Archives for posts with tag: astronomy

I had the privilege of speaking at the First Friday’s at the Castle in CIT Blackrock Castle this weekend. My talk was “Hoaxes and Hysteria in Astronomy”, where I took a sceptical look at Astrology, UFO’s and the Moon Landing “Hoax” conspiracy theory.

I first spoke about astrology. To understand why astrology is wrong, you need to understand how it originated, and how astronomical discoveries since the 1500’s have completely overturned the basis of the belief system. It also gave me the opportunity to present Phil Plait’s frequently posted diagram:

Then I gave a potted history of UFO’s and our culture’s fascination with all things extraterrestrial. Part of it featured Orson Welles’ infamous radio broadcast that panicked half of America in 1938. Here is the first piece of the radio show. Even now, over 70 years later, it still works as a monumental piece of broadcasting.

Orson Welles later described why he did it:

 

While a great many people claim to have seen UFO’s, there has never been any hard evidence provided. UFO reports have been plagued by problems of mistaken identity, delusion and hoaxes. One of the best hoaxes was crop circles: initiated by two drinking buddies in the south of England.

I then spoke about the widespread perception that the moon landings of the late 1960’s and early 1970’s were a hoax and that NASA staged a cover-up of monumental proportions. There have been many rebuttals, most comprehensively done by the Mythbusters team.

Personally, I love Michell and Webb’s take on it.

At the end of the talk, I got around to my Baloney Detector Kit:

That last one, the “lone mavericks” suffering for their ideas, is particularly true. There have been far, far more wrong-headed lone mavericks” in history than the tiny number of people who have eventually been proven right.

Finally, if you have managed to read through to the end, here are some useful links should you wish to know more.

  1. BadAstronomy.com : Phil Plait waxes lyrical about his wonderment of the universe, while regularly debunking the widespread misinformation.
  2. Snopes.com : If you hear a strange tale or you get an email that sounds fishy, check this website out. It will give you some food for thought.
  3. Skepdic.com : The Skeptic’s Dictionary is a tremendous resource for people who want to understand the scientific view of modern delusions and weirdness.
  4. Randi.org : The James Randi Educational Foundation has been fighting baloney for years. There are plenty of resources there for budding sceptics.
  5. Skeptoid.com : Brian Dunning has created a comprehensive list of ten-minute podcasts debunking all sorts of strange ideas. You name it, it’s probably there.

We run regular “Skeptics in the Castle” meetings in Blackrock Castle, where experts are invited to talk about the reality behind modern misconceptions, fads and strange beliefs. Check out our website corkskeptics.org. We are also on Facebook and Twitter.

In 1584, the philosopher Giordano Bruno speculated that the Universe might be full of planets just like our own. For daring leaps of the imagination such as this, the Church duly branded him a heretic, rewarding him with imprisonment and a fiery death at the stake.

Today, we went one step further to proving him right. At a press conference earlier today, astronomers announced the discovery of two planets the same size as the Earth. These are the smallest planets ever discovered outside our solar system and the first definitive proof that worlds on a similar scale as our own exist.

The planets, Kepler 20-e and Kepler 20-f, are very close to their parent star, and therefore too hot to bear any real similarity to our home world. The news comes hot on the heels of the discovery of a planet in the “habitable zone” around a star, where it is possible for water to exist in liquid form. We are now hot on the trail of a planet that meets all the basic criteria for supporting life.

The discovery comes via Kepler: a space telescope that is surveying thousands of stars in a small area of the sky, roughly in the region of the Summer Triangle. It records the light emitted from each of the stars over time, playing close attention to any slight dips in brightness. These dips may indicate a planet moving in front of the star and momentarily blocking its light. Kepler’s systematic approach has revolutionised the science of planet hunting. To date, with just over a year’s data processed, it has found over 1,200 candidate planets.

It is surely only a short time now before a small Earthlike planet is discovered that is just the right distance from it’s parent star to support life. Who knows what may be discovered in the future about these small, watery worlds? We live in hope.

As people on Twitter might know, I have a thing about the Space Shuttle. I was my son’s age when the Shuttle first launched itself into space. I gasped with incomprehension when the Challenger exploded. Many times I rushed outside at just the right time to see it fly over. On a few rare occasions, I was one of the first people in Europe to see it just after launch: its jettisoned fuel tank descending below it.

They needed to be retired. The fleet was long past its use-by date. They were using technology from the dawn of the computer age. They were dangerous and ridiculously expensive. The International Space Station has been completed. There are now other ways to send crews and supplies to it. There was no rational reason to extend its lifetime.

Nevertheless, I am sorry to see it go. I would have loved to see a launch first hand, to hear the roar as it rose above the atmosphere in a matter of minutes. No matter what comes next, the Space Shuttle program will be missed, if only because we are reminded, in a very tangible way, that 30 years have now passed us by.

Here is a great video which quickly recounts entire program, its highs and its lows, from 1981 to 2011. Let’s hope that the next few decades will inspire us even more.

It sounds like a tall tale thought up by a seven-year old Mr Gadget fanatic, but it’s true: the good folk in Cork Institute of Technology (CIT) have commissioned a large 32 metre transmitter just north of Midleton, Co. Cork for radio astronomy.

The site was originally developed in the 1980’s as a satellite transmission site for the Irish telecoms agency (now Eircom) to enable international communications. As is typical of the industry, it was already defunct by the mid-1990’s, with optical fibre replacing satellite as the primary medium for global telephony. The site was mothballed and in 2009, it was sold by Eircom to a private company.

The use of the site as a radio telescope is terrific from a number of standpoints. It will help to develop skills in space-science here in Ireland. It will provide fantastic outreach opportunities for kids who might be interested in science as a career. With CIT’s backing, it will create a focus for international research projects. It also has tourism potential for the east Cork region. Win, win, win, win!

I am genuinely delighted for the hardworking team in CIT and Blackrock castle, including Niall, Claire and Alan, Deirdre and Francis, all of whom I have had the pleasure to get to know in the last year. With their involvement and leadership, this is going to be a huge success.

I have a very fond memory of the station, in that it was the very place where I saw the fabulous auroras in October 2003. It’s a memory that I will never forget.

News reporting: Irish Examiner article. Irish Times article.

 

Photo via mitopoietico (Flickr / CC Licensed)

So, you are out one night and you see an object in the sky that you can’t quite explain. You have never seen anything quite like it in your life before. Could it be an alien spacecraft? Have you had a Close Encounter of the Third Kind?

An alien visitation would be a truly outstanding occurrence if it were validated scientifically. It would possibly rank as the greatest discovery ever since science began. For centuries however, astronomers, both professional and amateur, have been looking into the skies without ever finding good evidence for the existence of extraterrestrial beings. Given our knowledge of the Universe, this is not surprising. Although there are many billions of stars around us, the distances involved are stupendously large. The practical difficulties involved for alien spacecraft traveling to Earth beggar belief. This is not to say it is impossible; just very unlikely. When you see a strange light in the sky, you should not jump to the conclusion that you have seen a UFO. Other, more mundane explanations are possible in the majority of cases.

Here’s a quick guide to some strange lights in the night sky, and what they might be.

  • Steady moving lights, flashing each second, possibly green or red; sometimes very bright white lights.

It’s likely to be an aircraft. This is probably a trivial case as most people are aware of what planes look like at night. Near airports, planes can have very bright landing lights turned on that can drown out any flashing beacons.

  • Steady moving light with no flashing. Moving slowly. Seen after sunset or before sunrise. Can be very bright, but usually quite dim objects. May disappear almost instantaneously.

You may have seen an artificial satellite. There are hundreds of satellites in the sky, normally only visible in the night sky after sun-down, when the light is still shining on them. The sudden disappearance happens when it moves into the Earth’s shadow. If the light is very bright, it is likely that you have just seen the International Space Station, quite a common sight in our skies these days.

  • Orange flickering light, floating around 50 to 100 metres above the ground. May dim slowly after a few minutes.

You have possibly seen a Chinese Lantern, a small, inexpensive hot-air balloon made out of paper and wire. Chinese Lanterns have become very common around the country at celebrations, Halloween and New Year’s Eve.

  • Steady bright light. No apparent movement. May be close to horizon or visible in the southern sky. Much brighter than surrounding stars.

It’s possible you have seen Jupiter or Venus, two surprisingly bright planets at certain times of the year. After the Moon, these two objects are the brightest objects in the night sky.

  • A very bright point of light in the sky. It lasts momentarily, then disappears again. Object may move slowly. So bright you might even see it during the day.

You may have seen an Iridium Flare, essentially the reflection of a low-orbit Iridium satellite, originally used to provide satellite mobile communications. The reflections can be surprisingly bright.

  • Very bright green or red light in the sky, about 200 metres above ground. Appears to move slowly.

You may have seen an emergency flare. This is a very bright firework, shot up in the sky as a distress signal to nearby shipping. In Ireland, flares are often sent up during celebrations like the New Year.

  • Fast moving bright object. May travel a large distance across the sky in a split second. Possibly a greenish colour associated with the event.

You may have seen a fireball. This is a rocky object from space that has collided with the Earth’s atmosphere, heating up and exploding on impact. It may also be a satellite re-entering the Earth’s atmosphere. Such an event is worth noting! You should make a note of your observation with the International Meteor Organisation.

  • Strange diffuse lights, illuminating clouds. Moving rapidly, possibly rhythmically. There may be more than one light in the sky.

You may have seen the effect of searchlights shining up on clouds. Local festivals and event organisers sometimes use searchlights to attract attention to their shows at night.

Other sightings may have arisen from light reflections, optical illusions or mistaken identity. It may be that the witnesses were very tired at the time or under the influence of drugs or medication, or they may have been the subject or originator of a deliberate hoax. The key thing is to always discount the more mundane answers before ever jumping to improbable conclusions.

Tonight I am performing cutting-edge science. I am searching for planets revolving around stars some quadrillions of kilometres from here. My equipment? A laptop and an Internet connection. The cost? Just a bit of my time. The possible benefit? Contributing to discovery of entirely new worlds.

On December 16th, a new project – Planet Hunters – was put online. The aim is simple. You are given a whole series of light curves (graphs) from different stars, and your mission – should you choose to accept it – is to identify anything that might indicate a planet crossing in front of its parent star. It’s easy to learn. In a few minutes you can be searching for far-away planets like an expert.

Planet Hunters uses data from a satellite known as Kepler, whose job it is to study hundreds of thousands of stars over an extended period, looking for signs of planets crossing in front of their parent stars. Planets are very dim compared to stars, so they are almost impossible to detect visually. However if they happen to cross in front of a star, the light from that star decreases momentarily. This decrease can be picked up by powerful telescopes and it is these occurrences that Kepler is keeping a lookout for.

That’s where we citizen scientists come in. Many of these small drops in brightness are not easily detectable by computers. Humans are good pattern recognisers, so we can often see anomalies that a computer might not recognise. Searching through the light curves for transiting planets is a bit like finding a needle in a haystack. The planet, the star and the Earth need to line up exactly, so only a small percentage of stars are likely to show anything of interest, even if they have planets revolving around them. If enough stars are sampled however, new planets will certainly be discovered. Some scientists reckon that Kepler will quadruple the number of exoplanets known to us. We currently know of 700 planets revolving around stars other than our sun.

What hit me about searching were the many different types of light curves available. Many stars are relatively uniform, but others show complex variations and rapid fluctuations. The picture below gives you an indication of some of the star patterns I came across today.

So far in my searches I have come across a few patterns that may indicate a planetary transit. The software permits you to tag and highlight possible candidates. The same pattern is shown simultaneously to other users, so that comparisons can be made and observation errors reduced. If many people are tagging the same feature, then it is likely that something interesting is going on. Having us “citizen scientists” involved is of huge benefit to the real scientists,who would otherwise need to sort through a deluge of data.

Here are my 4 best candidates from my searches so far. They may turn out to be nothing of importance, but in any case for a few hours searching it’s been a fascinating introduction to the world of planetary discovery.

What a tremendous and wholly unexpected reaction to my “Five Reasons” post last Friday. To everyone who commented, “Liked” or shared my entry I would like to thank you all.

The entry had been in the works over several weeks due a renewed interest in astronomy caused in no small part by a recent visit to some huge meteorite craters in Germany. I had refrained from posting it earlier because of some problems with wording. I certainly didn’t expect it to get much of a reaction because my posting has been quite sporadic lately and comments tended to be few and far between.

How wrong I was. The entry was placed in a prominent position on WordPress’ Freshly Pressed page, and the numbers began to shoot up immediately. My initial reaction was that I was the victim of a spam attack, but after reading the comments I was delighted to discover that something entirely different was happening. My site got thousands of hits over the weekend with over 120 comments to the entry at the time of writing, many of them very positive and supportive.

Some of the commenters were exceptionally kind. Many of you share my love of the stars and planets and the sense of wonder it creates. A few of you lamented the lack of light available in urban areas – a concern I share too. Here is a small selection of comments from you that I thought I would respond to.

Ishana wrote:

Nothing is more fascinating than that which we cannot obtain.

Very true. But who knows what awaits us in the future? Arthur C. Clarke once said that when a distinguished but elderly scientist declares that something is impossible, he is probably wrong. I think we have a lot to learn yet, but yes, it seems there will always be an “unobtainable” when it comes to the vastness of the Universe.

CommentatorandPoet said some particularly nice things about my use of the English language, and I would like to thank him for this. If only I could always be so fluent, as it often takes quite a bit of work for me to come up with the right words.

Nora Weston said

“Every time I venture into virtual space to find information and photographs…I’m left in awe”

A great point Nora. Astronomy is not just about what we can see, but what these amazing instruments such as Hubble can perceive. We can experience so much just sitting at our desktops now.

Pduan quoted Carl Sagan, one of the foremost science communicators of the last century.

“every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.”

This piece of writing should be on the desk of every politician and religious leader in the world.

Rebelliousvanilla said

“I was laying on my back on the grass during the night and looking at the stars and thinking that if a civilization advanced enough to see details on Earth’s surface will look this way from Andromeda in 2 million years, they will see me, laying on the grass, looking towards them.”

You never know. Keep having weird thoughts, RV.

Chemical Marriage said

“Plus, IT IS HUGE! Space is a never ending hill to look over.”

Spot on and well said. I just quoted five reasons. I’m sure there are hundreds.

mndals said

“The universe is indeed filled with wonders and the more we learn about it the more wondrous it becomes.”

So true. We are only now beginning to learn about planets around nearby stars, and their strange and wonderful ways. What next? Life?

Last but not least, Tom Baker said

“I think my favorite heavenly body is my wife, but next to her is the Horsehead Nebula.”

Thanks Tom! That brought a smile to my face.

These are just a selection of the comments. I will try to visit as many of your blogs as possible over the coming days to see what I can find.

Thanks again for all your kind words.

It’s beautiful

If you go out on a dark moonless night, you will immediately know what I mean. The Milky Way, stretching its jagged course across the heavens, is quite a sight to behold. The constellations, particularly the winter constellations, have an elegance and familiarity to them. The Moon is also an appealing object, with its ever changing phases and frequent conjunctions with other planets in the sky. Through a small telescope, planetary disks, galaxies, nebulae and open clusters come into view, often startling in their majesty.

Of course, the beauty of the universe is not limited to what is immediately visible to our eyes. Deep space objects, seen through the largest of telescopes, are candidates for some of the most beautiful things ever seen by human eyes. Who could not fail to be impressed by the wonderful Hubble photos of the Crab and Eagle nebulas, or the views of the outer planets and moons from space probes such as Voyager and Cassini? To see for yourself, each day NASA publishes it’s Astronomy Picture of the Day. Few images ever fail to impress.

It’s extreme.

Nothing can be taken for granted about space. Most of it is unimaginably cold, interspersed occasionally by blisteringly hot stars with coronal temperatures of millions of degrees. Almost everything is racing around at breakneck speed: barreling through space at velocities of hundreds or thousands of kilometers a second relative to us. That’s enough to cause quite an impact if we were to get in their way. All around us catastrophic convulsions are taking place, with vast explosions and unconscionably high energies. This is a Universe of supernovas, neutron stars, magnetars, pulsars and Gamma Ray Bursts – beams of high energy radiation that would eliminate all life on our planet in an instant were our Earth unfortunate enough to stray too close. Black holes exist that can compress the mass of whole stars into volumes a few kilometers wide, creating gravitational fields that nothing, not even light itself, can escape from.

This is the stuff of childhood fantasies. Superpowers. Forcefields. Instantaneous death. The destruction of worlds. It is no wonder that space features so prominently in the minds of the young.

It ignites our curiosity.

Astronomy confronts us with some of the biggest and most challenging problems about the nature of ourselves and the fabric of reality. As a science, it has lead the way in overturning ancient notions of how nature should behave. At one time we believed ourselves to be at the centre of the Universe, with all objects, including the Sun, revolving around the Earth. Astronomers through the ages slowly revealed a different truth. Our star and our home planet are among countless billions in a very ancient Universe. Everything we do ultimately only affects an infinitesimally small piece of real-estate in the cosmos. This discovery, while deeply humbling, is enlightening. It tells us that we will never know everything. Our quest for knowledge is unlimited. We are ants in a cathedral, and what a cathedral it is.

The study of the stars and planets has pushed out the frontiers of knowledge in every direction. It’s contribution to science and mathematics cannot be underestimated. Without astronomy, the modern world as we know it would not exist. Astronomy continues to confound us and guide us right to this day. Gigantic accelerators are busy smashing sub-atomic particles into smithereens to gain greater insights into the nature of matter because objects in space do not always behave the way our current scientific models expect them to. Astronomy has revolutionised our understanding of nature and it will continue to do so.

It tells us about our past.

When you look into space, at any star you care to mention, you are looking into history. You are not seeing the star as it is now, but as it was when the photons of light left its photosphere many years ago. If you can find the Andromeda Galaxy in the sky, you are getting a picture of how it looked two million years ago, long before humans ever roamed our planet. The largest telescopes can see back billions of years ago, to galaxies in their infancy, still in the process of being formed.

History is about ourselves, how we got here, why things are how they are. Astronomy opens history even further by explaining the origins of our planet, our sun, our galaxy – even providing insights into our Universe and how it all started some 13 odd billion years ago.

Astronomy is fascinating even when applied to our own modest human story. We have had an intense relationship with the stars and planets for thousands of years. It guided the ancient cycles of sowing and harvesting. It provided the raw material for belief systems, rituals and religions. It contributed to our language. It assisted with navigation and discovery. In living memory, we have witnessed men walking on the Moon and robot probes being flung out of the solar system – events likely to be celebrated for millennia to come. Our relationship with the stars has shaped the culture of today.

It’s our future.

Astronomy is important to our future, from the short term to the distant long term. Over the coming decades, private companies will take over much of the heavy lifting formerly associated with government agencies such as NASA and ESA. This will create new jobs and new wealth. Bigger telescopes and better equipment will provide insights into reality that will stretch our technological capabilities. Over the coming centuries perhaps we will explore and colonise deep space for ourselves, using technologies yet undreamt of. In the end, billions of years from now, our sun will expand, frying everything on this planet before diminishing in size itself, its fuel spent, its job done.

Perhaps there is a large asteroid or comet out there in space with our name on it. Perhaps our planet will eventually turn against us, forcing us to find a new home. Perhaps we will find a way to cross the enormous gulfs separating us from other stars in our galaxy. All of these possibilities lead us to the conclusion that the stars will feature prominently in the future of the human race.

Astronomy is available to all, from the small child with his toy rocketship, to the octogenarian peering through her telescope at a crater on the Moon. Few endeavours are so wide in scope, so rich in detail, or so marvelous in implication. I invite you to join in.

This blog entry was written to accompany my podcast for the September 5, 2010 broadcast of the 365 Days of Astronomy. The podcast can be listened to here.

One of the high points of my stay in Germany recently was a visit I made to Nördlingen on the border between the provinces of Bavaria and Baden-Württemberg in southern Germany. It’s a beautiful place. It is enclosed by a defensive wall that dates back to the 14th Century – there are only three towns in Germany with this claim to fame. All the buildings are full of character. The town was the site of two battles during the Thirty Years War and were it not for the cars and the shops, you could easily imagine yourself in another time, another era.

But beautiful and all though the town is, this is not the reason I went there. It’s Nordlingen’s surroundings that interested me the most. The town is located in a region known as the Ries: a round, flat plain with an approximate diameter of around 23 km (15 miles).  This area is quite different to the surrounding countryside as the following scale model clearly indicates.

For many centuries, the prevailing idea about how this geological feature came to be was that it was an ancient volcanic caldera. The trouble was that much of the boulders and debris surrounding the  region were of non-volcanic origin. Many ideas were presented as to how this material got there, but it’s didn’t fully add up. The origins of the Ries remained controversial until fifty years ago.

Enter Eugene “Gene” Shoemaker. Gene was an astronomer and he had a few questions. When he looked at the Moon he saw a landscape quite different to the Earth. Everywhere on the Moon he saw craters. Big craters, small craters, enormous craters. Why then was the Earth practically devoid of them? Was it credible that the Moon could be subject to the slings and arrows of outrageous impacts while its larger sister, our planetary home, missed them all? He was convinced that the evidence for impact craters must exist on Earth, but where were they all? Gene had a good idea what kind of material would be created when a large object hit the Earth. It was just a matter of finding it.

Gene found the answer in Nordlingen. During a visit to the town in 1960 he became fascinated by the stones of St Georg’s Church in the centre of the town. He immediately realised that the church walls contained coesite, a material only created as a result of a massive meteorite impact. The rock had been mined locally from the Ries. This lead to a simple, stark conclusion. The Ries had been formed as a result of a gigantic meteor impact. “It was the first big impact crater on the Earth that we could prove was an impact crater, and that just changed the whole ballgame”, said Shoemaker.
Here is what we know. 15 million years ago, two large objects, one measuring up to 1km in diameter, crashed into southern Germany. The large object hit Nordlingen. Hitting the ground at a speed of 45,000 km per hour, it punched a hole 4km deep into Earth’s crust, vaporising on impact. The surrounding rocks were compressed to a quarter of their size by the impact and they responded with an explosion measuring 18,000 megatonnes of TNT, hundreds of times larger than the greatest nuclear bomb ever detonated on this planet. An enormous shock wave killed all living things for a hundred kilometers in every direction with devastating effects felt much further afield. A mushroom cloud 30km high was generated. Much of this cloud, composed of melted rock from deep within the crust, subsequently fell back to earth, covering the crater and the region around the Ries with a material known today as Suevite. The church of St Georg in Nordlingen is built from this material.
A massive amount of bedrock was ejected ballistically, forming rocks known as Bunte Breccia. The deepest rocks landed close to the impact zone while rocks close to the surface were hurled over great distances. Some limestone blocks have been found 70km from the crater while glassy rocks known as Moldavites have been discovered 400km away in the Czech Republic.
The 1km deep hole left by the impact became a lake and life returned to the Ries. Over time the lake itself became clogged with sediment and subsequent glaciations flattened out the region into the wide plain we see today.
A particularly good place to see the crater expanse is the Daniel, the steeple of the aforementioned St. Georg’s Church. From a height of 80 metres you can see in all directions the flat, fertile countryside with the hills forming the outer crater in the far distance.
A smaller meteorite simultaneously hit the region of Steinheim am Albuch, 40km away from Nordlingen. While the resulting crater was much smaller – just 3km in diameter – a distinct central uplift remains. Steinheim is a village well worth visiting. There is an excellent little museum in the hamlet of Sontheim im Stubenthal and plenty of well marked trails with wonderful views of the crater.
Addresses
Nordlingen:
Rieskrater Museum
Hintere Gerbergasse 3
86720 Nördlingen, Deutschland
09081 273822-0
Steinheim
Meteorkratermuseum
Hochfeldweg 5
89555 Steinheim, Deutschland

Next Sunday, September 5th, The 365 Days of Astronomy website will be broadcasting my second podcast.

It’s all about two gigantic meteor craters in the heart of Europe. I talk about how they were created, what they look like today and how their discovery has changed the way we look at our planet. I will be backing up the podcast with pictures and further details here on this blog.

Please take a listen in and let me know what you think.

(Oh, and if you never heard my first podcast for 365DOA, you can find it here).

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