Backyard Voyages
Exploring picture postcards from lost times.
"The real voyage of discovery consists not in seeking new landscapes, but in having new eyes." - Marcel Proust
Saturday, November 2, 2024
ATLAS Shrugged
Sunday, September 22, 2024
In the Lair of a Lagoon
Wide angle view of Trifid and Lagoon Nebulae, Sep 20, 2024. Photo credit: Purnendu Gupta |
The Lagoon nebula is a popular late-summer / early fall target for stargazers in the northern hemisphere. Perched above the tipped "teapot" of Sagittarius it disappears below the horizon quickly in the following months. By that measure, this Friday, September 20th, two days before the official start of fall, was past its prime viewing window. Yet, I chose to give it a shot.
The result was the image above. A two-for-one wide angle view of two nebulae, the Trifid on the left and the Lagoon on the right. Light that is more than four thousand years old, gathered over 52 minutes through a narrowband filter. The image is rich in red Hydrogen-alpha light which is the signature of emission nebulae. To me, the swirling clouds around a brighter core of the Lagoon looks like the whorls in rose petals. The nearby Trifid has menacing dark streaks across its face. Unfettered by such features, the Lagoon might appear to be a calmer place. Yet, nothing could be farther from the truth.
Sunday, May 12, 2024
The Goddess of Dawn
Aurora in New Jersey, May 11, 2024 |
The word "Aurora" comes from Latin. In Roman mythology and Latin poetry it is the name of the goddess of dawn. It was first used by Gallileo in the context of the atmospheric phenomemon. The word pairs “Aurora Borealis”, or “Northern Lights”, conjures up imagery of colorful, curled flows of light tucked away in the high northern latitudes, somewhere in the Nordics or Iceland. Rarely does this phenomenon descend from the earth's poles to the lower latitudes. In the contiental United States, that means it does not extend beyond northern states like Minnesota or Alaska. Viewing the Northern lights has been on the bucket list of low latitiude dwellers like myself.
Spring of 2024, May 11th was one of those very rare occassions when the "goddess of dawn" visited us right here in my New Jersey backyard at the lowly 40 degrees north latitude.
Wednesday, May 1, 2024
Fireflies
Watch closely.
Those little pools - of light.
Take away their names,
And they become a swarm
Of fireflies.
Monday, April 8, 2024
Mooned!
A Seven Year Wait
Taming The Digital Wolves
Location location location
Verity in Vermont
And then, all that remained was a black hole in the sky.
and for what will be the last time in the next 20 years in America, a cloudless mid-day had turned into night.
Friday, February 9, 2024
Into A Sea of Stars
The Universe That Wasn’t There
Growing up in a big city almost anywhere in the world breeds a certain disinterest in the sky.
Observing stars in the night sky just isn't something big city people do, or fill any part of their busy lives thinking about. So for most of my childhood, which was in a corner of big city, I never really developed a feel for the the night sky. There was a bookish understanding of stuff up there. Planets were things that existed in text books. The sun moved between imaginary lines of tropics in diagrams of geography lessons. A school teacher once mentioned that সপ্তর্ষি মণ্ডল (the Bengali name for the Big Dipper in the Indian sky culture) was a constellation which looked like a question mark if one looked north at the dead of the night. I only had a vague idea of where "north" was - thanks to a tiny little compass tucked away in a drawer in my grandfather's writing desk. We lived in a bungalow style home wth an open terrace. During warm summer nights, especially with power cuts which were frequent then, my parents and I sometimes went up there to catch a cool breeze. I have vague memories of seeing the moon. But trying to find a constellation at an unearthly hour was an adventure too far. I had no idea where or how to begin. Then there was in a monthly magazine a series titled কালপুরুষ ("Kalpurush") authored by a famous writer of the time. The title stood out as strange, mysterious and memorable in an awkward way. It literally translated to "temporal man". Though I had no idea what it really was about. I would later learn in the vedic constellation nomenclature, the name was a reference to Orion the hunter. But for that time, the universe lay perfectly hidden behind the everyday things we did in the pursuit of happiness.
Temporal Man
In the four decades that passed, my own pursuits took me to major cities in India (Delhi and Mumbai) and thereafter to the United States. And eventually I had the good fortune of moving to the suburbs of New Jersey where light pollution had not fully enveloped the night skies and life at night was not a mad rush to get ready for the next day of work. With books, and then phone apps as a guide, I slowly taught myself how to read the night sky. Armed with a digital SLR camera that I already had and a pair of astronomy binoculars which I bought, I started my journey into the world of backyard astronomy and astrophotography. These modest tools would become my magic wands to lift the veil of darkness. And one of my first adventures would involve chasing Orion.
Into a Sea of Stars
Somewhere between then and now, ten years had passed and my flirtations with the hobby had grown into a steady affair. This night in 2024, was a chilly February night with a few wispy clouds. I opened my front door for a "check in" on the universe before retiring for the night. Centered on the vaulted arch of my doorway was this starry humanoid figure majestically towering above me. Orion the hunter, It was by now a very familiar friend. Betelgeuse on its left shoulder, was visibly ruddy, as was Aldebaran, the eye of Taurus to the far right. There was also no mistaking Sirius the dog-star at its left foot. The bright "eye" aside - I could see the whole Canis Major constellation down to the dog’s tail. In my mind, for a moment every vestige of human settlement below faded away. I felt like I could take a step forward from the threshold of my home and dip into a sea or stars.
Hello Darkness
I had to pause to take a picture. This was a single shot with an SLR on a tripod. I threw in a clip-in light pollution filter to suppress the amber glow of sodium-vapor street lamps. A few tries later - I landed on this single 20 second exposure that did the trick. And after a little abracadabra on the computer - it was just perfect. Only in hindsight I realized that ten years after my first rendezvous, I had come a full circle standing face to face with the timeless “Temporal Man” again.
From being blind to a whole universe that lies hidden in plain sight, to being able to open the front door and step into a sea of stars - many of which I know by name - has been a long and rewarding journey into realms I did not imagine existed. And for that, I shall remain eternally grateful to life.
Friday, December 15, 2023
It's Raining Gems
While most major meteor showers originate from comets, the Geminids are among a few believed to originate from an asteroid. The source is the object called 3200 Phaethon. It is known as a "rock comet" since it had a trajectory like a comet but had no tail . The object was discovered by famous American Astronomer Fred Whipple who realized the object was connected to the meteor shower. Due to its close approach to the Sun, Phaethon is named after the character of Greek myth who drove the Sun-god Helios' chariot. 3200 Phaethon was discovered on Oct. 11, 1983, by the Infrared Astronomical Satellite..
A Geminid in Orion
My 2023 Geminid imaging setup included a DSLR mounted on a start tracker and set up for 3 nights in a row in my backyard with a self timer attached. Despite one lost day to a false start, the resulting composite shows seven Geminid meteors imaged over the nights of Dec 13th to 15th, 2023. The imaging duration spans the predicted peak night of Geminids in 2023.The image on the left is a crop from the image above. This frames up a single Geminid meteor streaking across the constellation of Orion. It originated near Betelgeuse and travelled past the easternmost belt star, Mintaka.
All images were taken using a stock Canon 70D DSLR on a tracked mount with a 11 mm ultra wide lens at its widest setting, ISO 800 and 10s exposure. No filters were used.
composite showing seven Geminid meteors imaged over the nights of Dec 13th to 15th, 2023. The imaging duration spans the predicted peak night of Geminids in 2023.
Thursday, September 21, 2023
Last Sunset: The Final Bloom
Helix Nebula (Eye of God). Credit: Purnendu Gupta |
End of Days
Where do stars like the sun go when they die? At five billion years old, our sun is a middle aged star. It is also a middle class star, in the stellar spectral classification (yellow G type). When stars of this type reach the end of life, they do what humans do at the end of their working lives. They retire.
That’s right. They do not explode into a supernova like their big brothers, or collapse into black holes like their superstar cousins. They gently walk into ... the sunset. And when they do, they leave behind what is known as a planetary nebula like the one you see in the image above. The Helix Nebula is also known as the Eye of God, for its unique shape. The nearest example of its kind, it is at about 650 light years distant in the constellation of Aquarius. The image above was shot from my backyard in November of 2022 and is light gathered over an hour and a quarter. The image below is a false-color composite of the same, in visible and invisible “light” as seen by four special purpose NASA telescopes that see in different wavelengths.
Helix Nebula, Composite X-Ray, UV, Optical, Infra Red Source: Nasa |
Stars are nuclear fusion reactors that exist at a self adjusting balance between the inward pull of gravity and the outward pressure of hot fusing matter. A little bit like a balloon that exists at the sweet spot between the squishing pull of its skin, and the swelling push of the air inside.
A star first lights up when fusion is triggered in the core of the proto-star, among the simplest atom of all - primordial Hydrogen that have atomic number one. This is forced by enormous gravity to combine with its neighbor transforming into the next heavier element in the Periodic Table, Helium, with atomic number two. As all hydrogen is exhausted, three of these Helium atoms will combine to form Carbon with atomic number six and so on. The nuclear alchemy goes on to magically cook heavier elements from lighter ones releasing energy in the process.
About 12,000 years ago, the progenitor star of the Helix nebula started to run out of its hydrogen fuel. The star cooled some and lost some of its ability to hold itself up against gravity. The core shrank, and the outer layers slipped away from its grip into space cooling and expanding into a red giant. This was the end of the “middle class sun” phase of life of the star. Any planets in that solar system experienced the last sunset as the shell of expelled gas engulfed the inner planets just as our own sun would engulf Mercury, Venus and possibly the Earth.
The Star Within a Star
Once the outer veil got lifted what lay exposed was the star's stopped nuclear engine. While no longer undergoing fusion, it is held up by another force known as electron degeneracy pressure. A bright core made mostly of a soup of electrons, carbon nuclei and some other elements, on its way to becoming a white hot midget star - a white dwarf.
A white dwarf contains about half the mass of the original star but is compressed by gravity into a ball merely the size of the earth or only 1/100th of the sun’s original diameter. As a result the densities are enormous. A tea spoon could weigh as much as an average car on earth. For comparison, a spoon ful of the sun’s core would be much lighter at only 750 grams.
By the time the white dwarf forms, the expelled shell has not had time to go very far - and is perhaps a light year or two away from the core. Instead of being a perfect sphere, the expanding shell takes on beautiful shapes due to pre-existing asymmetries. The radiation from the white dwarf core lights up the expanding gas in concentric shells of colors. The Hydrogen glows red and the Oxygen glows blue and green. Like a cosmic flower in final bloom. While the “retired” white dwarf will last many tens of billions of years, the shells of the nebula around it will quickly fade away.
Forget Me Knots
In 1996, a closer look into the Helix through the Hubble Space Telescope revealed some knot like structures, that were observed to lie in a ring pattern within the outer shell. These appear to be comet-like with a head and a tail pointing radially away from the core of the system. First discovered in the Helix, they were later found in many planetary nebulae. These knots were found to be the size of our solar system formed as the surrounding lighter gas got eroded and stripped back by the stellar wind and radiation from the central white dwarf forming finger like shapes due to a phenomenon known as the Rayleigh-Taylor instability.
There are some theories that suggest that the origin of these knots may result from interactions of the progenitor star with its binary partner. But since the shell is only a couple of light years in diameter wide, the distances are perhaps too small for typical two star systems. Yet another theory suggests these could be remains of supersized comets the size of planets - the likes of which have not been seen before. A more likely explanation may have to do with remains of large planets that orbited the original star. As the star expanded to a red giant, these bodies may have continued to orbit "inside" the parent star. Over thousands of years, as the stellar wind and radiation from the white dwarf stripped away the lighter gas, all that remained are these comet like streams with the "tails" like little flags of existence.Was there life on any of these worlds? Evolution that spanned millions of years and civilizations that thrived for millennia? If so, these cometary knots may be the only signs that they were ever here.
Imaging Specs:
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25x180s light frames (total 1 h 15 min integration) with calibration frames. Optolong L-enhance narrowband filter. ASI294MC Pro cooled camera. Guided exposure with Celestron 127 SLT Mak-Cass on AVX mount
References:
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The Hubble Helix Observations from stsci.edu
Cometary Knots in the Helix Nebula by O'Dell, C. R. & Handron, K. D., from Astronomical Journal, April 1996
A "FIREWORK" OF H2 KNOTS IN THE PLANETARY NEBULA NGC 7293 (THE HELIX NEBULA) by M. Matsuura et al., from the Astrophysical Journal Published 2009 July 8Further Reading:
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White Dwarf Star from Britannica.
Iridescent Glory of Nearby Planetary Nebula Showcased on Astronomy Day from Hubblesite
HubbleMinute: Helix Nebula from Hubblesite (Video)
Wednesday, July 5, 2023
Ice Age Minds: The First Constellation
Taurus and Pleiades hang low on the western skies. Seen from my backyard in March, 2023 |
19,000 Years Ago
The darkness in the cave, was near perfect. In a little pool of light made by the faint glow of a tallow lamp, stood a man. In his hand was a piece of charcoal. His weathered fingers scratched the charcoal against the cave wall repeating strokes that created the outlines of the neck of an animal. Slowly, in the flicker of the lamp, the shape of a bull began to emerge. The horns, the eye, the hump. The air was filled with the odor of burning animal fat and strange sounds of men working on similar imagery. The distant sound of underground flowing water echoed through the cavernous tunnels some 50 feet underground - in Lascaux Caves, near the village of Montignac, modern day France.
Some nineteen thousand years before present day, this would have been the creation scene of one of the most famous examples of upper paleolithic art. Other panels depicting larger than life imagery of horses, deer, bisons, birds and humans that decorated the walls have fascinated researchers since their serendipitous discovery in 1940s. The artistic sophistication of these works from our ancestors rendered in charcoal and ochre have intrigued men. But even among this unique collection of ancient figures, bull number four in the Hall of the Bulls stands out. On the back of the animal, there are six dots that look remarkably like a familiar shape in the night sky. The asterism Pleiades that is visible to the naked eye from all parts of the world. Placed above the hump of the bull it completes the picture of the star field in the modern constellation of Taurus.
Bull No. 4, Hall of Bulls, Lascaux, France |
Ice Age Star Maps?
However a few researchers have proposed that the cave paintings were not just art but the most ancient star maps made by man. German researcher Dr. Michael Rappenglueck, of the University of Munich is the foremost among the proponents of this theory. According to him "It is a map of the prehistoric cosmos," ... "It was their sky, full of animals and spirit guides". In fact similar star maps have been discovered in ancient cave art in Spain, in Cueva di El Castillo cave, in the mountains of Pico del Castillo Dr. Rappenglueck has identified more constellations such as the Northern Crown. Many agree his findings and postulates are reasonable.
So what was going on in the minds of these ancient artists of the ice age? Were the caves spiritual places like temples? Or were they planetariums of sorts? Regardless of purpose, these ancient caves left their first explorers enthralled by a profound experience of reaching across time. In the words of the first explorers the Chauvet Cave in Ardeche France:
"...Alone in that vastness, lit by the feeble beam of our lamps, we were seized by a strange feeling. Everything was so beautiful, so fresh, almost too much so. Time was abolished, as if the tens of thousands of years that separated us from the producers of these paintings no longer existed. ... Deeply impressed, we were weighed down by the feeling that we were not alone; the artists souls and spirits surrounded us..."We may never fully know their minds. But if these were indeed star maps, and since constellations are figments of human imagination, bull number 4, in the Hall of the Bulls in Lascaux, may well have been Taurus, the first constellation to be ever recorded in the history of mankind. And today when we stand in our backyards and gaze at these enormous figures in the sky - we may feel a sense of kinship with early humans that once walked the earth..
Reference
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Ice Age star map discovered from BBC March, 2000
Sunday, May 28, 2023
From Nova to Naught
Lady Luck called. But I wasn’t ready.
In fact I didn’t even recognize her since just as Thomas Edison predicted, she looked like work, dressed in overalls.
On May 19, at 2 a.m. from my New Jersey backyard, I was testing my telescope tracking on an object I have never imaged before. The Pinwheel galaxy (Messier 101). The next day I heard that the 75 year old supernova hunter extraordinaire, Koichi Itagaki had done it again. Beating research grade observatories to the punch, he had reported a supernova in the same galaxy that very night.
I went back to check my images, and sure enough, amidst the wispy arms of the spiral, a new dot had appeared. An exploding star that outshone all its peers 21 million light years away. I had imaged a new supernovae only once before, a month after its discovery. But this time it was different. My time of capture was BEFORE that of Itagaki. More than 9 hours ahead.
“So you discovered it too.” My nine year old quipped, eyes slightly wider.
“Nope.” I said. “Whoever reports it first gets credit.”
On a website that tracks these, there are 8 confirmed reports of others around the world who have reported imaging this pre-discovery, me included. None of them, was as prepared as Itagaki to confirm it’s appearance.
So, what’s the lesson?
Firstly be prepared. Second - when you see a lady in overalls, look again.
Else it may just be your chance of a lifetime coming to naught.
http://www.rochesterastronomy.org/sn2023/sn2023ixf.html
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Further Reading: