What is Astrology?

Astrology is a pseudoscience that claims to divine information about human affairs and terrestrial events by studying the movements and relative positions of celestial objects. Astrology has been dated to at least the 2nd millennium BCE, and has its roots in calendrical systems used to predict seasonal shifts and to interpret celestial cycles as signs of divine communications. 

Many cultures have attached importance to astronomical events, and some—such as the Hindus, Chinese, and the Maya—developed elaborate systems for predicting terrestrial events from celestial observations. Western astrology, one of the oldest astrological systems still in use, can trace its roots to 19th-17th century BCE Mesopotamia, from where it spread to Ancient Greece, Rome, the Arab world and eventually Central and Western Europe. Contemporary Western astrology is often associated with systems of horoscopes that purport to explain aspects of a person's personality and predict significant events in their lives based on the positions of celestial objects; the majority of professional astrologers rely on such systems.

Throughout most of its history, astrology was considered a scholarly tradition and was common in academic circles, often in close relation with astronomy, alchemy, meteorology, and medicine. It was present in political circles and is mentioned in various works of literature, from Dante Alighieri and Geoffrey Chaucer to William Shakespeare, Lope de Vega, and Calderón de la Barca. 

Following the end of the 19th century and the wide-scale adoption of the scientific method, researchers have successfully challenged astrology on both theoretical and experimental grounds, and have shown it to have no scientific validity or explanatory power. Astrology thus lost its academic and theoretical standing, and common belief in it has largely declined. While polls have demonstrated that approximately one quarter of American, British, and Canadian people say they continue to believe that star- and planet-positions affect their lives, astrology is now recognised as a pseudoscience - a belief which its advocates incorrectly present as scientific.

My blog is about Astronomy, not Astrology.

What is Astronomy?

Astronomy (from Greek: ἀστρονομία) is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates outside Earth's atmosphere. Cosmology is a branch of astronomy which studies the Universe as a whole.

Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Nowadays, professional astronomy is often said to be the same as astrophysics.

Professional astronomy is split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects. This data is then analyzed using basic principles of physics. Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. These two fields complement each other. Theoretical astronomy seeks to explain observational results and observations are used to confirm theoretical results.

Amateurs play an active role in astronomy. It is one of the few sciences in which this is the case. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets.

What is a Galaxy?

A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek galaxias (γαλαξίας), literally "milky", a reference to the Milky Way. Galaxies range in size from dwarfs with just a few hundred million stars to giants with one hundred trillion stars, each orbiting its galaxy's centre of mass.

Galaxies are categorised according to their visual morphology as elliptical, spiral, or irregular. Many galaxies are thought to have supermassive black holes at their centres. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun. As of March 2016, GN-z11 is the oldest and most distant observed galaxy with a co-moving distance of 32 billion light-years from Earth, and observed as it existed just 400 million years after the Big Bang.

Research released in 2016 revised the number of galaxies in the observable universe from a previous estimate of 200 billion to a suggested two trillion or more and there are more stars in the universe than all the grains of sand on planet Earth.

Most of the galaxies are 1,000 to 100,000 parsecs in diameter (approximately 3,000 to 300,000 light years) and separated by distances on the order of millions of parsecs (or megaparsecs). For comparison, the Milky Way has a diameter of at least 30,000 parsecs (100,000 ly) and is separated from the Andromeda Galaxy, its nearest large neighbour, by 780,000 parsecs (2.5 million ly.)

The space between galaxies is filled with a tenuous gas (the intergalactic medium) having an average density of less than one atom per cubic meter. The majority of galaxies are gravitationally organized into groups, clusters, and superclusters. The Milky Way is part of the Local Group, which is dominated by it and the Andromeda Galaxy and is part of the Virgo Supercluster. At the largest scale, these associations are generally arranged into sheets and filaments surrounded by immense voids. Both the Local Group and the Virgo Supercluster are contained in a much larger cosmic structure named Laniakea.

Return to Bowland

On Tuesday I went out for the first time in four months to look for the Milky Way. With it only just being past the summer solstice it wasn't the best time I know, but I was I was wondering how dark it got in our usual spot in the Forest of Bowland. The answer is, not very - certainly not dark enough to see the Milky Way properly, although the murky high level clouds didn't help. No noctilucent clouds either, which was another thing I was hoping for.

As my broken tracking mount has still not been returned, I could only take a wide angle set up with me to do some constellation shots.

So I didn't come back with much except for a few shots like this one showing Cassiopeia and Andromeda - can you see it? The best thing was meeting up with John and Susan Walsh and having a chat at an appropriate distance.

A very small and faint Andromeda is ringed in the above photo.

Jupiter and Saturn over Pendle Hill, looking south from Bowland. It wasn't this light, but the camera can make it seem brighter. And that's no sunset, it's the light pollution from Clitheroe. A bit over-sharpened I'm afraid.

So not many photos to process for once, but here's a couple of annotated asterisms to finish with:

Astronomy and Space Sessions for Primary Schools

Attention all primary school teachers, governors, youth workers and anyone connected to primary schools or youth groups. I'm looking to offer astronomy sessions to schools.

I'm a former secondary school Computing and IT teacher who took early retirement from being Head of Faculty a few years ago. I did some IT support work for a while before going on to work one day a week for four years in a primary school where I taught the basics of computer programming to Years 3-6.

In addition, for the last six years or so I've coordinated a team of five volunteers who visit primary schools and youth groups giving free presentations about birds, wildlife and nature as part of Leigh Ornithological Society's education programme in the Wigan and Leigh area. This team were instrumental in helping the Society receive the Queen's Award for Voluntary Service in June 2020.

But now I'm looking to branch out and hopefully earn a bit of pocket money to help fund my astrophotography habit. So I'm looking to offer primary schools a two hour afternoon (paid) session about astronomy, the solar system and space topics in general. The session would include a presentation with high quality information slides and photographs, demonstrations, a practical activity, quizzes and worksheets all in line with National Curriculum topics. The exact content can be tailored to individual schools.

So if you are a primary school teacher, governor or have some other connection with a school or youth group who you think would be interested in this sort of session, please get in touch via an email to jones_mp@yahoo.com.

Obviously, these sessions will only be able to take place when we are back to normal after the current Coronavirus situation has passed. But that will give me some time to prepare the materials!

I'm Not Phased By These Moonshots

My first attempt at showing a sequence of moon phases for the end of May 2020.

Far from perfect as it was a bit of an afterthought really. I'd need to set up more consistently each night to improve the quality. But I'm sure that sooner or later, everyone wants to try to do something like this.

Strawberry Moon in June 2020

The best I could do with last night's 'Strawberry Moon' (5/6/20).
Too cloudy and dull all night and this shot was taken through thin cloud.

It's called a Strawberry Moon because it coincides with when strawberries were originally harvested. Less common nicknames for this month's full moon, based on old European naming traditions, are the Mead Moon, Honey Moon, and Rose Moon.

Reprocessed Sunspot AR 2765

Sunspot AR 2765 - (13:24pm 5/6/20)

Reprocessed to enhance the faculae or bright areas near the actual sunspot.

Sunspots are temporary phenomena on the Sun's photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Sunspots usually appear in pairs of opposite magnetic polarity. The Sun's magnetic field wells up to the photosphere which is the Sun's visible "surface". The powerful magnetic fields around sunspots produce active regions (AR) on the Sun, which often lead to solar flares and Coronal Mass Ejections (CMEs).

You Never Forget Your First Sunspot

Wow! I've just taken my first ever photo of a sunspot! Thanks to Anthony Wallace Cross from the Manchester Astronomical Society for the heads up.

AR 2765 (Lower left side)

A closer view:

WARNING: DO NOT LOOK DIRECTLY AT THE SUN THROUGH A CAMERA VIEWFINDER, BINOCULARS OR A TELESCOPE. ALWAYS USE A SPECIAL SOLAR FILTER AND CHECK THAT IT IS NOT DAMAGED.

Fame at Last! - I'm in the Manchester Evening News!

*** Warning - A Work in Progress ****

Everything in this blog is still a work in progress as I try to backtrack to last Autumn when I started to take my journey into Astrophotography and Astronomy more seriously.  I'll be backdating some of the posts so that they appear in the correct chronological order and sequence.

The aim of this blog is to put some more detailed information about what I do and how I do it as I climb the steep learning curve that us astrophotography.  Hope fully some of the information here will be useful to others as they start their journey too.  I'll be including links to other internet-based resources which I've found useful or interesting.

So please bear with me whilst I write the posts and upload the photos and I'll remove this message once the site is fit to be viewed :) Once that is done it will be updated as I do each new set of shots.

Thanks for reading.

Martyn (GeekTeacher Astro)

Shooting For The Moon

Recently I've had a few people asking about the camera settings for photographing the moon in a single shot. As cameras have different features, I can only tell you what I use and what works for me on my Nikon D500 DSLR, but it will give you something to aim at - here goes:

1. Use a tripod if at all possible
2. Use a shutter release cable if possible, if not use the self-timer set to at least 3 seconds
3. Also set the shutter delay to 3 seconds if possible
4. Put the camera in full manual mode
5. Turn off autofocus and image stabilisation on the lens
6. Choose single point or centre-weighted metering
7. Set the ISO to 100
8. Set the aperture to f/11 (Looney 11 rule)
9. Use 'Live View' on the back of the camera to zoom in on a crater or the edge of the moon to get the best focus position
10. Focus manually by turning the lens focus ring back and forth until the image is sharp
11. Adjust the shutter speed until the exposure looks right starting at about 1/125th second
12. Press the shutter release button to take the shot.

It is possible to use autofocus with the moon, but it's sheer brightness and clouds can cause it to try to refocus, so I usually avoid it. The best moon shots are usually taken either side of the full moon, or in the waxing and waning gibbous and crescent phases, when a bit of shadow and the sun's position help to bring out the surface details. Photos taken of the full moon tend to look very flat with the direct sunlight hitting the surface.

Hope that helps.

Waxing Gibbous Moon, Again! (4/5/20)

Here's a shot of last night's waxing gibbous moon, but with a difference. I've tried using PIPP to convert a short video of the moon into separate TIF files which can then be stacked in AutoStakkert3, but without much success.  I seem to get much better results from single shots only processed in Photoshop. This image is a stack of eight separate shots blended together using only Photoshop.   However I must admit that this one looks a tad sharper than the single shot shown below it, although it has gained a bit of a purple tinge, which I can remove if necessary.

Below is just one of the single shots used to make the above image:

The stacking process I used in Photoshop was as follows:

1. Choose File>Scripts>Load Files into Stack
2. Click Browse and select all the files you want to stack together
3. Tick the 'Attempt to Automatically Align Source Images' checkbox and then OK
4. Then in Photoshop, select all the layers
5. Choose the 'Lighten' blend mode.
6. Process further if required and then save.

Craters on the Moon

Today I used Wikipedia to compile a list of crater photos in order to learn some more of their names.

A Closer View

Last night was a bit of an experiment. I had planned to do some Deep Sky imaging (galaxies, nebulae and star clusters) but because the clouds rolled in, I ended up only doing a few moon shots. I wanted to try using my QHY5P-IIC guide scope camera on my Skywatcher 200P telescope for getting some closer views of the moon. This camera also has a use as a planetary camera. I got all this stuff in a secondhand bundle with my mount last October and haven't used it until now. Little did I know how difficult it was going to be.

First of all I didn't bother with tracking as I couldn't see Polaris to do my polar alignment. Instead I just moved my equatorial (tracking) mount manually as a tripod. At such high magnifications it was so hard to even find the moon as I wasn't sure about where the focus was or even if I had the right number of extension tubes necessary to be able to focus this camera on my telescope.



I captured these images in SharpCap which also has to be used to focus the camera as, a bit like a webcam, it has no screen. Focusing caused the scope to wobble and so I had to turn the wheel a bit and then wait while it settled before making another small adjustment - very hit and miss.

 

But in the end I managed to get these two videos of the moon moving past my scope. Focusing probably could have been sharper and I didn't bother to alter any image quality or colour settings in SharpCap, which is something I'll look into next time.

Y.A.M.S.

Y.A.M.S. stands for Yet Another Moon Shot.  I often take shots of the moon when other plans have gone by the wayside. It's always a good fallback. Tonight I had planned to do a full evening of Deep Sky Object (DSO) shots because this afternoon the weather looked to be set fair for a while. But things don't always go to plan, do they?

The moon appeared early in the afternoon as a very faint object in the sunny blue sky, so I really had to ramp up the contrast and brightness to get anything worth looking at. I suspect you will either love or hate this image of the daytime moon.

Afternoon Moon (2/5/20)

After it had gone dark I started taking a few shots with my big telescope (which I am still getting used to) and the guide camera which can also be used as a planetary camera. I was pleased to have some success with this as the guide camera produces much closer images than my normal cameras do. I waited for Polaris to appear out of the clouds that had rolled in so that I could polar align my mount and get on with tonight's main business.

I waited, and waited and ... waited, but the clouds didn't lift. So I just kept taking a few more moon shots in the hope that it would lift eventually. By 11pm it had got colder and damper and there was dew beginning to form on the grass, so I decided that would be it for the night.  Of course, after I had packed everything away, the sky started to clear again, but by then I'd had enough and I decided that I just process what I'd got and call it a night.  Here's the first of them and more will follow tomorrow.

Waxing Gibbous Moon (2/5/20)

Tonight's Moon (1/5/20)

Tonight's waxing gibbous moon with various processing methods applied. Can you see any real difference - which do you prefer?

I wondered that if I cropped the shots into two halves, would the detail be clearer in each section?

I also thought it might be a good idea to dig out this old moon map I made a few months ago:

What is a Light-Year?

The distances to our nearest stars, galaxies and nebulae are huge - astronomical even!  If we used our normal units of measurement such as kilometres or miles, the number of digits would be huge too. So to make the numbers easier to handle, the concept of the light-year is used.

In 1838, the German astronomer Friedrich Wilhelm Bessel was the first to use the light-year as a unit of measurement in astronomy. He measured the distance to the binary star 61 Cygni as 10.3 light-years.

The light-year is not a unit of time although it sounds like it might be - it's a unit of length or distance, just like kilometres and miles. As defined by the International Astronomical Union, a light-year is:

'the distance that light travels in a vacuum in one year'

The light-year measures about 9.46 trillion kilometres or 5.88 trillion miles.  If these numbers were written using our normal units of length, that would be 946,000,000,000,000 kilometres or 588,000,000,000,000 miles.

I think you can see now why we use light-years rather than kilometres or miles! But even though the term is still very much in use, another larger unit the parsec (which is equal to 3.26 light-years) is actually much more popular in the scientific community.

Here are some approximate distances to some of the better-known night sky objects:

Deep Sky Objects:

• Andromeda Galaxy - 2.537 million light-years 
• Orion Nebula - 1,344 light-years 
• Betelgeuse - 642.5 light-years 
• Polaris - 433 light-years
• Capella - 42.92 light-years
• Arcturus - 36.66 light-years 
• Vega - 25.05 light-years 
• Sirius - 8.61 light-years 

Our Solar System:

• Sun - 150 million kilometres (93,000,000 miles) 
• Mercury - 77 million kilometres (48 million miles ) 
• Venus - 40 million kilometres (25 million miles) 
• Moon - 384,400 km (238,900 miles)
• Mars - 225 million kilometres (140 million miles)
• Jupiter -  778 million kilometres (484 million miles)
• Saturn - 1.44 billion km (894 million miles)
Uranus - 2.75 billion km (1.71 billion miles)
• Neptune - 4.5 billion kilometres (2.8 billion miles)

Note: all the distances to the planets in our solar system are approximate averages as they vary with orbits. The picture above does not show these distances to scale, although the relative planet sizes are correct.

Tonight's Moon - 29/4/20

Tonight's single shot of the moon (29/4/20). I've decided that most of my previous moonshots have been taken using the wrong white balance. I can reprocess them to correct this, but I don't think I'll bother - there'll be plenty more moons in the sky!

Venus is a lot harder to photograph my camera gear.  It's very bright, very small and a long way away. Here's the best I can currently do. At least, being a crescent shape, it shows it has phases like the moon.  Only Mercury, Venus and the Moon show full phases like this, because they are between the Earth and the Sun.  Mars shows some partial phases I believe.

Getting Started With StarGazing

If you want to get started in StarGazing I'd recommend getting a pair of binoculars and a book such as the one in the Amazon link below. I'd say that you need to pay at least £50-£60 for a decent pair of binoculars as cheap ones often disappoint and may not be aligned correctly. Good budget brands include Opticron, Celestron, Hawke and Helios as well as the range supplied by the RSPB bird society which I think may be rebranded Viking products.

I'm not making any recommendations except to say have a look at the websites shown below and consider visiting Focal Point Optics in Cheshire who will let you try out various models, give you great advice and not put you under any pressure to buy.

• BBC Sky at Night Magazine https://www.skyatnightmagazine.com/reviews/binoculars/
• Focal Point Optics - https://www.focalpointopticsltd.com
• Book - https://www.amazon.co.uk/gp/product/000825771X…