My Science School

Vega became the first star other than our sun to be photographed. Visible in the summer sky of the northern hemisphere, Vega is a bright star located about 25 light years from our Earth. On July 16-17, 1850, The days when we could look up to see star-studded skies feel like they are numbered. Especially in cities, as the light pollution makes it impossible for us to enjoy the celestial show. Some stars, however, shine bright enough such that they can be seen even on a moonlit night or from light-polluted cities.

Vega is one such star visible in the summer sky of the northern hemisphere. The brightest star in the constellation Lyra, it is also known as Alpha Lyrae. The fifth-brightest star visible from Earth, it is also among the closest of all bright stars at about 25 light years away.

The Summer Triangle

Along with two other stars - the distant Deneb and the fast-spinning Altair-the blue-white Vega forms an asterism known as the Summer Triangle. These three stars are usually the first to light up the eastern half of the sky after sunset.

Beginning around June and until the end of the year the Summer Triangle pattern can be discerned in the evening every day. Vega, which sinks below the horizon for just seven hours each day, can actually be seen on any day of the year. At mid-northern latitudes on midsummer nights, Vega is usually directly overhead.

The blue-white light of Vega is so bright that it has been observed through the centuries. Be it the Hindus, Chinese, or the Polynesians, the star features prominently in many ancient cultures. Its name, meanwhile, comes from the Arabic word wagi, which means "falling" or "swooping"

First to be photographed

The brightness has meant that Vega has remained relevant in modern times as well, notching up a number of firsts. The first of those firsts came in 1850, when Vega became the first star to be photographed, other than our sun.

On July 16-17, 1850, a 15-inch (38 cm) refractor at the Harvard College Observatory was employed to capture it. Harvard's first astronomer, William Cranch Bond, had been dabbling with celestial photography at the behest of John Adams Whipple, an American inventor and photographer. Using the daguerreotype process, the duo achieved a 90-second exposure of Vega that yielded the first photograph of a star other than our own. Bond and Whipple, in fact, kept at it and their daguerreotype of the moon the next year created quite a stir at the international exhibition held in London's Crystal Palace.

Spectrum of a star

A couple of decades later, Vega was again central to another first. Henry Draper, an American doctor and amateur astronomer, was a pioneer in astrophotography. He chose Vega as his subject when he created the first spectrographic image of the star in 1872. Breaking down Vega's light to reveal the various elements making up the star, Draper had taken the first spectrum of a star other than our sun.

Late in the 1990s, Vega rose to prominence once again after American astronomer Carl Sagan's novel "Contact" was made into a Hollywood movie. As the movie showed an astronomer discovering a signal appearing to come from Vega while searching for extraterrestrial intelligence, the star captured popular imagination.

Vega's blue-white light indicates surface temperatures of about 9,400 degree Celsius, much hotter than that of our sun (4,000 degree Celsius). Vega's diameter is nearly 2.5 times that of the sun, while its mass is also more than twice that of our sun.

Vega is only about 450 million years old, making it a youngster when compared to our sun, which is 4.6 billion years old. Despite Vega being a 10th of the sun's age, both stars are classified as middle-aged as they are halfway through their respective lives. This means that while our sun will run out of fuel only after another 5 billion years, Vega will burn for only another half-a-billion years.

Picture Credit : Google 

Whether it is the possibility of making contact with alien life, or the mere thrill of the unknown, UFOs have always intrigued us.

It's a bird. It's a plane. It's a UFO! Unidentified Flying Objects or UFOS are exactly the stuff that legends are made of, and have since time immemorial held people in its thrall. From conspiracy theories of their sightings, portrayal in books and movies, their link to alien invasions, and more, have ensured that the topic has remained relevant even with the change of governments and lapse of time.  Naturally, a day dedicated to these mysterious flying saucers was just waiting to happen. Earlier, June 24 was allotted as the day of celebration, for, according to aviator Kenneth Arnold, it was on that day that nine unidentified objects had flown over Washington in the 1990s. However, July 2 was officially allotted as World UFO Day to commemorate the supposed UFO crash incident that occurred in Roswell, New Mexico, in 1947.

The Rosewell Incident It famously refers to the 1947 recovery of balloon debris from a ranch near Corona, New Mexico, by U.S.Army Air Forces officers from the Roswell Army Air Field, and conspiracy theories which emerged decades later, claiming that the debris involved a flying saucer and that the truth had been hushed up by the US government.

Throughout 1947, people across the U.S.. and other countries had been reporting sightings of strange objects in the sky and claiming that. they were alien-piloted spacecrafts In the midst of this the flying saucer furore, in July that year, some unusual material fell on the ground near Roswell. Soon after, an information officer at the Roswell Army Air Field (RAAF) issued an unauthorised press release stating that a flying disk" had been retrieved from a local ranch. The Roswell Daily Record immediately printed the story headlined "RAAF Captures Flying Saucer On Ranch in Roswell Region"

The officer was admonished and the Army duly retracted the statement and said that the crashed object was a conventional weather balloon. While the incident slowly died down, it eventually laid the ground for several hoaxes in the future.

Picture Credit : Google