How About...Herschel

188 years later, Herschel still gazes at the skies.

A new combination of Newton’s and Herschel’s knowledge, helped scientists discover more secrets from our nearest (2.5 million light-years) spiral Galaxy: Andromeda (M31)

 This past December 25^th, Newton and Herschel took a deep and meticulous gaze up into the skies. Yes, you read correctly, ESA’s (European Space Agency) observatories XMM-Newton and Herschel Observatory combined their seeing capabilities, to take a more thorough look to our neighbor Andromeda.

But first of all, we all know Sir Isaac Newton for his apocryphal apple-tree anecdote, but How About…Herschel?

Well Sir William (Wilhelm) Herschel was born in Hannover, Germany in 1738. He began as a musician, his father and brother were musicians too. He first played Oboe, then while in England he became music teacher. After that he was an organist at Halifax.

But his life changed completely at the age of 35. He bought a rather interesting book, a book that would definitely transform his whole course. That book was James Ferguson’s Astronomy.

After that simple action of buying a book changed everything. He began getting interested more and more in astronomy. In just a couple of years he became one of the most powerful telescope-makers.

His life became more and more interesting when strange celestial bodies began appearing at his telescopes. March 13^th 1781, Herschel found something he thought was a comet. But in fact it was the planet Uranus! Right after his discovery he was elected to the Royal Society on December 7, 1781.

After a first finding of the Saturn Nebula, NGC 7009 following September 1782, he started his systematical and extensive survey of the skies visible from his location in England in March, 1783, always assisted by his sister Caroline. After initial trial-and-error attempts, he started with regular, sky "sweeps" on October 23, 1783, with his 47.5 cm aperture, 66 cm focal length reflector, with standard magnification 157 and a field of view of 15'4". He made his next discovery on October 28, 1783: NGC 7184, Herschel's H II.1, a little conspicuous galaxy in Aquarius of 11.2. Only 18 months later, he had cataloged 1,000 new objects completed a second 1,000 in 1789 and a final additional 500 objects in 1802, so he ended up in discovering about 2500 new "nebulae" and star clusters in about 20 years.

He also discovered two moons of Uranus, Oberon and Titania.

Now that you know a bit of Herschel’s life, let’s proceed.

The Herschel and XMM-Newton observatories were able to capture something new at Andromeda. Herschel telescope is capable of analyzing infrared wavelengths, while X,MM-Newton is able to capture X-Rays.

But how are those wavelengths going to help discover something new?

Well, infrared light is commonly emitted by new-forming stars. While on the other hand X-Rays are released by those old stars that are slowly dying.

So Herschel and Newton combined their seeing skills and they achieved what no one did before:

Capture the most detailed image of Andromeda Galaxy, ever.

This high resolution image shows the new coming stars.

Image taken by ESA Herschel Observatory

This new forming stars could take hundreds of millions of years, because it is a slow process in which thanks to gravitational force, the stars begin to pull together their own materials. Once they have reached the adequate high density, the stars will begin emitting visible light to the human eye.

Apart from that, scientists are amazed by the enormous 75,000 light-years, ring surrounding the galaxy. They believe it might have been the result of a recent collision with another galaxy. With this new study, they have also been able to capture 5 more rings inside the galaxy.

While this other image (X-Rays) shows the dying stars.

Image taken by XMM-Newton Observatory

They are commonly found at the centre of galaxies. They are the result of star-fights. Sometimes two stars get locked together and they begin a fight until one of them is defeated. Once this happens, the dying star will begin pulling gas out of the still living star. When this gas travels through space, it is heated and therefore releasing X-Rays.  Then little by little, the dying star is heading towards its own doom. When this gases are highly condensed by the gravitational force of that zombie-star, it will collapse therefore: explode.

And finally here is a combination of both images. Which are not visible from Earth because most part of the radiation is absorbed by Earth’s atmosphere.

X-Rays and Infrared Wavelengths, combined

I hope you enjoyed, stay in touch for more.

I.