Category Geology

What are the oldest surviving photographs of moon?

In March 1840, English-born American John William Draper clicked what are now the oldest surviving photographs of the moon. Using the daguerreotype process that had just been invented, Draper clicked the photograph that showed lunar features.

The smartphones in our hands these days are so powerful and equipped with great cameras that all we need to do to click a photograph of the moon is to wait for the moon to make its appearance and then take a photograph. It wasn't always this easy though. In fact, the oldest surviving photographs of the moon are less than 200 years old. The credit for taking those photographs goes to English-born American scientist, philosopher, physician, chemist, historian and photographer John William Draper.

 Born in England in 1811, Draper went to the U.S. in 1832. After receiving a medical degree from the University of Pennsylvania, he moved to New York University in 1837 and was one of the founders of NYU’s School of Medicine in 1840. He not only taught there for most of his life, but also served as the president of the med school for 23 years.

Learns Daguerre's process

 His interest in medicine, however, didn't keep him away from dabbling with chemistry too. The chemistry of light-sensitive materials fascinated Draper and he learned about the daguerreotype process of photography after the news arrived in the U.S. from Europe. French artist and photographer Louis Daguerre had invented the process only in 1839.

Draper attempted to improve the photographic process of Daguerre and succeeded in ways to increase plate sensitivity and reduce exposure times. These advances not only allowed him to produce some of the best portrait photographs of the time, but also let him peer into the skies to try and capture the moon.

He met with failure in his first attempts over the winter of 1839-40. He tried to make daguerreotypes of the moon from his rooftop observatory at NYU, but like Daguerre before him, was unsuccessful. The images produced were either underexposed, or were mere blobs of light in a murky background at best.

Birth of astrophotography

 By springtime in March 1840, however, Draper was successful, thereby becoming the first person ever to produce photographs of an astronomical object. He was confident enough to announce the birth of astrophotography to the New York Lyceum of Natural History, which later became the Academy of Sciences. On March 23, 1840, he informed them that he had created a focussed image of the moon.

The exact date when he first achieved it isn't very clear. While the photograph on loan to the Metropolitan Museum of Art (which cannot be shown here due to rights restrictions) is believed to have been clicked on March 16 based on his laboratory notebook, the one pictured here was by most accounts on the night of March 26, three days after he had announced his success. The fact that many of Draper's original daguerreotypes were lost in an 1865 fire at NYU, and that daguerreotype photographs themselves don't have a long shelf life unless well-preserved from the moment they were taken means that the ones remaining become all the more significant.

The moon pictured here shows an extensively degraded plate with a vertically flipped last quarter moon, meaning the lunar south is near the top. This shows that Draper used a device called the heliostat to keep light from the moon focussed for a 20-minute-long exposure on the plate. They are of the same we and same circular image area as that of his first failed attempts.

Conflict thesis

Apart from being a physician and the first astrophotographer, Draper also has other claims to fame. He was the invited opening speaker in the famous 1860 meeting at Chford University where English naturalist Charles Darwin's ‘Origin of Species’ was the subject of discussion. He is also well known for his book ‘A History of the Conflict between Religion and Science’ which was published in 1874. This book marks the origin of what is known as the "conflict thesis” about the incompatibility of science and religion.

While we will probably never know on which particular March 1840 night Draper captured the first lunar image, his pioneering achievement set the ball rolling for astronomical photography. The fact that he achieved it with a handmade telescope attached to a wooden box with a plate coated with chemicals on the back makes it all the more remarkable.

Picture Credit : Google 

Why does the European Space Agency want to give the Moon its own time?

The European Space Agency announced that space organisations around the world are considering how best to keep time on the moon. The need is for an internationally accepted lunar time zone.

How do you keep track of time on the moon?  What is the lunar reference point? The moon needs to be given its own time zone, the European Space Agency announced recently. As the race to the moon begins and more and more lunar missions are getting deployed, it is become, pertinent to come with a common refer time.

The European Space Agency announced that space organisations and the world are considering how best to keep time on the moon. The idea took out at a meeting in the Netherlands last year in such the participants agreed on the imminent need to set up    “ a common lunar reference time” Pietro Giordana, a navigation system engineer of the space agency said.

“A joint international effort is now being launched towards achieving this, “Giordano said in a statement.

As of now, a moon missions on the time of the country that is operating the spacecraft. The need is for an internationally accepted lunar time zone. This will be easier for all space-faring nations as mare countries and even private companies are aiming for the moon. The NASA is also getting art to send astronauts there.

 The question of time confounded NASA as it was designing and building the international Space Station, fast approaching the 25th anniversary of the launch of its first pierce. The space station doesn’t have its a time zone, But it runs on Coordinated Universal Time, or UTC which is meticulously based on atomic clocks. This ensures in splitting the time difference between NASA and the Canadian Space Agency, and the other partnering space programmes in Russia, Japan and Europe.

Debate is going on among the international team looking into lunar time on whether a single organisation should set and maintain time on the moon.

When it comes to keeping time on the moon, there are technical issues involved. One being that clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, according to the space agency. Also, ticking occur differently on the lunar surface than in bar orbit.

The lunar time will have to be practical for astronauts there, noted the space agency’s Bernhard Hufenbach. NASA is gearing up for its first flight to the moon with astronauts in more than a half-century in 2024, with a lunar landing as early as 2025.

“This will be quite a challenge” with each day lasting as long as 29.5 Earth days, Hufenbach said in a statement. “But having established a working time system for the moon, we can go on to do the same for other planetary destination.” Mars standard Time, anyone?

Picture Credit : Google 

How about learning a bit about the stellar world?

Every star is a giant, bright ball of hot gas. Ever wondered how the stars form and how they die eventually? How about learning a bit about the stellar world?

One septillion stars, that’s almost the number of stars estimated to exist in our universe, Our Milky Way alone contains more than 100 billion stars. The nearest star to us is our Sun. Every star is a giant ball of hot gas. They are the building block of galaxies. "We are made of star stuff,” said noted astronomer Carl Sagan. It means that whatever we are composed of whatever our physical bodies are made of the raw materials that make up our physical bodies were created from the matter from long-extinguished stars. How about learning a bit about the stellar world?

Stars and their birth

Stars are made of huge balls of hot gas it is largely composed of hydrogen and small parts of helium and a few other elements. The star is held together because of its own gravity.

Every star goes through its own unique life cycle. Stars are born within hinge clouds of dust and gas called molecular clouds and are scattered throughout the galaxies. The gas in the molecular clouds clump together, forming high-density pockets, and often collide with each other. With each collision, more matter gets added to it and its mass grows. The gravitational force becomes stronger. The clumps of gas and dust then collapse under their own gravitational attraction. As this happens, the material heats up because of the friction and leads to the formation of a protostar which is also called the baby star. The set of stars newly formed from molecular clouds are called stellar clusters.

Life of a star

The energy of a protostar is derived from the heat released by its initial collapse. As years pass by, the high pressure and temperature inside the core of the star lead to a nuclear fusion reaction, where the nuclei of hydrogen atoms combine together to form helium. The energy that gets released post-nuclear fusion is enough to prevent it from collapsing under gravity.

At any time, there are two opposing forces acting on a star that prevent it from collapsing. There is the gravity of the star which tries to shrink the star, while the energy released following the nuclear fusion in the stars core leads to outward pressure. This outward push will resist gravity's inward squeeze.

When a star is in the phase of undergoing a nuclear fusion reaction, it is called a main sequence star. This is also the longest phase of the star’s life. It has to be noted that as time passes, that is over millions of years, the size, luminosity and temperature of the star also change. The gas in the star is its fuel and its mass determines how long the star will live. This is because a massive star will end up burning a lot of fuel at a higher rate to generate enough energy to prevent it from collapsing: Meanwhile, lower mass stars will burn longer and shine for longer periods, some trillions of years whilst the massive ones may live for just about a few million years.

How does a star die?

When the star runs out of hydrogen to convert into helium, it marks the beginning of the end of the star’s life. Its core collapses leading to the death of the star. A star’s death is largely dependent on its mass. In the case of a lower-mass star, its atmosphere will keep on expanding until it becomes a giant star and the helium gets converted into carbon in its core. Over time the outer layers of the star will get blown off and the cloud of gas and dust expands. This expanding cloud is called a planetary nebula. All that is left now is the core. This is called a white dwarf star which will cool off over the following billions of years.

But what happens in the case of a high-mass star? The fusion leads to the conversion of carbon into heavier elements which then fuel the core. This process produces enough energy to prevent the core from collapsing. This goes on for a few million years until the star runs out of fuel. This is followed by a supernova explosion. The core either becomes a neutron star or a black hole

The supernova explosion is the biggest explosion that occurs in space. It releases material into the cosmos and this matter will then form part of the future molecular clouds and thereby become part of the stars.

Picture Credit : Google 

What is doomsday fiction?

Imagine a world wrecked by a natural disaster, devastated by nuclear war, or destroyed by a pandemic. While this may sound all too familiar because of the prevailing COVID-19 pandemic, apocalypse fiction is a literary genre that has existed for many years. A subset of science fiction, apocalyptic and post-apocalyptic fiction, also known as doomsday fiction, imagines what life will be like at the end of the world.

How it began

An apocalypse is an event that results in mass destruction and change. Although apocalyptic themes exist in many religious texts, the 20th and 21st centuries have given rise to this genre. The aftermath of World War I, World War II, and the nuclear arms race proved to be fertile ground for writers and filmmakers to conjure up a world plagued by zombies, murderous robots, climate change and even a nuclear holocaust

Apocalyptic vs Post- Apocalyptic

Apocalyptic and post apocalyptic literature is set in a time period where the earth as we know it is coming to an end. An apocalyptic novel or film tells the story of the end of the world, unfolding during the timeline of the story. For example, the 2004 film, “The Day After Tomorrow shows what happens when a sudden worldwide storm plunges the entire planet into a new ice age. On the other hand, post-apocalyptic works portray life in the wake of a cataclysmic event. They focus on how the characters deal with the consequences of a disaster. A 2007 film “1 am Legend” starring Will Smith, is a good example. It follows Robert Neville, a scientist who is the last human survivor of a plague in the whole of New York, as he attempts to find a way to reverse the effects of the human-made virus.

Popular examples

Books written under this genre can be broadly classified (based on their themes) into post-disaster wastelands zombie apocalypse, nature gone wrong, machines taking over the world, and dystopian worlds. Here are a few examples.

Post-disaster wastelands

  • “The Stand” by Stephen King
  • “The Mad Max” film series by James McCausland and George Miller

Zombie Apocalypse

  • World War Z by Max Brooks
  • “The Walking Dead”, a graphic novel series by Robert Kirkman, Tony Moore, and Charlie Adlard

Dystopian worlds

  • “The Hunger Games” by Suzanne Collins
  • “Divergent” by Veronica Roth

Machines taking over

  • “The Maze Runner by James Dashner
  • The Big Melt” by Ned Tillman

 

Picture Credit : Google

Suggested Posts