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Mystic Mountain in the Carina Nebula: pillars of dust and gas
Photo: Hubble / NASA
Edwin Hubble almost slipped away from science.
Then the space telescope named after him, one of the most powerful instruments in astronomy, would probably have a different name today.
But the American found his way back to research after completing a law degree at Oxford and working as a lawyer for a short time.
At the beginning of the twenties of the last century, Hubble suddenly enlarged the then known universe.
He showed that the Andromeda Nebula is more than a simple gas cloud in which young stars are born.
Instead, it's a whole galaxy - so our Milky Way is just one of many.
The Hubble space telescope does the same as its namesake.
Thanks to the flying observatory, we have insights into distant areas of space that we could hardly have looked into in such detail before.
For 30 years, the 13-meter-long barrel has been floating through space, around 550 kilometers above the earth.
If things go as planned, Hubble will be replaced by the James Webb space telescope at the end of the year.
The advantage of Hubble is its location in space.
Because when observing from Earth there is a problem for astronomers.
The atmosphere disrupts the signals that telescopes are supposed to pick up.
It is also impermeable to some of the radiation in the electromagnetic spectrum - to X-rays or light in the ultraviolet range, for example.
This also includes radiation in the infrared spectrum.
The problem does not exist in space.
This is one of the reasons why Hubble takes great pictures.
The human eye can only see a small part of the radiation - visible light.
But the electromagnetic spectrum goes further.
Radio waves or X-rays are also included.
The Hubble telescope works mainly in the visible light range, but it also receives infrared signals or ultraviolet radiation.
It is above all the wonderful images of cosmic gas and dust clouds that made Hubble famous.
The Pillars of Creation, the pillars of creation, are now among the most famous images from space.
The image taken by the telescope is a section of the Eagle Nebula, it is around 7,000 light years away and 20 light years in size.
It consists mainly of hydrogen and is associated with a star cluster.
The two images above show the different spectral ranges in which the image was taken.
With infrared light layers of dust and gas are penetrated, the astronomers can look much deeper into the cloud.
This makes it possible to see young stars that could not be seen in the optical range.
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The Hubble Telescope and its Spectrum
Hubble has also repeatedly photographed planetary nebulae.
From the perspective of earth telescopes, they didn't look particularly interesting.
But only the high resolution of the Hubble Space Telescope revealed their complex shapes.
Planetary nebulae have nothing to do with planets.
Because they mostly look like a gas planet from a distance, they were originally given this name.
The French Charles Messier observed these structures in the 18th century.
Around 1500 such planetary nebulae are known in our Milky Way alone.
The closest to earth is the Helix Nebula in the constellation Aquarius, 700 light years away.
They arise when a star is at the end of its life due to strong stellar winds
Pushes gases and plasma into space.
The energy of the dying star inside makes the gas and dust around them glow - the result is the wonderful images from space that Hubble takes for us.
However, the coloring only arises on earth.
Hubble itself can only take black and white images.
Only afterwards are the different wavelengths from the observations assigned to a color.
So to a certain extent the pictures are art.
It was not initially foreseeable that Hubble would become a success story after all.
When the space shuttle “Discovery” dropped the space telescope in space on April 24, 1990, it was immediately disappointed.
Because of a planning error, the telescope only provided images that were hardly better than those from earth telescopes.
Only after a type of corrective lens had been installed on a repair mission for the 2.4-meter mirror did Hubble deliver the hoped-for images to the control center in the US state of Maryland.
Gradually, most of the technology was modernized.
But now Hubble is getting on in years.
How long it will continue to serve is uncertain.
The last service mission took place in 2009.
And now, after some delays, the successor will finally fly into space this year, the "James Webb" telescope.
If everything goes as planned, the billion-dollar telescope will fly into space with an "Ariane 5" rocket at the end of October.
According to the plan, the 6.5 meter main mirror of the infrared telescope will then unfold around 1.5 million kilometers from Earth.
For astronomy, it is perhaps the hoped-for next step in exploring space.
Or as Edwin Hubble once put it: "The history of astronomy is a story of receding horizons."
Icon: The mirror