Hubble circles the Earth fifteen times a day at a speed of eight km per second ⎯ at that speed, we'd cross the US in ten minutes.
With him we have seen things that we would not believe before: nascent galaxies beyond the Milky Way, gamma ray bursts, an errant comet colliding with Jupiter, dying stars, bodies sucked into a black hole, fire storms, the interstellar chaos behind the battle, the future and the past in flames... And all these moments will not be lost, like tears in the rain... because Hubble has fixed them on our retina. The space telescope has completed three decades of service and continues to reveal wonders.
"It is also known as 'the people's telescope', as it is not only within the reach of a few professional astronomers: Hubble has brought the Universe into homes around the world." Eva Villaver tells us in an interview by email. "If you have an Internet connection, you have access to the cosmos."
The astrophysicist spent eight years working at the Space Telescope Science Institute (STScI) in Baltimore, the operational center of this instrument. She "she was one of the first people to find out if something sudden happened in the sky." Cosmic spectacles as fascinating as that of newborn stars in the constellation of Orion. “It is where the closest star-forming region is located, just 1,500 light-years from our planet.”
Another of the images that dazzled the Spanish researcher was the detonation of a kilonova in the galaxy NGC 4993. "These explosions are the main factory of heavy elements in the periodic table," she explains. "Specific, the kilonova identified in the photo occurred 2.6 billion light years ago, and in it hundreds of times the mass of our planet were formed in gold and platinum”.
This kilonova occurred 2.6 billion light years ago.
Hubble took its first snapshot in 1990, when they launched it 574 kilometers above our heads. But those frames were blurry at first; in fact, the device was out of action for three years, being the object of ridicule down here. "The error is human, the heroic thing was to correct it."
The optical defect was due to an infinitesimal failure of precision in polishing the telescope's mirrors. "We are talking about a difference of 1/50 times the thickness of a human hair." Fortunately, the artifact was designed so that astronauts could repair it in orbit ⎯programmed durescence⎯; They put contact lenses and the problem was solved.
“Since then, maintenance and improvement work has been carried out on four other missions. Thus it is still a powerful observatory today, thirty years later”. He has doubled his life expectancy and far exceeded any expectation.
"Gazing at the stars before Hubble was like being very nearsighted and trying to see without glasses." You couldn't tell three aliens on a donkey. “The atmosphere absorbs all the energy that reaches us from the sky in certain ranges, causing us to be literally blind from Earth. to certain phenomena and temperatures. Only with Hubble and telescopes outside the atmosphere do we have the ability to see what's out there."
Capture astronomical objects without distortions and in high resolution, at an angular size of 0.05 arcseconds, the equivalent of looking from Madrid at a pair of fireflies in Tokyo as if they were three meters from us.
Eva Villaver in Mauna Kea (Hawaii): “Although when I can really enjoy the beauty of a dark sky it is when I go on vacation in Palencia in the summer”.
"Hubble was intended to explore the distant Universe." Galaxies formed far away and back in time, just four hundred million years after the Big Bang. "In 1998, Hubble discovered that the Universe is accelerating" . Who says Hubble, says Adam Riess, Brian Schmidt and Saul Perlmutter, who thanks to the telescope proved the theory and shared the Nobel Prize in Physics.
“Another of Hubble's contributions is found in the study of exoplanets: he has shown us that they form around many more stars than previously believed, increasing the possibility that life exists somewhere.” He found water vapor in K2-18b, a potentially habitable super-Earth in the constellation Leo, 110 light-years away—a few meter stops away. It is eight times the mass of the Earth and it is the only known exoplanet with temperatures that could support life.”
Super-Earth K2-18b, captured by Hubble.
One of the latest news that the telescope gave was that of the galactic homicide committed by 3XMM J215022.4−055108: it captured this intermediate-mass black hole perpetrating the murder of a star; the victim was absorbed and the crime betrayed the existence of these elusive cosmocides.
Also has predicted the collision of Andromeda with the Milky Way; It will be four billion years from now, but it seems that our neighborhood – the solar system – will not be affected. "Your findings of his have been revolutionary in all fields of astronomy."
To the present, Hubble has taken more than 1.4 million photos, leading to the disclosure of some 17,000 scientific documents. “It is one of the most prolific space observatories in history. It has a very high demand for use”. Each course he gets more than a thousand requests for his goal to point towards new mysteries to solve; but only one in six requests are accepted.
“Only the most creative, impressive and significant ideas will be implemented and will receive the valuable time of the telescope”, points out Villaver. “The member countries of the European Space Agency (ESA) –including Spain– have guaranteed access to 15% of Hubble's observation time. Y European astronomers are the first authors of 40% of publications based on telescope data. There are many projects led by Spaniards among them”.
A 'colored' planetary nebula.
Hubble has also helped Eva Villaver in her research, focused on the hottest stars in the Magellanic Clouds. "These stars live in other galaxies, and they are so far away that without Hubble we cannot distinguish them from the gas that surrounds them," she adds. "They are important because they produce most of the carbon in the Universe, and we are based on this element." They come out very graceful in the Hubble photos.
“My favorite images are all of the planetary nebulae, those vast regions of gas and dust very faint that are often shown in press releases with many colors”.
It is worth saying that there is a lot of impressionist filter involved: the original snapshots are in black and white. Each tone contains information, and is assigned based on wavelength: blue is oxygen; orange, sulfur; green, nitrogen… It is not the real landscape that the human eye would appreciate from a spaceship, but… beauty is true and true, beauty!
“My first contact with a telescope was with the one on Teide. It is a small telescope, fifty centimeters; we pointed to some planet in the solar system, I don't remember if Jupiter or Saturn, and I was quite disappointed, because I had seen Hubble images before. What did fascinate me is contemplating the Canarian sky with the naked eye; a dark sky, protected from light pollution, which should be everyone's heritage and to which, however, we barely have access due to the excess of urban light”.
The constellation of Orion is where the closest star-forming region to Earth is found.
The confinement for Covid-19 reduced light emissions. “You could see further during the day and a few more stars at night; but in a few days we have returned to harmful environmental pollution levels”.
For this reason, observatories are usually installed on top of mountains. Edwin Hubble himself (1889-1953) surveyed the immensity from Mount Wilson. "In 1929 he made a startling finding: all galaxies seemed to be receding at speeds that increased in proportion to their distance from us." The Universe is expanding! "This discovery was a great advance for astronomy at the time."
In his honor, they named the contraption after him; though Hubble's mother – of the Hubble telescope, not the astronomer – was Nancy Grace Roman. "I ran into her several times," says Villaver. "She was one of the first Executive Astronomers Of NASA, and she tirelessly advocated for new tools that would allow scientists to study the Universe from space. The United States pioneered astrophysics thanks to his leadership and vision. He left a tremendous legacy in the scientific community when he died in 2018."
As recognition, the future Wide Field Infrared Survey Telescope (WFIRST) will be called Roman –“It is currently under development”– and will be the successor to Hubble together with the James Webb Space Telescope (JWST), which is scheduled to launch in 2021. “With a sensitivity a hundred times greater and working in the infrared region, Webb will revolutionize fundamental astrophysics. He will look at the Universe in its infancy, observing the first galaxies”.
But Hubble will still have another anniversary to celebrate. “The perspective is that it will be a scientifically productive observatory well into 2025.” Between now and then, His photographs will continue to amaze humanity. The things we would not believe are and will always be infinite.
**· To see the Universe through the eyes of Hubble, we recommend the book Expanding Universe. The Hubble Space Telescope. (Taschen, 2020). **
First Hubble photo: 'Wishing Well Cluster'.