due to its positionclose to the Sun.

Venus rises in the SE and is low to the horizon at 12.21, by 16:27 on the 5th Venusshould be visible with the unaided eye however it becomes quite clear by themonths end in the early evening.

Mars will be observable during the early morning this month at around 01:30 onthe 1st. Look out for Comet ISON near by.



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Jupiter moves through our morningskies throughout the month. On the20th at around 03:40 you will be able tosee Jupiter, Moon, Orion, Sirius andMars looking east panning round to thesouth.

Image: Mike Greenham

Saturn lies close to the sun this monthas viewed from the Earth and viewingwill be very difficult.

Uranus for those with more powerfultelescopes will be in the SW in the earlyhours on the 1st before moving below the horizon at approximately 04:20. On the13th the Moon may viewing Uranus difficult after midnight. Uranus remains in the

morning sky throughout November, however it will be low to the horizon by the 1stDecember.

Neptune while faint is moving south on the 1st at 18:30, it remains in the earlyevening sky all month.

Comet C/2012 S1 (ISON)

Credit: NASA/ESA,/J.-Y. Li (Planetary ScienceInstitute), and the Hubble Comet ISONImaging Science Team

ISON promises to be the show stopper of theyear, throughout November ISON will beseen in the early morning sky looking East.

Sky Notes by David Bood information from Stellarium software. This is a guide only.



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An artist’s impression of the black hole in Cygnus, with matter falling into the black hole.

Calculating the escape velocity

Newton’s law of gravity allows us to calculate the force of gravitational attraction between two

bodies of masses and . It is simply . Let us suppose is the mass of the

Earth, which we are now going to call ; and is the mass of an object on the Earth’s sur-

face, we are going to call this second mass just . In order for the object on the Earth’s surface

Wh at is a black hole?

Posted in Astronomy, Physics, Science, tagged Black Hole, Neutron Star, White Dwarf on 13/07/2013 | Leave a Comment »

Last weekend was a pretty big sporting weekend. Not only was there the Third and deciding test of

the 2013 Lions’ tour of Australia, but there was also the men’s and women’s finals of Wimbledon,

and the German Grand Prix. As far as I can tell there is no sport going on this weekend. Before

someone comments below that England are playing Australia at cricket in the First Test of the Ash-

es, I should remind my readers (all 2 of you) that a bunch of overweight men standing around for 5

days not doing much does not constitute sport. So, with this lull in the sporting calendar, I thought

I would write this post about black holes, which I have been meaning to do for a while.

Nearly every one has heard of black holes, but what actually are they? And do they actually exist?

Well, a black hole gets its name because it is an object from which not even light can escape. The

radiation (light and other forms of electromagnetic radiation) which the central part of the black

hole gives off is not able to escape the extreme gravitational field the black hole creates.

http://thecuriousastronomer.wordpress.com/2013/07/13/what-is-a-black-hole/

http://thecuriousastronomer.wordpress.com/category/astronomy/


http://thecuriousastronomer.wordpress.com/category/physics/


http://thecuriousastronomer.wordpress.com/category/science/


http://thecuriousastronomer.wordpress.com/tag/black-hole/


http://thecuriousastronomer.wordpress.com/tag/neutron-star/


http://thecuriousastronomer.wordpress.com/tag/white-dwarf/


http://thecuriousastronomer.wordpress.com/2013/07/13/what-is-a-black-hole/#respond


http://thecuriousastronomer.files.wordpress.com/2013/07/sygnux-black-hole.jpg








http://thecuriousastronomer.wordpress.com/2013/07/13/what-is-a-black-hole/



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is , and we shall use the radius of the Earth that we used

above, . These numbers give

us which is 2% of the speed of light.

The escape velocity from a neutron star

A neutron star is the end produce of more massive stars. The Sun is not massive enough to become

a neutron star, but a star which is more than about 3 times the mass of the Sun is. In a neutron

star all the space that exits in atoms is squeezed out, so it is essentially a pure lump of nuclei. A

typical neutron star may have the mass of 2 Suns, but squeezed down into something the size of a

city! So, for our calculation, we are going to assume a 2 solar mass neutron

star, . For the radius we will assume 10km,

so . Plugging these values into the equation for the escape velocity

gives which is 77% of the speed of light.

The event horizon of a black hole

The escape velocity from a neutron star is still below the speed of light. Pulsars are produced by

radiation from the surface of a neutron star being beamed past us as the neutron star rotates. So,

we have direct observational evidence that we can see radiation from neutron stars.

But, in the same way that a star which is a few times the mass of the Sun will end its life as a neu-

tron star rather than a white dwarf; an even more massive star will not end as a neutron star. This

is because of something called theneutron degeneracy pressure. To put it simply, this is a physical

law which says that neutrons do not all want to be in the same place. They resist this through a re-

sistive component in the strong nuclear force. But, if a neutron star were to have more than about

3 times the mass of the Sun, the gravity is strong enough to overcome this neutron degeneracy

pressure. There is no known force to stop the collapse of the neutron star, and this is what forms a

black hole.

We can work out the radius at which the escape velocity becomes equal to the speed of light for an

e.g. 2 solar mass black hole. This is the same mass as our neutron star example above. But, as we

shall see, it will need to be smaller than the 10km size of a neutron star. The radius at which the

escape velocity is equal to the speed of light is what we call the event horizon of black hole.

To do the calculation we just re-arrange our escape velocity equation to

find when where is the speed of light. The re-arrangement is that .

For , and we find the radius of the

event horizon to be . Notice how close this is to the actual size of

a typical neutron star, just a little over half the size. It shows how little mass has to be added to a

neutron star to tip it over the edge into becoming a black hole.



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Notice that all of the above calculations have been done assuming Newton’s law of gravity. Newton’s

law of gravity is not actually correct, it has been superseded by Einstein’s, which we call the theory

of General Relativity . To do the calculations properly we should use this theory, but it is rather com-

plicated. No, it is very complicated. But to illustrate the basic idea, Newton’s laws are fine. It is sur-

prisingly often said that Einstein’s work led to the prediction of black holes. This is not true, they

had been suggested by a geologist by the name of John Michell in 1783. But we do need Einstein’s

work to do the calculations properly.Any radiation being emitted from inside of the event horizon will never get to us, the gravitationalpull from the black hole stops it from escaping. How do we therefore even know that black holes ex-

ist? I will answer that question in a future blog, along with some discussion of what happens asmatter crosses the event horizon of a black hole, and what might be right at the centre of a blackhole.

Image of Sgtr A* the black hole at the centre of the Milkyway, as seen by the Chandra X-Ray Ob-

servatory

http://en.wikipedia.org/wiki/File:Chandra_image_of_Sgr_A.jpg






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Like many amateur and professionalastronomers alike, I am excited about viewing comet ISON. If the hype turns outto be correct then we may be able to see this wonder with the unaided eye. Before

we get into what a comet is and some details on the comet, let’s have a little lookat some of the myths surrounding comets from bygone years and present daymyths, and to some extent scare mongering that has popped up on the internetand mainly YouTube.

Before humanities understanding of the cosmos, before our understanding of na-ture, humans associated things that they did not understand with the paranormal.Be it a solar eclipse, Vikings thought they had angered one of their Gods, and theGod was swallowing up the sun, they would chant or scream at the sky and ofcourse the eclipse would come to an end. Today we know what natural event caus-es solar and lunar eclipses.

Comets were thought by some ancient cultures to be the harbingers of doom, ormessengers from mythical Gods. Today we have the power of global communica-tions, and such stories and myths pop up on places like YouTube. One such storyis NASA is covering up what comet ISON really is! Believers or conspiracy theoristspropagate a myth about a rogue planet that sweeps through our solar system eve-ry 3600 years called Nibiru or planet X. They believe that ISON is this planet orbrown dwarf star.

However all these claims are baseless and untrue, Comet ISON is just that, a com-

et.

Comets have been dubbed ‘Dirty Snowballs’ but why? Comets are interesting ce-lestial bodies; they originate out in the Kuiper belt and Oort cloud region. This areais the outer limits of our solar system, where it is cold. Gravity pulls togetherlumps of rock, dust, gases and water* to form these dark bodies. * water is frozen

It is thought like asteroids, comets were formed with leftover material from whenthe solar system was formed. Comets are hard to detect from Earth, they aredark or have a low albedo.

“Albedo- Reflection coefficient, In Latin means Whiteness or reflecting

power”

Comets can orbit the sun much like planets, however there orbits can be long andtake many thousands of years, or once in a lifetime opportunities to view like Hal-ley's comet. Comets can also sit out in the outer reaches and events such as a col-lision can send those inwards.

It is only when they venture into the inner solar system that comets start to be-

come more visible, certainly more visible to the amateur astronomer. As theymove in, energy from the sun in the form of the solar winds and radiation pressurecauses the volatile gases and ices to melt. The main body of the comet, the nucle-



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us forms a thin atmosphere around it called the ‘coma’, the energy from the sunacts on the coma forming a tail. While the nucleus can be up to 60 km across thecoma can be as big as the sun, and the tails can stretch for thousands of kilome-tres. The Coma and tail have a high albedo, the ices, gases and water are nowvery reflective which for astronomers is a good thing as we can now observe thecomet. One thing to mention the tail points away from the heat source.

Comet - Chemical Composition

It is possible that comets were responsible for bringing water and life to planetearth. Astronomers and scientists now know there is plenty of water out there inthe cosmos be it in a frozen state and as hard as rock. However comets are madeup of frozen gases too. These gases include carbon monoxide, carbon dioxide,ammonia and methane. Other properties include compounds such as methanol,hydrogen cyanide, formaldehyde, ethanol and ethane. Comets also can containmore complex molecules such as amino acids (building blocks of life) and long

chain hydrocarbons.

Comet ISON (C/2012 S1)

Discovery: 21st September 2012 by two Russian astronomers working for the theInternational Scientific Optical Network, their names are Vitali Nevski and ArtyomNovichenok.

Dubbed the comet of the century, ISON could be a truly spectacular comet. Onthe 1st October 2013 @ 17:27 UTC ISON made its closest approach to Mars, and

passed within 6.74 million miles. Through October it has an average speed of78,717 mph and will continue to accelerate until the 28th November where it willspeed up around the sun to a staggering 845,000 mph.

Size: Approx 3 miles in diameter, conclusion from data analyzed by NASA’s swiftsatellite.

Viewing

The comet will pass within 1.2 million miles of the suns surface on the 28th No-vember 2013 when it reaches perihelion. On its outward journey it will pass overthe Earths northern hemisphere at a distance of 40,000,000 mile on the 26th De-cember. If estimates are correct you should be able to observe the comet with theunaided eye anywhere between November 28th 2013 and January 2014, depend-ing on your location.

Clear Skies!

Dave Bood

Sources NASA, www.cometison2103.co.uk

Image by Hubble Team.

http://www.cometison2103.co.uk/

http://www.cometison2103.co.uk/



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Mike Greenham



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Mike Greenham



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Capturing the full disc of the Sun.

Andy Devey

This month I thought that I should cover how to capture the Sun’s full disc. TheSun is a very large target and beyond the size of most CCD chips in the videocameras that are now available to the amateur astronomer. Some of my friends

use the larger chips in their SLR’s to capture the full disc through a telescope butthese cameras have colour CCD chips and this will wash out much of the detail thatis available to the monochrome CCD chip. The options available to today’s amateursolar astronomer are dependent on the personal goals that individuals set in thisfield.

Some of my friends have opted for large frame CCD cameras such as the newDMK51 combined with a focal reducer such as a 0.5x Barlow, this will allow theuser to shoot full frame video of the full solar disc. With this option everypart of the Sun is shot at exactly the same time a real must with such a

dynamic target in the field of view. Further the processing required toachieve the complete photo is restricted to just a few minutes. Onefriend uses this system to produce time-lapse full disc animations,these will show solar flares in the context of full disc and theyare also very useful to capture associated shock waves[Moreton waves]. The images captured by the GONG networktelescopes also capture full disc images, each image is acomposite of two exposures one for the disc and another forthe prominences. This is the easiest way to get full discimages but it does not deliver high-resolution full disc

images.

If your goal is to achieve medium resolution full disc imagesthen you will need to take shots of the separate parts of theSun and then merge them together in a suitable programsuch as Photoshop to create the full disc. Most imagers that Iknow will merge 4 or 9 panels to create the full disc. Whentackling such a work it is essential to work fast as your targetis moving [through plasma flow] and with a long delay thefeatures will not match up across the different panels. If you

have never tackled a mosaic I would recommend that you initiallyexperiment on a static target that is about the same apparent sizeas the Sun, I am suggesting the Moon!

If like me your goal is to achieve a very high resolution full disc, thenlonger focal lengths are necessary and this reduces the field of view so farmore images are required to produce a full disc. The time element to process theselarger images is significantly longer as I have recently found out.

Making a mosaic

Download the latest image from the active GONG site as this will help you rotateyour camera to get the correct solar orientation before starting on your imagingrun.



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To produce a successful mosaic it is vital to make sure that as the telescope istraversed across the face of the Sun and carefully ensure that the whole disc iscovered with the photos taken. If an area is missed this is like trying completing a jigsaw only to find a piece missing! When I am making a mosaic I ensure that Ihave plenty of overlap with successive photos on all sides of the images. I normallystart at the left side of the top of the Sun and traverse right while shooting 500

frame video sets and then move down working to the left and so on.

The next stage is to process all the images to the same standard, this is fairly easyif the seeing is consistent and there are no thin cloud present but more difficult ifnot. I use Photoshop CS5 to construct my mosaics and I presently have noexperience of other programs but there are many that are suitable.

I start by opening a new document and initially select the International paperoption [a large size sheet]. I then default the background colour to black using twobrightness/contrast background masks and then I click on “layer” and “flatten

image”. I import the first photo and set it in position, I then select and import thesecond photo and use the “move tool” and make it 50% transparent in “layer” thisallows for fine positioning of one photo over the other [zoom in a few times tocheck for exact alignment]. Turn the layer back to 100% [fully on] and then selectthe eraser tool to merge the two together and remove any hard edges that show aclear indication that they are separate photos.

Some of my friends use this process to build ¼ of the image as separate pieces andthen at a later stage put the four quarters together to achieve full disc.

Once the full disc is fitted together it may still look patchy with areas of dark andlighter tones. This can be smoothed out by selecting the eraser tool again at a lowpercentage say 2% and gently work on the darker patches to blend them lighter sothat the image acquires a more even appearance. The colour layer can then beadded after this stage. When I add the colour to my photos and movies I alwaysuse the colour balance mask with three separate layers for shadows, mid tones andhighlight colours. I try to recreate an impression of the colours that I see in theeyepiece.

The photographic equipment available and the image processing techniques arecontinuously changing and improving as technology advances. I personally am notexpert in computing or advanced image processing techniques but I am alwaysexperimenting, willing to learn and also share my experiences and mistakes.Mistakes are a very valuable part of the learning process so just analyse what wentwrong and then find the solution.

The internet and particularly solar observing forums are an invaluable link to tapinto the experiences of lots of expert amateur solar images and everyone is wel-come to join in. I would recommend joining SolarChat and the solar section of theCloudy nights forum.

One expert solar imager Ken Crawford has posted an absolutely brilliant tutorial onsolar image processing in Photoshop CS5 here is the link. I would recommend you

http://solarchat.natca.net/index.php/en/forum/6-this-is-solarchat-/page-2

http://www.cloudynights.com/ubbthreads/postlist.php/Cat/0/Board/solar

http://www.imagingdeepsky.com/Tutorials/Solar_FullDisk.htm

http://www.imagingdeepsky.com/Tutorials/Solar_FullDisk.htm

http://www.cloudynights.com/ubbthreads/postlist.php/Cat/0/Board/solar

http://solarchat.natca.net/index.php/en/forum/6-this-is-solarchat-/page-2



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work through this tutorial a great way to get your desired result withoutreinventing the wheel.

Have fun with our Sun

Andy Devey

Photo 1: Here is my first attempt at ahigh resolution solar mosaic; itcomprises 40 separate photos takenat 1.6m focal length. At this stage Ihave merged the photos but notbalanced the tones to make it looklike a single image..

Photo 2 my first everlarge scale mosaic at-tempt: a photo of theMoon in Memory of NeilArmstrong

Photo 3: Here is myfirst attempt at a largescale high resolutionsolar mosaic achievedwith only very basicskill level in PhotoshopCS5 usage. There is 20hours work in this im-

age and I shall revisit itfrom time to time inthe future as my skilllevels increase.



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Photo 2



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Photo 3



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http://thesolarexplorer.net/



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http://thesolarexplorer.net/



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Not so many years ago it

was a common occurrence

that if you mentioned an

interest in astrobiology to

a gathering of scientists you’d be met with raised eyebrows, polite coughs, and sympathetic noises. The

science of ‘life in the universe’ has had a rocky path to follow.

There was good reason for skepticism. As much as people could agree that the fundamental questions of

astrobiology were incredibly interesting – tackling such tasty morsels as life beyond the Earth, life’s ori-

gins, and the cosmic significance of life – they could also agree that meaningful answers were a long way

off. A sample size of ‘one’ presents a steep challenge.

Times have changed though, and perhaps the most profound shift in this scientific endeavour has come

from the ‘astro’ part of astrobiology in the past couple of decades. Before the 1990’s professional astrono-

my had more than its fair share of planet-hunting corpses littering the landscape. As far back as in the late

1800’s, claims of planets in places like the 70 Ophiuchi system (a binary some 16.6 light years away)

were quickly refuted. In the 1960’s and 1970’s claims of planets around Barnard’s Star received a confus-ing mixture of support and devastating criticism from different sides of the astronomical community.

These efforts were pushing the boundaries of feasibility. Some relied on micrometre-level measurements

of stellar motion on photographic plates, a tricky enough thing made even more so by error sources such

as unreported equipment realignment and well-meant cleaning. It was not a happy situation.

By the 1980’s it was only a few very dedicated, and brave, professional astronomers who carried on, de-

veloping spectroscopic techniques for sensing the Doppler shift of light from stars that might be wobbling

around a common center of mass with unseen planetary companions. But believable detections of planets

were thin on the ground, and it was only in the 1990’s that a quick succession of discoveries began to

transform the field. First was the detection of planetary mass bodies around a pulsar, and close behind

came the first truly robust evidence of a giant planet tightly orbiting a sun-like star.

Flash forward nearly twenty years and we’re awash in planets. Close to a thousand confirmed worlds now

adorns the public listings, and my colleagues assure me that the database of NASA’s Kepler mission al-

most certainly contains 3,000 more bona fide objects awaiting the seal of approval. Extrapolating the sta-

tistics tells us that there must be billions of planets roughly the size of the Earth in our galaxy that are also

orbiting their parent stars at distances where a temperate surface environment could exist. In fact, some

analyses posit that a ‘habitable’ world ought to exist around one of the low-mass stars within about 16

light years of us, with a ninety-five percent statistical confidence.

This is one of the turning points for astrobiology, I think it could perhaps be the biggest. Now we actually

know that it’s reasonable to ask questions about life on other worlds because there are other worlds in

abundance, and some should be pretty close by. These provide tempting targets for the next generation of

telescopic instruments, from NASA’s budget-crippling- but-amazing JWST, to the new 30-metre class ob-

servatories that are slowly moving from drawing board to mountaintops.

JWST may be able to detect molecules like water and carbon dioxide in the atmosphere of a transiting

Earth-sized planet around a nearby low-mass star. The great ground based observatories may complement

this with an ability to spot oxygen. And all such instruments, together with observatories like the millime-

ter and sub-millimeter sleuthing ALMA, should reveal other properties of exoplanetary systems, such as

the presence of zodiacal dust and its progenitor asteroids and comets that may provide important clues to

the planetary environments.



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Much closer to home, astrobiology is helping pull together disparate fields of scientific inquiry. As the

Curiosity rover hauls its bulky science laboratory around the surface of Mars, it is scouring the dusty

terrain at the beck and call of geologists, geochemists, planetary scientists, atmospheric chemists, and

even biologists.

This rover’s ground truth, and the wealth of data from other rovers and missions – from Spirit and Op-

portunity to the Phoenix polar lander, and great orbital craft such as the Mars Reconnaissance Orbiterand Mars Express – is creating a picture of Mars that speaks to a rich, wet, history that could have been

more amenable to life. Right now there is also good evidence of seasonally varying water runoffs from

subsurface ice or aquifers, and for the presence of all the base elements for life. As of yet though there is

no smoking gun that points to living things on Mars; no complex organic molecules have been detected,

and there are conflicting measurements of atmospheric methane, a molecule that would be a potent sig-

nal of metabolic activity.

On the other hand, since the Viking missions of the 1970’s there have been no instruments on Martian

soil with the specific abilities to test for the presence of live organisms or their direct fossil presence. A

proposed NASA rover, Mars 2020, might change that, and might even prepare samples for eventual re-

turn to Earth.

Here, on the home planet, an array of new technol-

ogy and new thinking is being brought to bear on

scientific questions that reach out to some central

and profound aspects of the search for life. What

are life’s origins? How does life take over a plan-

et? How does complex life arise? How does the

human microbiome influence our evolution, and

how does the planet-wide microbiome influence

our entire environment?

These are tough topics, but our increasingly good

ability to manipulate the microscopic world of at-

oms and molecules, and our still growing compu-

tational capacity is making inroads. We’ve made

the first ‘artificial’ life (or at least cobbled together

a franken-organism of sorts), and chemists are

studying an array of possible routes that lead fromsimple molecules to the emergent complexity of

biochemistry. Also, although the modern Earth

may be a poor representative for Earth’s state

throughout its 4.5 billion year history, we’re get-

ting pretty good at unraveling the paleontological

and geophysical clues to its past, and the relation-

ship to life’s remarkable pathway.

But I think, again, that the most profound shift has

come from, and will continue to come from, our

newly found knowledge of worlds around other

suns. To put it quite simply; here finally is the op-

portunity to expand our sample size beyond a sin-

gle planet, and beyond a single planetary system.

That is a huge leap, which is already influencing

our thinking. Papers are now written that compare

our circumstances to those of other worlds, and

unlike such efforts in the past, we actually havereal data to go on. For example, a few months ago

Image: Mike Greenham



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the first simultaneous spectra were obtained of four planets orbiting the young star HR8799, one hundred

and twenty-nine light years from us. These are giant worlds, not yet the terrestrial-analogs we hope for,

but they present a truly alien picture that may be a portent of what is to come.

Spread across this system from about 14 astronomical units from their star to 68 (a distance equivalent to

the very outer limits of our Kuiper belt) they look like almost

nothing we’ve seen before. Each has a unique spectral finger- print, compounds like methane, acetylene, and carbon dioxide

swirling in their atmospheres. Only one of these planetary spec-

tra bears a slight resemblance to that from the night side of Sat-

urn, all the others have no solar system equivalent.

Glimpses like this are telling us that it’s a brave new galaxy out

there; and despite the inertia of science funding, and ill-

conceived political priorities across much of the world, very real

progress is being made. In fact, I think it’s fair to say that astro-

biology is starting to earn some long hoped for respect, and

that’s a good thing, because who hasn’t asked the very samequestions when gazing up at a night sky full of other suns?

Caleb Scharf Director of Astrobiology, Columbia University, New York. Author of the best selling book “Gravity’s Engines” and his new book “ The Copernicus Complex” out

Autumn 2014.

Image from:http://phl.upr.edu/press-releases/fivepotentialhabitableexoplanetsnow

http://phl.upr.edu/press-releases/fivepotentialhabitableexoplanetsnow







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What Is Lurking Around The Plough?

Some of you may have a telescope .Some may have a set of binoculars

sitting in a draw which need a dustingoff, or you may just wonder in awe atthe delights of a clear night sky. It iseasy to become overwhelmed with themillions of stars overhead, you may findit difficult to find an object in the sky. Soto give you your bearings starting thismonth we are going to have a look at

constellations to get your bearings.However to make it easier we are going

to take part of a constellation which iseasy to identify and find. This is called an ‘asterism’. This means a small formationof stars which is recognisable, but is partof a larger constellation.The image below left shows theconstellation Ursa Major or the GreatBear.

The Plough which is part of Ursa Majis part of the night sky which mostpeople find easy to find and pick outFinding the plough helps you find yo

bearings and you coordinates. The plough shape is quite distinctive in the sky andonce found you can find North or the pole star Polaris.

Ursa Major is a constellation which is in the night sky all year round. It appears torotate around the Pole Star Polaris.

Generally speaking the Plough is in a northerly direction. At this stage will imagineyou are standing in a circle and you are standing in the centre. We can divide thecircle into two halves, one we will call North and the other South.

The image to the left is an illustration, be it a simple one of finding north. Finding

North and the North Star (Polar Star, Polaris) is how we polar align our telescopes.This is really a brief and simple way of finding North and from here you can find



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other objects in the night sky. Howev-er these days many of you havesmartphones, tablets, laptops etc. Sodownloading software such a Stellari-um will help you navigate around the

sky.

( http://www.stellarium.org/ )

The image to the right is animage taken using theStellarium software.If you have a telescope orbinoculars then there are someinteresting objects to find andlook at. The Plough is in myopinion an area of the sky whichmany overlook, however with alittle patients you too can viewthe wonders of this region of thesky.

What to See! Here are some objects

Planetary Nebula: M97 Owl nebulaGalaxies: M51 (Whirlpool), M81,M82,M101,M108,M109Double Star M40Meteor Showers: Alpha Ursa Majorides, Ursiden, Leonider—UrsidenMultiple Stars: Mizor and Alcor

Words: Dave Bood

http://www.stellarium.org/





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Mike Greenham



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Coming in the next edition of the OASCast, Alastair Leith discusses the role of So-cial media and the internet in astronomy. How it

made communication and networking easier thanback in the day where people relied on snail mailand conferences mainly to keep up to date.He also takes the opportunity to look at how

online astronomy societies have evolved over the

years and the tools they use to collaborate, inte-

grate and keep in touch



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