“Where do we come from? How did the universe begin? Why is the universe the way it is? How will it end?” These questions have baffled astrophysicists and mathematicians for centuries. We still have no clear explanation or evidence as to what our very purpose in this universe is. Hundreds of years ago, everyone believed that the Earth was at the center of the universe. Today we know better, but a complete picture of the universe remains elusive. From the ancient notion of a flat Earth to today’s theories on the very shape of past and future history, ideals of the universe have evolved with the help of scientific discovery and the eternal human imagination.
The History of our Universe
The most popular theory of our universe’s origin centers on a cosmic cataclysm unmatched in all of history— The Big Bang. This theory was born of the observation that other galaxies are moving away from our own at great speeds, in all directions, as if they had all been propelled by an ancient explosive force.
Before the big bang, scientists believe, the entire vastness of the observable universe, including all of its matter and radiation, was compressed into a hot, dense mass just a few millimeters across. This nearly incomprehensible state is theorized to have existed for just a fraction of the first second of time.
Big bang proponents suggest that some 10 billion to 20 billion years ago, a massive blast allowed all the universe’s known matter and energy—even space and time themselves—to spring from some ancient and unknown type of energy.
The theory maintains that, in the instant—a trillion-trillionth of a second—after the big bang, the universe expanded with incomprehensible speed from its pebble-size origin to astronomical scope. Expansion has apparently continued, but much more slowly, over the ensuing billions of years.
Scientists can’t be sure exactly how the universe evolved after the big bang. Many believe that as time passed and matter cooled, more diverse kinds of atoms began to form, and they eventually condensed into the stars and galaxies of our present universe.
The big bang theory leaves several major questions unanswered. One is the original cause of the big bang itself. Several answers have been proposed to address this fundamental question, but none has been proven—and even adequately testing them has proven to be a formidable challenge.
The Hubble Space Telescope:
The Hubble Space Telescope was designed to free astronomers of a limitation that has plagued them since the days of Galileo—Earth’s atmosphere. Shifting air pockets in the atmosphere block and distort light, limiting the view from even the most powerful Earth-bound instruments. Orbital telescopes function as eyes in the sky that allow astronomers to peer farther into the universe and see the cosmos more clearly.
Scientists began dreaming of such a telescope in the 1940s, but it took more than four decades for those dreams to become reality with the Hubble Space Telescope. The telescope’s original October 1986 launch was scrapped after the loss of the space shuttle Challenger. When the telescope finally became operational in 1990, it began to return unprecedented but flawed images. Its images were superior to those of Earth-bound instruments but slightly blurred due to an optical problem.
Hubble’s images have helped to pin down the age of the universe, which the expansion rate of pulsating stars suggests is some 13 billion to 14 billion years. Hubble has also captured images of many ancient galaxies, in all stages of evolution, and so lets scientists see back into the past days of a young and developing universe. The telescope was also instrumental in the discovery of dark energy, a little-known but ubiquitous force that works against gravity and contributes to the ongoing expansion of the universe. Hubble also measures the atmospheres of planets outside our own solar system, exploring their compositions and building data that could someday aid the search for extraterrestrial life.
Despite its many achievements, Hubble is likely nearing the end of its life. The telescope is due for its last periodic servicing in May 2009. Its successor, the James Webb Space Telescope, is scheduled for launch in 2013. The new instrument will orbit much farther from Earth (940,000 miles/1.5 million kilometers)—the better to peer farther through the dust of space into the earliest formations of stars, solar systems, and galaxies.
The Journey begins….
I have been an avid sky watcher since my young age. I am still fascinated by the very concept of the solar system, our presence in this cosmic universe and the fact that we have been able to evolve so much for thousands of years and have gained the propensity to think, ideate, contemplate theories, materialize our thoughts and perform path breaking experiments. Man is such an enigmatic creation of nature, just as enigmatic as the universe itself. We have developed technology to look beyond our imagination and see the beauty of the universe, the way it is supposed to be seen. We have traveled(visually) to the very depths of the universe and looked into the deepest of the galaxies. Yet, much remains to been seen and discovered as we slowly move towards the edge of what we might call ‘The Dawn of a new beginning’.
However, I shall keep my philosophical gibberish for another article and let us now travel to the very depths of space and begin to wonder at the mysteries as the universe unfold itself!
1) Hubble Sees ‘Island Universe’ in the Coma Cluster
A long-exposure Hubble Space Telescope image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light-years away in the northern constellation Coma Berenices.
2) A Galactic Spectacle
A beautiful new image of two colliding galaxies has been released by NASA’s Great Observatories. The Antennae galaxies, located about 62 million light-years from Earth, are shown in this composite image from the Chandra X-ray Observatory (blue), the Hubble Space Telescope (gold and brown), and the Spitzer Space Telescope (red). The Antennae galaxies take their name from the long antenna-like “arms,” seen in wide-angle views of the system. These features were produced by tidal forces generated in the collision.
3) Great Ball of Fire
On August 1, 2010, almost the entire Earth-facing side of the sun erupted in a tumult of activity. This image from the Solar Dynamics Observatory of the news-making solar event on August 1 shows the C3-class solar flare (white area on upper left), a solar tsunami (wave-like structure, upper right), multiple filaments of magnetism lifting off the stellar surface, large-scale shaking of the solar corona, radio bursts, a coronal mass ejection and more.
4) The Blue Marble
View of the Earth as seen by the Apollo 17 crew traveling toward the moon. This translunar coast photograph extends from the Mediterranean Sea area to the Antarctica south polar ice cap. This is the first time the Apollo trajectory made it possible to photograph the south polar ice cap. Note the heavy cloud cover in the Southern Hemisphere. Almost the entire coastline of Africa is clearly visible. The Arabian Peninsula can be seen at the northeastern edge of Africa. The large island off the coast of Africa is Madagascar. The Asian mainland is on the horizon toward the northeast.
5) Hubble Snaps Sharp Image Of Cosmic Concoction
A colourful star-forming region is featured in this stunning new NASA/ESA Hubble Space Telescope image of NGC 2467. Looking like a roiling cauldron of some exotic cosmic brew, huge clouds of gas and dust are sprinkled with bright blue hot young stars.
6) Starburst Cluster Shows Celestial Fireworks
Like a celebration fireworks display a young, glittering collection of stars looks like an aerial burst. The cluster is surrounded by clouds of interstellar gas and dust – the raw material for new star formation. The nebula, located 20,000 light-years away in the constellation Carina, contains a central cluster of huge, hot stars.
7) Cassiopeia A supernova
Images from NASA’s Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe’s most energetic particles — cosmic rays.
8 ) Hubble Captures Spectacular “Landscape” in the Carina Nebula
NASA’s Hubble Space Telescope captured this billowing cloud of cold interstellar gas and dust rising from a tempestuous stellar nursery located in the Carina Nebula, 7,500 light-years away in the southern constellation Carina. This pillar of dust and gas serves as an incubator for new stars and is teeming with new star-forming activity.
9) Image of Carina Nebula
This Hubble photo is of a small portion of one of the largest seen star-birth regions in the galaxy, the Carina Nebula. Towers of cool hydrogen laced with dust rise from the wall of the nebula. The scene is reminiscent of Hubble’s classic “Pillars of Creation” photo from 1995, but is even more striking in appearance. The image captures the top of a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars. The pillar is also being pushed apart from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks like arrows sailing through the air.
10) Solar Eruption and a Flare
An image after a solar eruption and a flare. The dark regions show the site of evacuated material from the eruption, and the large magnetic loops were formed during the flare.
11) Sun’s surface
This close-up image of a filament and active region, taken in extreme UV light, shows a dark and elongated filament hovering above the Sun’s surface (May 18, 2010). The bright regions beneath it, which show where heating is going on in the magnetic field, send up shafts of plasma that trace magnetic field lines emerging from them. Filaments are cooler clouds of gas that are suspended by tenuous magnetic fields. They are often unstable and commonly erupt. This one is estimated to be at least 60 Earth diameters long (about 500,000 miles).
12) Barred Spiral Galaxy NGC 1300
The Hubble telescope has captured a display of starlight, glowing gas, and silhouetted dark clouds of interstellar dust in this grand image of the barred spiral galaxy NGC 1300. NGC 1300 is considered to be prototypical of barred spiral galaxies. Barred spirals differ from normal spiral galaxies in that the arms of the galaxy do not spiral all the way into the center, but are connected to the two ends of a straight bar of stars containing the nucleus at its center.
13) The Sun
The STEREO spacecraft caught this spectacular eruptive prominence in extreme UV light as it blasted away from the Sun (Apr. 12-13, 2010). This was certainly among the largest prominence eruptions ever seen. The length of the prominence appears to stretch almost halfway across the sun, about 500,000 miles. Prominences are cooler clouds of plasma that hover above the Sun’s surface, tethered by magnetic forces. They are notoriously unstable and commonly erupt as this one did in a dramatic fashion.
14) Andromeda Galaxy: Insights on White Dwarfs
This composite image of M31 (also known as the Andromeda galaxy) shows X-ray data from NASA’s Chandra X-ray Observatory in gold, optical data from the Digitized Sky Survey in light blue and infrared data from the Spitzer Space Telescope in red. The Chandra data covers only the central region of M31 as shown in the inset box for the image.
15) Eagle Nebula M16
The soaring tower is 9.5 light-years or about 57 trillion miles high, about twice the distance from our Sun to the next nearest star. Stars in the Eagle Nebula are born in clouds of cold hydrogen gas that reside in chaotic neighborhoods, where energy from young stars sculpts fantasy-like landscapes in the gas. The tower may be a giant incubator for those newborn stars. A torrent of ultraviolet light from a band of massive, hot, young stars is eroding the pillar.
16) Infrared image of the core of the Milky Way Galaxy
The Milky Way Galaxy, commonly referred to as just the Milky Way, or sometimes simply as the Galaxy, is the galaxy in which our Solar System is located. The Milky Way is a barred spiral galaxy that is part of the Local Group of galaxies. It is one of billions of galaxies in the observable universe. Its name is a translation of the Latin Via Lactea, in turn translated from the Greek Γαλαξίας (Galaxias), referring to the pale band of light formed by stars in the galactic plane as seen from Earth
17) Image of the spiral galaxy Messier 101
The red color shows Spitzer’s view in infrared light. It highlights the heat emitted by dust lanes in the galaxy where stars can form. The yellow color is Hubble’s view in visible light. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes.The blue color shows Chandra’s view in X-ray light. Sources of X-rays include million-degree gas, exploded stars, and material colliding around black holes.
18) NGC 4013
NGC 4013 is a spiral galaxy, similar to our own Milky Way, lying some 55 million light-years from Earth in the direction of the constellation Ursa Major. Viewed pole-on, it would look like a nearly circular pinwheel, but NGC 4013 happens to be seen edge-on from our vantage point. Even at 55 million light-years, the galaxy is larger than Hubble’s field of view, and the image shows only a little more than half of the object, albeit with unprecedented detail.
19) Supernova Remnant Simeis 147
Simeis 147 (a.k.a. Sharpless 2-140) is the remant of a very old supernova straddling the border of Taurus and Auriga. The shell of expanding gas has expanded to huge proportions — over 3.5 degrees wide, or more than 7 full moons wide. Due to its huge size and age, it is also extremely faint and challenging to image. This is a mosaic of two frames showing the southern portion of it.
20) The Rosette Nebula
The Rosette Nebula is a very bright and very large emission complex in the constellation of Monoceres. The open cluster contains many hot young stars whose stellar winds are slowly hollowing out the nebula. The Rosette is nearly 2° in size and is easily found in just about any amateur telescope.
21) Swan Nebula : A perfect storm of turbulent gases
Like the fury of a raging sea, this anniversary image from the NASA Hubble Space Telescope shows a bubbly ocean of glowing hydrogen, oxygen, and sulphur gas in the extremely massive and luminous molecular nebula Messier 17. This Hubble photograph captures a small region within Messier 17 (M17), a hotbed of star formation. M17, also known as the Omega or Swan Nebula, is located about 5500 light-years away in the Sagittarius constellation.
22) Red Spider Nebula
Huge waves are sculpted in this two-lobed nebula some 3000 light-years away in the constellation of Sagittarius. This warm planetary nebula harbours one of the hottest stars known and its powerful stellar winds generate waves 100 billion kilometres high. The waves are caused by supersonic shocks, formed when the local gas is compressed and heated in front of the rapidly expanding lobes. The atoms caught in the shock emit the spectacular radiation seen in this image.
23) Heart of the Whirlpool Galaxy
New images from NASA’s Hubble Space Telescope are helping researchers view in unprecedented detail the spiral arms and dust clouds of a nearby galaxy, which are the birth sites of massive and luminous stars.
The Whirlpool galaxy, M51, has been one of the most photogenic galaxies in amateur and professional astronomy. Easily photographed and viewed by smaller telescopes, this celestial beauty is studied extensively in a range of wavelengths by large ground- and space-based observatories. This Hubble composite image shows visible starlight as well as light from the emission of glowing hydrogen, which is associated with the most luminous young stars in the spiral arms.
24) Cone Nebula :Hubble images ghostly star-forming pillar of gas and dust
Resembling a nightmarish beast rearing its head from a crimson sea, this celestial object is actually just a pillar of gas and dust. Called the Cone Nebula (in NGC 2264) – so named because in ground-based images it has a conical shape – this monstrous pillar resides in a turbulent star-forming region. This picture, taken by the newly installed Advanced Camera for Surveys (ACS) aboard the NASA/ESA Hubble Space Telescope, shows the upper 2.5 light-years of the Cone, a height that equals 23 million roundtrips to the Moon. The entire pillar is seven light-years long.
25) The Boomerang Nebula – the coolest place in the Universe?
The Boomerang Nebula is a young planetary nebula and the coldest object found in the Universe so far. The NASA/ESA Hubble Space Telescope image is yet another example of how Hubble’s sharp eye reveals surprising details in celestial objects.
This NASA/ESA Hubble Space Telescope image shows a young planetary nebula known (rather curiously) as the Boomerang Nebula. It is in the constellation of Centaurus, 5000 light-years from Earth. Planetary nebulae form around a bright, central star when it expels gas in the last stages of its life.
26) Eagle Nebula Details: Pillars of Creation
Undersea corral? Enchanted castles? Space serpents? These eerie, dark pillar-like structures are actually columns of cool interstellar hydrogen gas and dust that are also incubators for new stars. The pillars protrude from the interior wall of a dark molecular cloud like stalagmites from the floor of a cavern. They are part of the “Eagle Nebula” (also called M16), a nearby star-forming region 6,500 light-years away in the constellation Serpens.
27) Ring Nebula
The NASA Hubble Space Telescope captured the sharpest view yet of the most famous of all planetary nebulae: the Ring Nebula (M57). In this October 1998 image, the telescope looked down a barrel of gas cast off by a dying star thousands of years ago. This photo reveals elongated dark clumps of material embedded in the gas at the edge of the nebula; the dying central star floating in a blue haze of hot gas. The nebula is about a light-year in diameter and is located some 2,000 light-years from Earth in the direction of the constellation Lyra.
28) Carina Nebula Details: Keyhole Nebula
Previously unseen details of a mysterious, complex structure within the Carina Nebula (NGC 3372) are revealed by this image of the ‘Keyhole Nebula, ‘ obtained with the Hubble Space Telescope. The picture is a montage assembled from four different April 1999 telescope pointings with Hubble’s Wide Field Planetary Camera 2, which used six different colour filters. The picture is dominated by a large, approximately circular feature, which is part of the Keyhole Nebula, named in the 19th century by Sir John Herschel. The Carina Nebula also contains several other stars that are among the hottest and most massive known, each about 10 times as hot, and 100 times as massive, as our Sun.
29) Hubble images remarkable double cluster
Located in the Large Magellanic Cloud, one of our neighbouring dwarf galaxies, this young globular-like star cluster is surrounded by a pattern of filamentary nebulosity that is thought to have been created during supernova blasts. It consists of a main globular cluster in the centre and a younger, smaller cluster, seen below and to the right, composed of extremely hot, blue stars and fainter, red T-Tauri stars. This wide variety of stars allows a thorough study of star formation processes
30) Hubble Mosaic of the Majestic Sombrero Galaxy
NASA/ESA Hubble Space Telescope has trained its razor-sharp eye on one of the universe’s most stately and photogenic galaxies, the Sombrero galaxy, Messier 104 (M104). The galaxy’s hallmark is a brilliant white, bulbous core encircled by the thick dust lanes comprising the spiral structure of the galaxy. As seen from Earth, the galaxy is tilted nearly edge-on. We view it from just six degrees north of its equatorial plane. This brilliant galaxy was named the Sombrero because of its resemblance to the broad rim and high-topped Mexican hat.
31) Hubble Spies Cosmic Dust Bunnies
Like dust bunnies that lurk in corners and under beds, surprisingly complex loops and blobs of cosmic dust lie hidden in the giant elliptical galaxy NGC 1316. This image made from data obtained with the NASA/ESA Hubble Space Telescope reveals the dust lanes and star clusters of this giant galaxy that give evidence that it was formed from a past merger of two gas-rich galaxies.
32) Hubble’s most detailed image of the Crab Nebula
This Hubble image – One among the largest ever produced with the Earth-orbiting observatory – shows gives the most detailed view so far of the entire Crab Nebula ever made. The Crab is arguably the single most interesting object, as well as one of the most studied, in all of astronomy. The image is the largest image ever taken with Hubble’s workhorse camera.
33) V838 Monocerotis
Light continues to echo three years after stellar outburst. The Hubble Space Telescope’s latest image of the star V838 Monocerotis (V838 Mon) reveals dramatic changes in the illumination of surrounding dusty cloud structures. The effect, called a light echo, has been unveiling never-before-seen dust patterns ever since the star suddenly brightened for several weeks in early 2002.
34) NGC 346
Young stars sculpt gas with powerful outflows. This Hubble Space Telescope view shows one of the most dynamic and intricately detailed star-forming regions in space, located 210,000 light-years away in the Small Magellanic Cloud (SMC), a satellite galaxy of our Milky Way. At the centre of the region is a brilliant star cluster called NGC 346. A dramatic structure of arched, ragged filaments with a distinct ridge surrounds the cluster.
35) The Flame Nebula
The Flame nebula is an emission nebula in the constellation Orion. It is about 900 to 1,500 light-years away. The bright star Alnitak (ζ Ori), the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame and this knocks electrons away from the great clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. Additional dark gas and dust lies in front of the bright part of the nebula and this is what causes the dark network that appears in the center of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula.
36) Omega Nebula
The Omega Nebula is between 5,000 and 6,000 light-years from Earth and it spans some 15 light-years in diameter. The cloud of interstellar matter of which this nebula is a part is roughly 40 light-years in diameter. The total mass of the Omega Nebula is an estimated 800 solar masses. A open cluster of 35 stars lies embedded in the nebulosity and causes the gases of the nebula to shine due to radiation from these hot, young stars.
37) Cat’s Eye Nebula
The Cat’s Eye Nebula (NGC 6543) is a planetary nebula in the constellation of Draco. Structurally, it is one of the most complex nebulae known, with high-resolution Hubble Space Telescope observations revealing remarkable structures such as knots, jets, bubbles and sinewy arc-like features. In the center of the Cat’s Eye there is a bright and hot star, which around 1000 years ago lost its outer envelope producing the nebula.
38) Horse head Nebula
The Horsehead Nebula is approximately 1500 light years from Earth. It is one of the most identifiable nebulae because of the shape of its swirling cloud of dark dust and gases, which is similar to that of a horse’s head when viewed from Earth.
The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead’s neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright spots in the Horsehead Nebula’s base are young stars just in the process of forming.
39) Liberating Star
This is a composite image of the SN 1006 supernova remnant, which is located about 7000 light years from Earth. Shown here are X-ray data from NASA’s Chandra X-ray Observatory (blue), optical data from the University of Michigan’s 0.9 meter Curtis Schmidt telescope at the NSF’s Cerro Tololo Inter-American Observatory (CTIO; yellow) and the Digitized Sky Survey (orange and light blue), plus radio data from the NRAO’s Very Large Array and Green Bank Telescope
40) Aurora Australis
Aurora Australis is featured in this image photographed by an Expedition 23 crew member on the International Space Station. Among the views of Earth afforded crew members aboard the ISS, surely one of the most spectacular is of the aurora. These ever-shifting displays of colored ribbons, curtains, rays, and spots are most visible near the North (Aurora Borealis) and South (Aurora Australis) Poles as charged particles streaming from the sun (the solar wind) interact with Earth’s magnetic field, resulting in collisions with atoms of oxygen and nitrogen in the upper atmosphere.
Epilogue:
Let me, in this closing paragraphs, consider where our rapidly accumulating store of knowledge about the universe is leading us. That it provides satisfaction to a host of curiosity-motivated physicists and astronomers is beyond dispute. However, some view it as a humbling experience in that each increase in knowledge seems to reveal more clearly our own relative insignificance in the grand scheme of things.
Where do we come from? How did the universe begin? Why is the universe the way it is? How will it end?
“All my life, I have been fascinated by the big questions that face us, and have tried to find scientific answers to them. If, like me, you have looked at the stars, and tried to make sense of what you see, you too have started to wonder what makes the universe exist. The questions are clear, and deceptively simple. But the answers have always seemed well beyond our reach. Until now.
The ideas which had grown over two thousand years of observation have had to be radically revised. In less than a hundred years, we have found a new way to think of ourselves. From sitting at the center of the universe, we now find ourselves orbiting an average-sized sun, which is just one of millions of stars in our own Milky Way galaxy. And our galaxy itself is just one of billions of galaxies, in a universe that is infinite and expanding. But this is far from the end of a long history of inquiry. Huge questions remain to be answered, before we can hope to have a complete picture of the universe we live in.
“I want you to share my excitement at the discoveries, past and present, which have revolutionized the way we think. From the Big Bang to black holes, from dark matter to a possible Big Crunch, our image of the universe today is full of strange sounding ideas, and remarkable truths. The story of how we arrived at this picture is the story of learning to understand what we see.”
-STEPHEN HAWKING
Although our position in the universe may be insignificant, the laws of Physics that we have discovered (uncovered?) seem to hold throughout that universe — as far as we know — since the universe began and for all future time. Ar least there is no evidence that other laws hold in other parts of the universe. Thus, until someone complains, we are entitled to stamp the laws of Physics “Discovered on Earth”. Much remains to be discovered :
“The universe is full of magical things, patiently waiting for our wits to grow sharper.”
Sources and Further Inspiration:
1) National Geo – Science and Space
2) Stephen Hawking’s Universe
3) 20 years of Hubble History under the Telescope
4) Astronomy Picture of the day – Archive
5) Hubble Site – All the Hubble news and pictures
6) Web – 18 : Breathtaking Space Photography
7) Astrophysics Pool on Flickr
