Observatory Stuff

Beez Neez now Chy Whella
Big Bear and Pepe Millard
Mon 7 Jul 2014 22:47
Stuff from the Observatory – If you read this, you really have
to get out more...........it’s for me – however the Māori Bit at the End is
Interesting. ![]() 13.7 BILLION YEARS
BACK............ OK that caught my attention, has someone studied the
time when Bear began to snore.........to the moment when it burst onto being out
of the void. The Big Bang. Oh. I haven’t listened to my Albert Einstein or
Stephen Hawking audiobooks yet, so this was fascinating for me to learn about
things that I have no grasp of. We watched some short videos with comments from
men with brains the size of Britain, I followed them on stars, galaxies, the
Universe and was quite excited that I could keep up, that was until the comment
in Black Holes when the chap said ”when space and time turns in on itself” –
what........Here’s what I did understand.
13.7 billion years ago the Universe burst
into being., expanding from a single point – the Big Bang. How do we know?
Because we can see that it is still expanding. When we look at faraway galaxies,
we can see that they are moving away from us very quickly. If the galaxies are
moving apart, they must have been densely packed together in a tiny space. By
calculating how fast the Universe is expanding – and making allowances for the
evidence that this expansion may have sped up over time – astronomers can
calculate when the Big Bang happened.
![]() 0.000000000000000000000000000000000000000001 seconds after the Big
Bang the Universe was this size.
The Void: It’s impossible
for us to know what happened before the Big Bang, because space and time did not
exist. As Saint Augustine put it in the 5th century, “there was no ‘then’ when
there was no time.” The Universe itself, emerging from the timeless void,
created space, time and energy.
Time: After the Big Bang,
the cosmic clock began to tick. After the tiniest fraction of a second, a
ten-trillionth of a quadrillionth of a second, to be precise – the entire
Universe would have been contained within a single grain of sand. A microsecond
later, it measured 100 billion kilometres across – nearly 700 times the distance
from Earth to the Sun.
![]() In the first seconds after the Big Bang
the Universe was far too hot for matter to form. But from the moment it started
expanding, the Universe was cooling down. Within five minutes, the Universe had
cooked up electrons, neutrons and protons – the basic ingredients needed to make
matter.
Light: When electrons,
neutrons and protons first formed, there was still too much energy for them to
come together to make atoms. Instead, they seethed and swirled in a super-heated
soup. Photons – particles of light – zigzagged from one charged particle to the
other, unable to escape. Then, about 300,000 years after the Big Bang, it became
cool enough for the positive and negative particles to stick together. The first
atoms formed. The cosmic fog enveloping the infant Universe became transparent
and there was light.
![]() Cosmic Microwave Background
Radiation: The cooled down light left over from the Big Bang is still
shining all around us. But the expanding Universe has stretched it so much that
we can’t see it at all – we can only detect it as microwave radiation. Theorists
predicted the existence of the cosmic microwave background radiation in 1948.
Two decades later, two radio astronomers investigated a mysterious hiss caused
by interference in their receiver. At first they thought poo from pigeons
nesting in their antenna was to blame for the background noise. Finally, after
ruling out all possible sources, they realised that what they were hearing was
an echo of the Big bang itself. When we tune between stations on the radio,
about 1% of the static we hear is from the same source.
A Lumpy Universe:
Spacecraft and satellite missions have found tiny variations in the cosmic
microwave background radiation – evidence of the microscopic irregularities in
the early Universe. It was those irregularities that would allow matter to clump
together to form galaxies, stars, planets...... and us.
Matter: When particles
created in the first five minutes after the Big Bang joined up 300,000 years
later, they created the two simplest and lightest atoms – hydrogen and helium.
Hydrogen is by far the most common element in the Universe, making up over 74%
of all matter. Helium makes up nearly all the rest – 23%. All the other elements – the carbon in our bodies, the oxygen we
breathe and everything else – make up just over 2%, and were made long after the
Big Bang, in stars.
![]() A photograph
of Something We Can’t See: We can’t see dark matter, because it
doesn’t reflect or emit light. But it can be detected indirectly through its
gravitational effects on stars and galaxies.
Dark Matter:
Astonishingly, the ordinary matter that we, and everything we can see or touch,
are made of seems to be only part of the story. Astronomers have calculated that
there is not enough ordinary matter to generate the gravity needed to hold
galaxies together. There is something else out there, something massive we can’t
see – dark matter. Some dark matter is stuff we know but can’t see because it
doesn’t shine, like black holes, dim stars and planets. But most of it,
astronomers believe, is an exotic form of matter we haven’t yet
identified.
Dark Energy: Since the
early 20th century, astronomers have known that the Universe is expanding. More
recent observations tell us that the expansion is actually speeding up. Dark
energy is the accelerator that’s stretching space, overriding the ‘brake’ of
gravity. What is it? We simply don’t know. Dark energy could be a radical form
of matter, a type of anti- gravity force, or simply a mysterious property of
space itself. Whatever it is, dark energy is locked in an eternal arm-wrestling
competition with gravity. About six billion years ago, it seems that dark energy
began to prevail – and it’s been pushing the Universe outwards at an increasing
rate ever since.
Ordinary matter makes up about 4% of the
Universe’s total mass/energy. Dark matter makes up 22%. Dark energy makes up
74%. But most of the Universe is simply empty space. If the Universe was the
size of the Observatory in which we are now standing – people, stars and
galaxies – would fit within a single grain of sand. I think I now know I need to
get out more........
![]() How will the Universe end ?
Whimper: If dark energy
wins its battle against gravity, the Universe will continue to expand forever,
becoming more and more diluted by empty space. Many billions of years from now
the Universe will become totally cold. Black holes will evaporate and the stars
will go out.
Bang: If, on the
other hand, the Universe contains enough mass, the current expansion will
ultimately slow down, halt, and then reverse as it collapses under its own
weight. Everything in the Universe will crunch back into the infinitely small
point from which it began.
Maybe it won’t? Some
physicists have theorised that our Universe is in fact just one of an infinite
number of universes, known as the Multiverse. One prediction of the Multiverse
theory is an endless series of Big Bang, as universes collide in multiple
dimensions.
![]() The Hubble Ultra Deep
Field is a photograph of a tiny patch of the night sky, taken by the
Hubble Space Telescope. Almost every dot of light is a distant galaxy. The most
distant galaxies are seen as they were nearly thirteen billion years ago,
because that’s how long it has taken for their light to reach
Earth.
![]() Galaxies are
large structures of stars, dust and gas, bound together by gravity. There are
hundreds of billions of galaxies, containing almost all the Universe’s visible
matter. They are threaded through the Universe’s vast empty voids in filaments
and clusters many billions of light years long. Galaxies vary in size from dim,
sparsely populated dwarfs to huge elliptical galaxies, jam-packed with trillions
of stars. All are believed to be surrounded by vast haloes of dark
matter.
![]() The Discovery of Other
Galaxies: Until the early 20th century, many scientists believed that
our galaxy, the Milky Way, was the Universe. As early as the 18th century,
astronomers had noticed faint smudges of light too blurry to be stars – but not
moving, like a comet would be. But there was no way of proving whether these
strange luminous objects were within the Milky Way or outside it. It wasn’t
until 1923, when the American Edwin Hubble used the
most powerful telescope of the time to observe one of these hazy clouds of
light, that the question was settled. What Hubble saw in it was a type of star
whose real brightness was known. By measuring how bright it appeared to us on
Earth he could calculate its distance from us.
His conclusion: It was
far, far outside the Milky Way. In other words, it was another galaxy –
Andromeda. Suddenly, the Universe was much, much bigger.
![]() A Galactic Tape Measure:
The stars Hubble used to measure the distance to the Andromeda galaxy are called
Cepheid variables. Their brightness varies at regular intervals in cycles that
range from days to months. While studying a group of Cepheid variables in the
Large Magellanic Cloud, Harvard astronomer Henrietta Leavitt discovered that the
length of each star’s cycle was directly related to its brightness. The longer
the pulse, the bigger and brighter the star. By noting the length of a Cepheid
variable’s cycle, astronomers can tell how bright it really is. And by
measuring how bright it seems to us on Earth, they can determine how far away it
is.
![]() Clouds of star-forming matter are known as
nebulae. Triggered by shock waves caused by an exploding star, or some other
kind of galactic disturbance, cold gas and dust in the nebula clump together to
form a cluster of proto-stars. Squeezed by gravity, hydrogen atoms in each
proto-star’s core start to fuse in a violent series of nuclear, reactions,
releasing enormous amounts of energy. A star is
born.
![]() ![]() Weighty Matters: As the
elements within them fuse together, stars continue the matter-making work begun
in the massive temperatures immediately following the Big Bang. For most of the
star’s life, it is powered by hydrogen fusing to helium in its core. But when
hydrogen runs out, the dying star starts burning its helium reserves. In a star
the size of our Sun, helium fuses to produce carbon, oxygen and nitrogen. In
bigger stars, the process continues all the way up to iron.
As a star exhausts its gas supplies, the
core gets hotter and denser. Heavier and heavier elements form in layers, just
like an onion. In a star twenty five times the mass of our Sun, the hydrogen
burning stage lasts about seven million years. Neon burns over a year, oxygen
over six months, and silicon in the course of a single day.
Hydrogen and oxygen: Each
molecule of water is made up of two hydrogen atoms and one oxygen atom. Hydrogen
is the most common element in the Universe. The hydrogen in this water was formed nearly 13.7 billion years ago, as soon as
the Universe became cool enough for electrons and protons to stick together.
Oxygen is the third most common element in the Universe. These atoms were formed
over 4.6 billion years ago, in a star the size of our Sun or larger.
Silicon is the
second most common element in the Earth’s crust after oxygen. It’s used to make
integrated circuits because it is a semiconductor whose ability to conduct
electricity can be easily adjusted.
Carbon is the
fourth most common element in the Universe. It too is created in medium- and
large-sized stars. Carbon’s ability to form many bonds makes it a key ingredient
of life as we know it.
![]() ![]() Iron is the
sixth most common element in the Universe and is created in large stars. The
core of our planet is mainly iron. There’s also an iron atom in each molecule of
haemoglobin, the chemical in our blood that carries oxygen from the lungs to the
body. All the atoms of gold
and silver found on Earth were created in supernovae – the explosive
final moments of huge dying stars – over 4.6 billion years ago.
![]() Death of the
Sun: Our 4.6 billion year-old Sun is a middle-aged, middle-sized star. In
another five billion years, the hydrogen in the Sun’s core will run out. The Sun
will become a bloated red giant and expand to engulf Mercury and Venus, and
maybe even Earth and Mars too. When the dying Sun has exhausted all its gas
supplies, its core will collapse into a tiny, hot mass called a white dwarf,
which will very slowly cool and dim. Its outer atmosphere, containing many of
the new elements it has created over its lifetime, will puff away and disperse
through space, waiting for another cycle of star birth to begin.
The Fate of Stars: The
life cycle of a star – and its fate – are determined by its mass. Stars the size
of our Sun and smaller collapse into white dwarfs made of carbon. Much larger
stars burn out much more quickly, creating heavier and heavier elements, right
up to iron. They also have more dramatic endings, collapsing under their own
weight but then exploding outwards in one of the most spectacular events in the
cosmos: a supernova. All the elements heavier than iron – including gold,
mercury, uranium and lead – are formed in a fraction of a second by the intense
forces generated in the supernova explosion as the greatest of these stars
die.
![]() Supernova 1987A:
Supernovae are rare galactic events. When they happen, they can outshine an
entire galaxy. In 1987, New Zealand astronomer Albert Jones was one of the first
to see this supernova in a nearby galaxy, the Large Magellanic Cloud. At its
brightest, Supernova 1987A – 180,000 light years away
– was visible to the naked eye in the Southern Hemisphere.
![]() The Universe, Everything and
Life: Somehow, out of the lifeless elements, life emerged on Earth. A
few billion years later we evolved: conscious creatures capable of finding out
about the Universe, and communicating with other forms of life out there – if
there are any.... For the meantime I have quite enough to get straight in my
head.
J.B.S. Haldane said “My own suspicion is
that the Universe is not only queerer than we suppose, but queerer than we can
suppose.
I feel no need to disagree with this
sentiment.
![]() Neutron Stars: Neutron
stars are very small, extremely dense stars. A teaspoon or two of the stuff from
the inside of a neutron star would weigh about as much as all six billion people
on our planet put together. As their name suggests, neutron stars are made
almost entirely of neutrons – subatomic particles with no electrical charge.
Neutrons can pack together much more densely then ordinary atoms, which have
positively charged protons and negatively charged electrons that push each other
apart. In fact, neutron stars are typically less than twelve kilometres across.
Neutron stars are formed when a star explodes in a supernova and leaves behind a
remnant with a mass somewhat greater than our Sun. If the remnant is more than
five times bigger, it will collapse even further to form a
black hole.
![]() ![]() ![]() Monsters on the Edge of the
Observable Universe: Quasars are very distant galaxies that are among
the furthest objects astronomers have detected. Because quasars are so far away,
their light has been taken billions of years to get to us – which means they can
show us what galaxies were like when the Universe was young and violent. Every
quasar has a star-eating vortex at its centre – a supermassive black hole. The
black hole is surrounded by a huge whirlpool of half-digested stellar material,
and spits out a thin jet of highly-charged particles light years long.
Quasars were first detected by radio astronomy:’quasar’ is short for
quasi-stellar radio source. But quasars also produce enormous amounts of energy
in the form of x-rays, gamma rays and ultraviolet light. A single quasar can
produce a thousand times more energy than a galaxy like the Milky Way. In fact,
spiral galaxies like our own may be ex-quasars that have calmed down as they
reached middle age, with their stars forming stable orbits around a less active
black hole.
![]() Black Holes: Black holes
are areas of space so dense that nothing that crosses the event horizon can
escape their gravitational pull: not stray astronauts, not massive stars – not
even light. Black holes are created when a huge amount of matter collapses under
its own weight – for example, when a giant star runs out of fuel and
self-destructs in a supernova. Supermassive black holes found at the centre of
galaxies like our own may be as massive as hundreds of billions of ordinary
stars. At the centre of a black hole, space and time may be infinitely curved by
gravity. If you’re ever unlucky enough to be sucked in to one, your final
moments will be spent being stretched out like a piece of string – instant
spaghettification, or Bears new word.
![]() The Māori
Story
Knowledge: The Māori
creation story is based on observation and understanding of the Universe. This
ancient wisdom has many parallels with modern science: the seed of life at the
dawn of time, the separation of light from matter, and the ever-expanding
Universe.
![]() Potential: In the
beginning, there was lo-matua-kore – the first, the parentless, not knowing but
always there. In lo was the potential for everything in the
Universe.
![]() ![]() Becoming: Out of lo came
Te Kore, the void. Te Kore stirred and quickened, and the stars, Ngā Whetu, were
born. The stars brought forth darkness, Te Po, and light, Te Ao. Here, the
ancestral line divides. The long night gave birth to the earth mother,
Papatuānuku, and from the light, Ranginui the sky father emerged.
Atua: The children of
Rangi and Papa are atua, or gods – emanations of universal and physical life
forces. All things spring from them, including us. Atua – and we, their
descendants – are also Kaitaki, guardians of the natural world.
![]() The Long Night: Rangi and
Papa held each other in such a close embrace that no light could come into the
world. Their children were suffocated by darkness.
![]() The Separation: The atua
decided to free themselves by separating their parents. Tumatauenga began to
sever Rangi and Papa’s arms. But Tāne argued for a less cruel approach. He
braced his shoulders against his mother and pushed his parents apart with his
legs. For the first time, the children stood in the light – Te Ao
Mārama.
![]() Our World: Most of the
atua stayed with their mother, Papa. Tanaroa is the ocean, Tāne the forest, and
Ruaumoko – Papa’s unborn child – earthquakes and volcanoes. But Tāwhirimātea,
the winds, followed his estranged father into the sky and plagued his brothers
and sisters with gales and storms. The atua created the world we live in, its
living creatures – and us.
![]() Ritual of Retelling:
Every time the creation story is retold, the Universe is brought forth from the
void once more. There is no end to the story, because creation never stops
becoming. There is always a new generation waiting to add the next lines to the
story.
Whakapapa: For Moari,
cosmology is not only about explaining the Universe, but also about establishing
our place in it. That’s why it’s expressed in the form of whakapapa – genealogy.
There is no final distinction between people, the world that surrounds us, and
the Universe. Everything is related in an ancestry that stretches all the way
back to the parentless void, the origin of all things.
![]() Te Moananui-a-Kiwa – the
Pacific Ocean, is the world’s greatest ocean, bigger than all the continents put
together. For most of our history, the islands scattered across it were unknown
and uninhabited, beyond the reach of humanity. But a few thousand years ago –
long before other seafaring cultures dared venture out of the shallows – the
ancestors of the Polynesian people set out an epic migration across the Pacific,
using the stars, the Sun and the Moon as guides.
The Natural World:
Polynesian navigation was based on a holistic
understanding of the natural world. Every voyaging waka carried a tohunga tātai
arorangi – an expert in astronomy and navigation. By observing the marine
environment – birds feeding offshore; migrating whales; tides, winds and ocean
swells; the Sun by day and the stars overhead by night – the tohunga guided the
waka from island to island. Whales migrate from
their summer breeding grounds in the Pacific to feed in the Antarctic over
winter. Some Māori tribes describe how their ancestors came to Aotearoa on the
back of a whale – perhaps voyaging waka followed their migration paths.
Fairy terns and noddies are sea-birds that fly
out to sea by day and return to land at night. Seeing these ‘navigator birds’
feeding at sea was a sign that land was near.When
a voyaging waka nears an island, the long ocean swells are disrupted by waves
bouncing off the land. Cloud patterns also indicate the presence of land that is
beyond the horizon. Aotearoa is “the long white cloud”.
Māui: The stories of Māui
– the great hero, trickster and demi-god – are known right across the Pacific.
Many of them contain ancient navigational insights and knowledge. Māui’s fishing
up of land is about the ancient discoveries of new islands below the horizon.
The story of the taming of the Sun may be about human understanding of the
movements of the Sun and stars – which could then be ‘harnessed’ to make
exploration and voyaging possible.
![]() The Fishhook of Māui:
Māori legend tells how Māui used the sacred jawbone of Murirangawhenua, smeared
with his own blood, to fish up the North Island, Te Ika
a Māui – Māui’s fish. Māui’s fishhook, Te Matau a Māui – the tail of Scorpius,
is Aotearoa’s zenith constellation – at our latitude its highest point is
directly overhead. Red-glowing Rehua – Antares is said to be the blood Māui used
as bait.
![]() Te Waka o Tamarereti: One
day, Tamarereti sailed far out on the ocean. Reaching land, the exhausted
navigator fell asleep, waking at dusk to light a fire for cooking. As he gazed
deep into the flames, Tamarereti remembered his loved ones back home and was
filled with a passion to return. Tamarereti gathered the brightly glowing stones
from the fire and scattered them in the sky to guide his journey home. The sky
father, Ranginui, was so delighted with Tamarereti’s work that he placed his vessel - waka, in the sky. The stars the ancestors used
to navigate to Aotearoa trace the shape of Tamarereti’s waka in the night sky.
In the winter sky just before dawn, it lies along the horizon, anchored to the
south.
The Navigators: The
people of the Pacific settled nearly every inhabitable island in the vast ocean,
from Hawai’i far to the north to Aotearoa here in the south. They reached and
returned from South America at the ocean’s easternmost edge. Their achievements
are all the more amazing because they were accomplished without maps or
instruments. Instead, the navigators of these voyages relied on an extraordinary
knowledge of the movements of the Sun and the night skies through the seasons –
memorised over a lifetime of training and observation – and on their heightened
senses, fine-tuned to the ever-changing environment of the ocean
world.
![]() A Waka Renaissance: Much
of the knowledge of traditional navigational methods became incomplete or was
lost. But in some islands around the Pacific, the teachings were passed down
through the generations. In 1976, the Hokule’a – a twenty metre double hulled
canoe built by the Polynesian Voyaging Society – completed a return voyage from
Hawai’i to Tahiti under the guidance of Mua Piailug, a traditional navigator
from the Caroline Islands. The voyage of the Hokule’a was the beginning of a
waka renaissance, and a rediscovery of the ancient way-finding techniques.
Ben Finney described navigating aboard the
Hokule’a:- “Here we were sailing a double canoe across the dark ocean of the
third planet out from the Sun, steering on a succession of stars, one of which,
Alpha Centauri, is at 4.3 light years away – the closest star to our own – and a
moment later we were steering on a pair of external galaxies 179,000 and 210,000
light years away from us.”
![]() ALL IN ALL FASCINATING, SOME
THINGS CLEARER, SOME MORE
WOOLLY |