Webb telescope is about to see the beginning of our universe

At the end of last year, world science achieved another milestone, that could bring new knowledge about the origin of our lives – on December 25, 2021 a new space telescope was launched into space on the Ariane 5 spacecraft. It bears name of the second director of NASA space agency, James Webb and will replace the existing Hubble Space Telescope. Ing. Ján Baláž, PhD., space designer and member of the Institute of Experimental Physics SAS and International Academy of Astronautics talks more about this groundbreaking event of the space research in the episode “Kontakty” (Contacts) on Radio Slovensko. 

Webb Telescope is the largest and most powerful telescope launched into space. The cost of its production exceeded 10 billion dollars. The launch of the telescope into space was initially planned in 2007, but the device was not fully completed until 2016. Subsequently, it passed a series of demanding tests. James Webb Space Telescope is the result of cooperation of the NASA, the European Space Agency (ESA) and Canadian Space Agency (CSA).

Scientists have high expectations from the new telescope: it was designed to peer back over 13 billion years to the past and it is expected to bring groundbreaking scientific knowledge. To shield the heat radiation from the Earth and the Sun, the telescope includes a shade/sun visor with the dimensions of a tennis court and the shape of a kite. Thanks to this, the telescope can observe distant light in space. The telescope is tuned for radiation in a way so we can observe what was visible millions of years ago. It will also study the near universe – whether, for example, there is a life on any of the many newly discovered planets.

“At first glance, the new telescope is larger, has a larger mirror, and paradoxically weighs only half its weight (5.5 tons) compared to its predecessor, the Hubble Telescope. But while the Hubble Telescope flew around the Earth at an altitude of 550 km, the Webb Telescope will orbit the so-called a liberation point 1.5 million kilometers away from the Earth towards the Sun and thanks to the shielding it will be able to observe the universe without interference,” explains Ján Baláž from the Institute of Experimental Physics SAS. It will operate at very low temperatures, the range of wavelengths on which this telescope is focused is also different (larger wavelengths dominate). Thanks to the large data collection area, it is about hundred times more sensitive than the Hubble Telescope, and has more modern detectors. “Delays in its development have been caused by technical problems, but new ideas and more advanced technologies have emerged as well, and a significant share of delays were due to demanding tests to ensure the telescope’s very high reliability, as we cannot count on service missions common to the Hubble Telescope,” adds Ján Baláž, who is also member of the International Academy of Astronautics.

Technical characteristics of the new telescope:

It weighs 6 tons, the diameter of the mirror is 6.5 m (consists of 18 hexagonal segments), the area of the mirror is 25.5 m², the focal length of the primary mirror is 131 meters, the shield has dimensions of 14 x 21 m, and consists of five layers of mirror metallized Kapton foil, on the sun side has solar panels, four detectors with different filters, coronographs, etc.

Ján Baláž emphasized that during the the preparation and development stage of the Webb telescope, it was extremely important to emphasize high reliability, the use of the components of the highest available quality and, last but not least, testing in conditions that are as similar as possible to the environment in which it will work.

A revolutionary novelty of the new telescope is also a more detailed observation of planets and their satellites outside our Solar system (the so-called exoplanet). Webb telescope will be able to study the density of the planets and the composition of its atmosphere. This will allow scientists to determine if there is life on the studied planets. According to scientists, the telescope will be able to analyze the atmospheres of up to 300 exoplanets (for comparison: the Spitzer and Hubble telescopes were able to analyze the gas atmosphere of only 100 planets). “Finding life on other planets is a problematic thing,” explains J. Baláž. “We are probably not able to say directly that there is life on the planet. We can only follow the so-called biosignatures, i.e. composition of the atmosphere, whether it emerged in purely inorganic way, or if it contains elements which can suggest presence of some form of life.” The search for water, carbon dioxide, methane, oxygen, ozone – these elements suggest there could be life on the planet. “We can never certainly say that there’s any life there or has been until we’ve been contacted by some aliens,” jokes the experimental physicist.

The telescope has many other tasks, thanks to the fact that it sees further than previous telescopes – more than 13 billion light-years, which is very close to the formation of our universe (13.8 billion years). “At that time – after the previous dark age of the universe – the first stars and galaxies formed, and the Webb telescope should already be able to see them more clearly than its predecessors,” says J. Baláž.

Until a few decades ago, almost nothing was known about the stars and their planets. Then, according to J. Baláž, “the exoplanet research expanded rapidly”. There are several methods to detect them. The scientist claim, that their occurrence is much more likely than their absence. The Webb Telescope should contribute to the research of these planets.

James Webb Space Telescope will focus and examine in as much detail as possible, for example, the Trappist-1 planetary system, which has up to seven exoplanets about the size of Earth, and many of them are expected to bear some form of life.

Will the telescope see the Big Bang? “It can get very close, but technically it is not quite possible,” explains J. Baláž. “According to research and theoretical models, our universe is 13.8 billion years old, but for a relatively long time – 380,000 years – it was highly ionized and not transparent to electromagnetic radiation that could not penetrate this barrier. After this period, there was a period of great darkness and only after 100 million years, the first stars ignited and the first galaxies were formed. Scientists expect that the telescope will examine these first stars and galaxies.”

Ján Baláž says, that during these days, the telescope is about 85 percent of the way to the so-called liberation point L2 and is almost unfolded (the thermal shield that isolates it from the Sun and Earth has already been spread) and is partially cooled. According to the scientist, mirrors made of beryllium (a metal that is relatively light but strong) and gilded with a thin layer of gold will be adjusted and calibrated for quite a long time. It will take several months, so we can expect the first images from space about half a year after the launch. According to J. Baláž, it will be things we have not seen and expected so far.

 

Original source: HERE