A helping hand for oceanographers

Whilst exploring Google Scholar, I came across an interesting article that used a rather different approach to oceanographic observation: elephant seals.

Screen Shot 2016-03-06 at 21.08.10Living in herds in the Southern Ocean, these three tonne tanks seem a strange choice when it comes to measuring various oceanic properties, but are surprisingly efficient. By attaching conductivity-temperature-depth sensors (or CTDs) onto the heads of elephant seals, these mammals act as a biological platform from which measurements can be made. In fact, elephant seals are well suited to this job: they dive very deep and are able to swim long distances, likely visiting a wide proportion of the Southern Ocean. In a study by Xing et al (2012), 15 elephant seals were tagged in the region surrounding the Kerguelen Islands – an archipelgelo that lies on the boundary of the Antarctic tectonic plate. This equated to 1894 profiles being collected in just over a year, and emphasises the potential of utilising animals in this way.  As it happens, the use of animals in scientific research is a growing field, and is known as biologging.

Biologging has only become possible relatively recently and is used primarily to monitor animal behaviour e.g. foraging, migration and even environmental assessment – such as the impact of offshore wind farms on seabirds. However, over the last 15 years, the development of Satellite Relay Loggers (that is, the combination of satellite relay – essentially fancy GPS) and CTD sensors has allowed a collaboration between biologists and physical oceanographers, expanding our observational capabilities of the ocean.

One of the main problems with observational oceanography is the sampling resolution: there are enormous parts of the ocean that remain a sampling mystery. This is due primarily to the fact that the sensors we use are very small and the ocean is very big, so only a limited proportion of the ocean can be measured at any one time. Combined with the fact that research ships are expensive to run, this leads to some parts of the global ocean that are very well-known to us (such as the easily accessible coastal regions) and areas that haven’t seen any CTD sensor in over ten years, if ever!

One of the ways to combat this problem is through the introduction of autonomous underwater vehicles (AUVs) – essentially robotic sensors. These robots are quite happy to go up, down, backwards and forwards, measuring the water column as they go for however long their lithium batteries last, and have drastically increased both the spatial and temporal resolution of observational oceanography.

However, they aren’t perfect, and there are still vast regions of the ocean where these robots can’t reach. Outside of 60°N-60°S latitudinal range, the presence of sea ice is a problem. When I was an undergraduate, we were told a story of a multimillion pound AUV that became lost beneath the Arctic sea ice. I have yet to know if it was ever recovered, but global warming might lead to some interesting robotic discoveries if the ice caps continue to melt.

New technological advances with AUVs are being made constantly, so it is highly possible that these type of limitations may not be permanent. In the meantime, however, biologging may be a useful and reliable alternative, particularly as elephant seals don’t need batteries and their thick skin is not prone to water leakage.

That being said, biologging does come with its own unique difficulties, the animal must be sedated for the sensor to be attached, and once again for its removal – a dangerous and sometimes laborious task. It also has to be noted that the animal’s welfare is a top priority for these researchers, and every effort is taken to ensure the animal is by no means distressed throughout the biologging process.

Nevertheless, biologging provides a useful tool to measure those hard to reach places where humans and robots dare not tread.

Post By: Jenny Jardine

References:

Charrassin, J B., and others, (2010), Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: potential synergies with ocean color remote sensing, IN J. Hall, D. E. Harrison and D. Stammer (Eds.), Proceedings of OceanObs 09: Sustained ocean observations and information for society (Vol. 2), Venice Italy, September 2009. ESA Publication WPP-306

Roquet, F., and others, (2011), Validation of hydrographic data obtained from animal-bourne satellite-relay data loggers, Journal of Atmospheric and Oceanic Technology, 28, 787-801

Xing, X., and others, (2012) Quenching correction for in vivo chlorophyll fluorescence acquired by autonomous platforms: A case study with instrumented elephant seals in the Kerguelen region (Southern Ocean), Limnology and Oceanography: Methods, 10, 483-495

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The neuroscience of politics: what your brain says about your vote

So it’s super Tuesday. For anyone reading this in the US you’ll know that this is a pretty big deal in the presidential primary season but, to humour us Brits, here is a brief overview of what it all means.

800px-2008_Wash_State_Democratic_Caucus_03Super Tuesday is the day (or days) when the greatest number of states hold their primary elections, narrowing the field of candidates vying for power in the upcoming general election. The day is thought to ‘throw candidates in at the deep end’ giving them a taste of the trials and tribulation of running a national campaign. Results from Super Tuesday (which are expected to start flooding in soon after polls close at 19:00/20:00 EST, 00:00/01:00 GMT) will give a good indication of the direction of these campaigns – creating a sink or swim moment for candidates.

With heightened political fervour gripping the nation, we at the Brain Bank want to explore the role the brain plays in the way we vote:

One major question scientists have been researching is whether it is possible to predict our political leanings (conservative vs liberal or republican vs democrat) by delving into the structure of our brains. Although this question may seem pretty far fetched, a number of studies have in fact found links between the size and activity of certain brain structures and a subjects political beliefs. Specifically, these studies reliably show that liberals tend to have a larger and more active anterior cingulate cortex (ACC) while conservatives are more likely to show an enlarged amygdala.

Now, before we delve into more detail on the functions of these brain regions and how they could be linked with conservative or liberal thinking, we need to be clear on a few points. Firstly, even though a number of studies converge on the same findings, these do not represent a large enough sample size to say that this will hold true for all individuals. We also have no way of disentangling cause and effect in these studies, so we can’t say whether your brain drives your political views or whether it is your views which shape your brain – although this would be a very interesting question to ask!

So, with this in mind lets explore what these brain regions do and how their functions may be linked to political beliefs.

7488934812_d8bee1e2b0_qThe ACC is involved in cognitive control, conflict monitoring and emotion regulation. The ACC is basically the brain’s equivalent of a focused micromanaging boss. It helps us sort through incoming information and choose which bits are relevant and which are not. It also works to regulate our emotions, keeping them in check so they don’t get in the way of logical thinking. Those with the ability to maintain low emotional arousal alongside high cognitive control may be better at handling conflict, more adaptable and have high cognitive flexibility.

But what about the amygdala?

The amygdala is heavily involved in the formation of emotional memories and a process known as fear conditioning. People with larger amygdala may be more likely to show empathy and could be swayed heavily by emotive arguments. However, heightened emotions may also lead to less logical decision making, hinging choices on emotion rather than logic.

These findings could be used to argue that liberals may be more comfortable with complexity, more flexible in their thinking and more willing to incorporate new information into their current belief system. On the other hand, conservatives could be more likely to allow their beliefs to be coloured by emotion. This may make conservatives less comfortable with change, finding that stability causes them less anxiety. Interestingly, it has been suggested that conservative thinking hinges more on the stability of previously held values (think gay marriage) while liberals are thought to be more accepting of change and more willing to shift their world views based on new evidence.

66245374_afe6d3d8d1_qThis data is certainly interesting, however it is not helpful to view this as a strict dichotomy, or indeed something which remains rigid throughout the course of an individuals life. I wrote an article a few years back discussing plasticity in the brain. We know that every experience we have is capable of altering the structure of our brains at both a cellular and network level. Therefore, it makes sense that something as nuanced as political belief would undoubtedly be shaped and modified over the course of our lives by our experiences.

We know that, at least in Britain, age (and associated experience?) is a strong predictor of political affiliation, with liberalism associated with youth and conservative ideals with advancing age. Indeed it was once said that “Any man who is under 30, and is not a liberal, has no heart; and any man who is over 30, and is not a conservative, has no brains”. It has been suggested that as individuals settle down, find secure jobs and start families they crave stability, are more anxious of change and therefore more likely to vote conservative. It is possible that these changes are based on incremental alterations in brain structure, perhaps brought about by lifestyle changes.

Personally, my voting style altered when I came to university to study a scientific subject. Before university I tended to base my vote on the beliefs of my parents and peers, whereas now I try to weigh up as much evidence about the candidates as I can find before making a decision. I generally lean to the left, but could (and have) been swayed by policies on both sides. I like to think I would be an outlier in these ‘brain structure’ studies, alongside many other moderate (middle ground) voters.

It seems clear that differences do exist in the thinking style of both parties and I am inclined to believe that this may be reflected in the brain structures of strong supporters on both sides. However, there is undoubtedly room for further research into this topic, including questions such as: what defines a moderate voter? Does brain structure change with political affiliation? and does brain structure alter with age?

What are your views? we’d love to hear your experiences in the comments below.

To learn more visit National Geographic

Brain Games:  Life of the Brain premieres Sunday, March 6, at 9/8c on National Geographic Channel.

Post by: Dr Sarah Fox

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Charity at home and abroad

I am a Spanish scientist. I came to Manchester in 2007 to work as a postdoc in the Paterson Institute for Cancer Research. I have been working in oncology for the last 5 years so here I will focus on this, although what I’m about to speak about could also be extrapolated to many other causes.

image3It has always amazed me how committed people in this country are to fighting cancer. How so many adopt this fight as part of their daily lives; you see charity boxes in so many places (pubs, shops, coffee shops), people run, cycle, climb and swim all to raise money for cancer research. It seems so easy and so rewarding; to the point that it actually seems weird if you don’t get involved in something!

This leads me to question why this does not happen in my country? Is it because we are less supportive, are we so money orientated that we can’t give a penny for these causes or is it that that the Mediterranean diet protect us from cancer so much so that we don’t care or worry as much? Well, not the last one, of all EU countries Spain has the third highest rate of deaths due to cancer in people under 65. But what about the other two? Let’s think about them: are we Spanish people less supportive? I would say no. Spain is the world leader in organ donation and transplantation, which is pretty impressive since we are not a very big country. Not only that but we always show our support in the face of global image1catastrophe, organising call-in TV shows where people give money and which often raise many millions for the cause. So how about the second reason, are we a little bit tight with our money? As I said before, we are not. We as a country are happy to donate whenever we think people need it. We even broadcast TV shows where people can talk about their financial problems and others just call-in and donate money to them,offer them jobs or even give them a local rent free to start up a new business. So why is Cancer Research UK  so much more successful than it’s Spanish counterpart (CRUK raised 661 million pounds in 2014 while it’s Spanish equivalent reached just 44 million)?

There could be several explanations for this. Firstly, when people donate organs their action will have a tangible effect on someone desperate for that organ, it will save a life right away. The same is true for donations made towards global catastrophes, when people donate money to these causes they believe that their money will go to help those whose image2lives have been damaged. But when they donate to cancer research they don’t see any instant benefit, people think it is a waste! Spain is not a leading country in cancer research so why are they going to donate to this cause? However, if people don’t get more involved we are never going to be a leading country. We have no charity shops and barely any money boxes dedicated to this cause. There are very few races organised with very little dissemination in the media. Among my academic friends working in Spain only one was even aware or the existence of World Cancer Day on the 4th of February.

I believe that if more people were to get involved this would encourage many others to do the same. Therefore, making advances in cancer research more likely and showing people a tangible outcome to their charitable donations. It just requires some compromise and support from different institutions and news industry. I hope that in the future this changes because not much has been changed in the last 9 years.

Post by: Cristina Ferreras

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Making Metals (More) Interesting

Metals are boring. Sure, they’re nice and shiny. And they’re definitely useful. But could you honestly, hand on your heart, say that the last time you saw a bit of metal you jumped for joy? Probably not.

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Metals: a bit boring?

The trouble is, we’ve been playing around with chunks of metal for so long that the novelty has worn off. You can melt down metal and create swords, axes and other cool things. That’s pretty neat, but it’s not exactly cutting-edge technology (see what I did there?). You can melt metals and mix then up to get alloys, which are awesome for jazz bands (brass instruments) and eating (stainless steel) among many other uses. Don’t get me wrong, I’m a great stickler for jazz and a big fan of the classic knife and fork combo, but neither of those things are particularly new.

Worse still, as a physicist working in the realm of optics whose job is to find things, shine light on them and see what happens, I find chunks of metal truly boring.

Fortunately for us optical physicists, lots of researchers in other fields were having a similar problem and suggested a solution: make things really really small and try measuring them again. The beauty of nanoscience is that conventionally boring materials can be made interesting again by studying them on the nanoscale (billionths of a metre). A recent example of this approach can be found in the world of carbon. Graphite is a pretty boring form of layered carbon atoms (as found in pencils), but reducing a piece of graphite down to a single layer (graphene) makes weird stuff happen.

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Metal nanoparticles in stained glass windows: quite a bit more interesting.

What happens, then, when we shine light on tiny pieces of metal? It turns out we’ve had the answer right before our eyes for centuries without even knowing it. The brilliant colours we see in stained glass windows are caused by pieces of gold or silver a few tens of nanometres across. These pieces of metal absorb extra wavelengths of light which they wouldn’t absorb if they were of a more “conventional” size. Change the size of these metal nanoparticle by a few dozen nanometres (say, from 80 nm down to 50 nm) and the wavelengths of light they absorbed (and so the colour of the glass they are dispersed in) changes. This is all a bit weird, isn’t it? Compare a gold ring with a bar of gold, or a gold statue, and they all look to be the same colour – even though we’ve gone from something a few millimetres in length to something on the order of a metre. Yet change the size of a nanoparticle by a mere 10 or 20% and we get an enormous change.

So, what’s going on?

It all comes down to everybody’s favourite subatomic particle, the electron. Metals are made of regularly arranged atoms, this arrangement leaves one of the electrons (or more, depending on the metal) from each atom free to wander around the atomic lattice more or less as they feel. These delocalised electrons can be made to move in an ordered way by giving them energy. For example, by applying a voltage across a long, thin piece of metal (commonly known as a “wire”) the delocalised electrons will all flow along the metal in the same direction – this is electricity. But attaching crocodile clips to metallic nanoparticles is, as you can probably imagine, rather tricky. Instead we can induce collective motion in a nanoparticle’s delocalised electrons by shining light at it. In a nanoparticle, the delocalised electrons are confined to a small region, and they will strongly absorb certain wavelengths of light and convert this energy into collective oscillations. These light-induced electron oscillations are known as plasmons. The wavelength of light which excites these plasmons depends on the size of the particle but also on their shape and electron density (which in turn depends on the metal used).

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The principle of plasmon resonances in metallic nanoparticles.

The fun doesn’t stop with stained glass windows, either. Tuning the properties of metal nanoparticles, placing them in arrays and combining them with other materials allows for all kinds of weird and wonderful properties with potential applications in biosensing, optoelectronics, cancer therapy, and possibly even invisibility cloaks (each of which will be discussed in subsequent blog posts). Best of all for a generation of bored metal-optics researchers, this cocktail of weird results means that metals have once again become interesting and will likely remain interesting for some time.

Post by: Philip Thomas

 

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Webcam astronomy: simple but effective

Over the past 4 years, I have been steadily assembling equipment for the purpose of photographing deep sky objects (DSOs). These are dim, sometimes large, diffuse cloudy patches when viewed using binoculars or a small telescope. Starting with the Andromeda galaxy (see below), I used a simple, long tube telescope fitted to a tracking mount (that tracks the DSO as it moves across the night sky). This allows a camera to collect light over a long period of time (often up to several hours) showing features that would otherwise be far too dim to detect with the naked eye.

The Andromeda galaxy (M31) taken by collecting over 2 hours of photographic exposures.

The Andromeda galaxy (M31) taken by collecting over 2 hours of photographic exposures.

Although I personally find this type of astrophotography very rewarding, there are some major drawbacks. The first and most severe is how sensitive this type of photography is to unwanted light. Since photographing DSOs requires a really long exposure, any stray light from streetlights or the Moon simply washes out the object’s detail. The second is the sheer time it takes to collect the light to produce these types of photographs. The main issue is that as I take these long exposures (typically I take over 30 shots each lasting up to 5 minutes), any disturbance such as a gust of wind or nearby movement can cause the image to smear.

Mainly for these two reasons, I decided recently to branch into a different type of astrophotography – webcam astrophotography. Although I don’t have any pictures to show yet (I haven’t finished modifying the webcam yet, but watch this space!) I will briefly discuss the principles of this form of astrophotography and how it can be achieved with very limited equipment (and budget).

Put simply, webcam astrophotography involves taking a video of a bright night sky object (such as a planet or the Moon) and using the best frames of that video to produce a high quality image. There are several advantages to this approach. Firstly, since the object you are photographing will be bright, the exposures are short. This means that movement of the telescope will not cause image smear. In addition, the telescope mount does not have to track the night sky very accurately since each frame of the video is taken over a fraction of a second (normally 1/30s). Secondly, bright objects far outshine artificial light pollution, which makes this form of astrophotography very suitable for people living in towns and cities.

image2

Photo of a bird with strong chromatic aberration caused by improperly focused violet light.

So, with a webcam and a cheap telescope mount, some impressive   astrophotography can be achieved (see this link). However, I have neglected to mention anything about the telescope. When photographing bright objects overcoming chromatic aberration (CA) is a real problem. This optical aberration occurs when light being focused through a lens splits into its constituent colours and these colours focus at different points. The colour fringing effect caused by CA is shown on the right.

So, I decided t20160130_093248o use a telescope design known as a Maksutov-Cassegrain (modelled by my lovely fiancée Sarah) that avoids CA through an ingenious use of lenses and mirrors. There are three important advantages of using this telescope. (1) The light entering the telescope does not split into different colours (as mentioned). (2) Light is also neatly folded up so the actual telescope is conveniently small. Finally, although the telescope is short, it is capable of imaging at high magnification – an important feature if you wish to image small Moon craters or the great red spot on Jupiter.

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A excellent image of Jupiter taken using a Maksutov-Cassegrain telescope and a cheap webcam. Photo credit: Dion from the Astronomy Shed.

In hindsight, perhaps I should have started my astrophotography hobby with webcam imaging; I would have saved a lot of time and money and not developed an irrational hatred of streetlights or the Moon!

Post by: Daniel Elijah

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The science behind the headlines: How Chemotherapy could change the lives of thousands suffering from MS.

MS is one of the most common neurological disorder affecting young adults in the western hemisphere, indeed the list of sufferers include a number of high profile names.

oligo-253x300Although scientists are still unsure of exactly what causes the disorder, they do have a good working understanding of disease progression. Symptoms stem from damage to a fatty covering which surrounds nerve cells, known as a myelin sheath. It is this myelin which allows neurons to communicate quickly with one another through a process known as saltatory conduction. In brief, cells called oligodendrocytes (in the central nervous system) and Schwann cells (in the peripheral nervous system) reach out branching protrusions which wrap around segments of surrounding neuron forming a sheath (see image to the left). Signals traveling through myelinated neurons are able to move rapidly by ‘jumping’ between gaps in this sheathing known as nodes of Ranvier. In the case of MS, damage to this sheath causes signalling between neurons to slow down, leading to a range of symptoms.

It is believed that, in the earliest stages of the disease, the body’s own immune cells (cells usually primed to seek out and destroy foreign agents within the body, such as viruses and parasites) mistake endogenous myelin for a foreign body and launch an attack.

Most current treatments focus on suppressing these immunological attacks by inhibiting the patients aberrant immune response. However, this novel and arguably ‘brutal’ new treatment focuses on destroying the patients existing immune system before re-building it again from scratch.

To understand how this treatment works, it is first necessary to give a bit of background into the immune system. Specialised immune cells, designed to protect our body from disease, are generated in our bone marrow. It is these cells which ‘misbehave’ in autoimmune diseases such as MS and can launch an attack our own cells. Key to this process is the existence of hematopoietic stem cells (HSCs) within the marrow. These cells are precursors to all other blood cells (including immune cells) and, given the correct environment, can develop into any other blood cell (see image below).
1024px-Hematopoiesis_simple.svg
This new treatment requires three important steps:

First, it is necessary to harvest a number of these amazingly versatile HSCs from the patients and store them for later use. HSCs are either collected directly from a patients marrow through aspirations performed under general or regional anaesthesia or harvested directly from blood following procedures intended to enrich circulating blood with HSCs. Since HSCs make up only 0.01% of total the nucleated cells in bone marrow, these must be isolated from samples (based on either cell size and density or using antibody based selection methods) and purified before undergoing cryopreservation.

Next, the patient undergoes chemotherapy, with or without the addition of immune-depleting agents. The purpose of this is to eliminate disease in the patient, specifically by destroying the malfunctioning mature immune cells which are erroneously targeting and destroying healthy myelin. Since chemotherapy has a severe toxic effect and can cause damage to the heart, lungs and liver this procedure is currently limited to younger patients.

Finally, the cryopreserved HSCs removed in step one are reintroduced into the patient, a process called hematopoietic stem cells transplantation (HSCT). Given time, these stem cells develop into new immune cells therefore reconstructing the patients immune system. At this stage it is possible that mature, faulty, immune cells may be transplanted back into the patient from the original sample. Therefore, before transplantation procedures are carried out to ensure that few mature immune cells are contained within the transplant.

Each of these steps comes with it’s own scientific challenges, not to mention challenges for patients including the hair loss and severe nausea linked with chemotherapy. But, so far, this treatment has also lead to some absolutely amazing success stories with one, previously wheelchair-bound, sufferer regaining the ability to swim and cycle. However, doctors stress that this is a particularly aggressive form of treatment and that it may not be suitable for all MS sufferers.

Dr Emma Gray, head of clinical trials at UK’s MS Society, said: “Ongoing research suggests stem cell treatments such as HSCT could offer hope, and it’s clear that in the cases highlighted by BBCs Panorama they’ve had a life-changing impact. However, trials have found that while HSCT may be able to stabilise or improve disability in some people with MS it may not be effective for all types of the condition.”

Dr Gray said people should be aware it is an “aggressive treatment that comes with significant risks”, but called for more research into HSCT so there could be greater understanding of its safety and long term effectiveness.

Post by: Sarah Fox

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The astronomy of astrology

It’s been a while since I last posted so instead of talking about the details of using telescopes or taking astrophotographs, I will discuss what for many people are two interchangeable terms: astronomy and astrology. More specifically, this post shows how some interesting oddities of astrology can also interest astronomers.

As a reminder, astrology is the study of the movements of celestial objects with the goal of predicting or justifying life events while astronomy is the scientific study of the properties, interactions and evolution of celestial objects. While I feel that our life choices are not influenced by the movement of the Sun across the zodiac constellations, or the alignment of certain planets I do think that people who believe in astrology may find significant interest in the evidence-based view of the universe astronomers take.

Lets begin by discussing an interesting tenet of astrology: star signs. The 12 signs of the western zodiac are based on the constellations which lay along the path on which the Sun appears to travel over the course of a year. Your star sign should ideally relate to the constellation which the Sun passes through on the day of your birth. But, most the time things are not this simple.

Every year, as the Earth orbits the Sun, the line of sight between us and one zodiac constellation is blocked by the Sun, this means that, as viewed from Earth, the Sun will appear to be sitting within this constellation. However, the dates associated with the star signs have not been technically correct for around 2000 years, i.e. the constellation in which the Sun appears the day of your birth may not fit with your star sign.

This is caused by a discrepancy between the way we define a year and changes in the movement of the Earth. As a society, we define a year as starting on a set date (the 1st of January) and running for a given number of days (365 – or 366 on a leap year). However, a year in astronomical terms is defined as the time it takes for the Earth to revolve once around the Sun, and these two measurements do not necessarily match up.

Figure 1. The position of the vernal equinox in the night sky. The Sun currently passes through this point on the ecliptic (red line) on 20th March. Graphic taken from Stellarium.

Figure 1. The position of the vernal equinox in the night sky. The Sun currently passes through this point on the ecliptic (red line) on 20th March. Graphic taken from Stellarium.

Specifically, in astronomical terms a year consists of the time period between vernal equinoxes. The vernal equinox occurs when the ecliptic (the line the Sun makes across the sky in one year) crosses the celestial equator (an imaginary line projecting out from Earth’s equator into space), see the blue arrow in Figure 1.

However, due to the fact that the Earth slowly wobbles on its axis every 26000 years (called Precession), the date of the vernal equinox slowly shifts by about 1 day every 70 years. The effect of this shifting equinox is that the position of the Sun within different constellations slowly changes, therefore, the Sun may be in a different constellation during the month of your birth than it was when astrological charts were first drawn up. Below is a table comparing traditional star sign dates with the actual position of the sun on these dates.

Screen Shot 2016-01-16 at 22.36.38

The table also includes the length of time the Sun spends in each constellation. As a convenience in astrology, the star signs are given equal lengths. However, in reality, constellations have different sizes and cut across the ecliptic at different angles. The Sun spends 44 days in the constellation Virgo but only 8 days in Scopius (making true solar Scorpios a rare breed!). You may also notice an unfamiliar constellation: Ophiuchus (the serpent barer), it’s a large constellation but only a small part of it is actually crossed by the Sun in early December. Strangely this was known in ancient times but not included as a sign of the zodiac.

Gemini - 2015 Gemini - 28015Figure 2. The motion of the stars over thousands of years changes the constellations. Nearby stars (such as Pollux) appear to move faster. Graphic taken from Stellarium.

Gemini – 2015
Gemini – 28015Figure 2. The motion of the stars over thousands of years changes the constellations. Nearby stars (such as Pollux) appear to move faster. Graphic taken from Stellarium.

So when will the traditional star sign dates once again match up with the position of the sun within these constellations? Well, this could happen in about 24000 years, after the Earth has completed a full precession rotation. However, by then the stars themselves will have moved relative to each other, changing the shape of the constellations forever. In Figure 2, the constellation Gemini (my true solar star sign) is shown as it appears now (2015), and how it is projected to appear after 26000 years of star movement (date 26000 + 2015).

All of this serves as a reminder that the universe does not neatly fit into equally spaced constellations or fixed calendars, instead it is amazingly complex and constantly changing. So perhaps astrology can be a starting point for peoples’ interest in the universe, or at least to getting a better understanding of the science behind the horoscopes.

Post by Daniel Elijah

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