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Retired Space Observatory’s Watery Legacy

Illustration of Herschel Space Observatory in front of an infrared image of the Rosette nebula.   Credit: ESA - C. Carreau
Illustration of Herschel Space Observatory in front of its own infrared image of the star forming region known as the Rosette nebula. Credit: ESA – C. Carreau

 

After nearly four years of glorious service to science, the European Space Agency’s Herschel Space Observatory mission has come to the end this week. Running out of helium coolant needed to chill its instruments down to near absolute zero means that it has closed its far-infrared eyes to the Universe for good.  After a few final tests, controllers will park the retired probe in a permanent solar orbit.

Its mission was a far-reaching one – to study for the first time some of the coldest regions of space and examine the molecular chemistry of objects across the Universe- from distant galaxies and newborn stars to the atmosphere’s of gas giant planets and comets. (Related: Starburst Galaxy could Illuminate Early Universe)

But one of the stand-out legacies of Herschel, according to Michel Fich,  one of the of mission scientists, will be how the space telescope has provided a much greater understanding of the abundance of water outside of Earth and the solar system.

Herschel has helped provide answers in regards to how water may actually get onto planets, even habitable ones, like our own, says Fich.

“We believe that life requires water and all life as we know it is closely tied to its presence,” said Fich, astronomer at University of Waterloo, Ontario, Canada.

“So a question about life in the rest of the Universe has to start with questions like: Is there lots of water in the rest of the Universe? Is water found in high abundance in other solar systems?”

Here are Fich’s four picks for Herschel’s big watery discoveries.

 

1.  Cosmic reservoirs of water that pepper star birth regions

Herschel’s infrared view of part of the water-rich  Taurus Molecular Cloud 450 light years from Earth.  Credit: ESA/Herschel/SPIRE
Herschel’s infrared view of part of the water-rich Taurus Molecular Cloud 450 light years from Earth. Credit: ESA/Herschel/SPIRE

 

Peering at a cosmic cloud of gas and dust  that is on the verge of collapsing and forming sun-like star and planets around it, Herschel discovered enough water vapor inside this nebula to fill Earth’s oceans more than 2000 times over.

This observation in the constellation Taurus is the first detection of water vapor in a cold molecular cloud,  and shows that there is a lot of water in the original clouds that will eventually form a star, and a solar system around it.

 

2.  Creating a solar system with a huge amount of water

 Herschel detected copious amounts of cold water vapor, illustrated in blue in the above illustration, emanating from the star's planet-forming disc of dust and gas. Credit: ESA/NASA/JPL-Caltech
Herschel detected copious amounts of cold water vapor, illustrated in blue in the above illustration, emanating from the star’s planet-forming disc of dust and gas. Credit: ESA/NASA/JPL-Caltech

 

This artist’s impression illustrates an icy protoplanetary disk around the young star TW Hydrae, located about 175 light-years away, where Herschel found a disk around the newborn star that is saturated with water.

This find for the first time shows that water can migrate from the original stellar cloud to the surrounding disk that may one day fragment into planets.

 

3.  Evolution of a comet system around a very young solar system

This Herschel image shows the infrared emission from the young star Fomalhaut and the dust disc surrounding it.that is believed to be formed through comet collisions.  Credit: ESA/Herschel/PACS/Bram Acke, KU Leuven, Belgium
This Herschel image shows the infrared emission from the young star Fomalhaut and the dust disc surrounding it.that is believed to be formed through comet collisions. Credit: ESA/Herschel/PACS/Bram Acke, KU Leuven, Belgium

 

Herschel has studied the dusty belt around 25 light year distant star Fomalhaut and determined that it formed from the ongoing collision of thousands of icy comets..

The big questions facing astronomers now is if this cometary debris will go into making planets, is expelled from the solar system, or form comet belts?

 

4.  Supporting evidence for theory that the Earth’s oceans come from comets

This illustration shows the orbit of comet Hartley 2 in the Solar System. and Herschel's image and the water data.  Credit: ESA/AOES Medialab; Herschel/HssO Consortium
This illustration shows the orbit of comet Hartley 2 in the Solar System. and Herschel’s image and the water data. Credit: ESA/AOES Medialab; Herschel/HssO Consortium

 

Herschel studied comet Hartley 2 using the most sensitive instrument to date for detecting water in space, and has shown that this cosmic iceberg is packed with water that has the identical molecular fingerprint as those found in Earth’s oceans.

The discovery revives the idea that our planet’s seas may have come from comets – presumably falling onto the Earth’s surface after the planet had already formed.  (See: What Created Earth’s Oceans: Comet Offers New Clue)

Comments

  1. Adaora
    Nigeria
    May 12, 2013, 2:59 pm

    The more you delve into the mysteries of the universe and untangle them,the more tangled they seem….one is always left in awe….

  2. CharlesTheMonkey
    Zoo
    May 7, 2013, 4:54 am

    Rain Clouds in space? Sounds cool! But the loss of a hi-tech piece of equipment for discovering WATER seems sad.

    Space exploration is inevitable. What we need are lots and lots of cheap probes sent into space to gather as much data in very little time.

    Need hence is not to go/ see far into space but develop mass expendable cheap space exploration solutions.

  3. Michael Jan R. Alima
    Phillipines
    May 6, 2013, 10:04 pm

    its so amazing!

  4. Angel Ramos
    Puerto Rico
    May 6, 2013, 3:00 pm

    Is just amazing, the wonders of the universe; more and more you want to explore more and more and get lost in the discoveries of how everything works.

  5. saket jain
    dehradun
    May 6, 2013, 1:14 am

    very very nice photos

  6. Rahul
    Vietnam
    May 6, 2013, 12:20 am

    Awsome! So probably, life is not a coincidence of events. But someone (the Creator?) is systematically creating environments conducive to life step by step. First forming stars, then forming planets, then throwing water on the planets, and then bringing microbes there, and then allowing them to evolve in creatures of all sorts over millions of years. And maybe then destroys that planet, and goes on to make another one? Man this is awe-inspiring. Wish I could fly all over the universe to see the birth of a solar system, and birth and evolution of life there!