The James Webb Space Telescope- World’s most powerful telescope

The James Webb space telescope or JWST will replace the Hubble space telescope. It will help us to see the universe as it was shortly after the big bang. It was named after the second head of NAS James Webb. James Webb headed the office of space affairs from 1961 to 1968. This new telescope was first planned for launch into orbit in 2007 but has since been delayed more than once, now it’s been scheduled for 18 December 2012. After 2030 the Hubble will go on a well deserved rest since its launch in 1990 its provided more than a million images of thousands of stars, nebulae, planets and galaxies. The Hubble captured images of stars that are show about 380 million years after the big bang which supposedly happened 13.7 billion years ago. These objects may no longer exist, we still see their light. Now we expect James Webb to show us the universe as it was only 100 to 250 million years after its birth. It can transform our current understanding of the structure of the universe. The Spitzer space telescope and Hubble telescopes have collected data of gas shells of about a hundred planets. According to experts, the James Webb is capable of exploring the atmospheres of more than 300 different exoplanets.

The main mirror- A giant honeycomb consisting of 18 sections.

The working of James Webb space telescope

The James Webb is an orbiting infrared observatory that will investigate the thermal radiation of space objects. When heated to a certain temperature, all solids and liquids emit energy in the infrared spectrum; here there is a relationship between wavelength and temperature. The higher the temperature, there will shorter the wavelength and higher the radiation intensity. James Webb sensitive equipment will be able to study the cold exoplanets with surface temperatures of up to 27° Celsius. An important quality of this new telescope is that it will revolve around the sun and not the earth unlike Hubble which is located at an altitude of about 570 kilometers in low earth orbit. With the James Webb orbiting the sun, it will be impossible for the earth to interfere with it, however he James Webb will move in sync with the earth to maintain strong communication yet the distance from the James Webb to the earth will be between about 374,000 to 1.5 million kilometers in the direction opposite of the sun. So its design must be extremely reliable.

The James Webb telescope weighs 6.2 tones. The main mirror of the telescope is with a diameter of 6.5 meters and a colleting area of 25 square meters, it resembles a giant honeycomb consisting of 18 sections. Due to its impressive size, the main has to be folded for start up; this giant mirror will capture light from the most distant galaxies. The mirror can create a clear picture and eliminate distortion. A special type of beryllium was used in the mirror which retains its shape at low cryogenics temperature. The front of the mirror is covered with a layer of 48.25 grams of gold, 100 nanometers thick; such a coating best reflects infrared radiation. A small secondary mirror opposite the main mirror, it receives light from the main mirror and directs it to instruments at the rear of the telescope. The sunshield is with a length of 20 meters and width of 7 meters. It composed of very thin layers of kapton polyimide film which protects the mirror and tools from sunlight and cools the telescope’s ultra sensitive matrices to 220° Celsius.

The NIRCam- Near Infrared Camera is the main set of eyes of the telescope, with the NIRCam we expect to be able to view the oldest stars in the universe and he planets around them. The nurse back near infrared spectrograph will collect information on both physical and chemical properties of an object. And the MIRI mid-infrared instrument will allow you to see stars being born many unknown objects of the Kepler belt. Then the near infrared imager and sliteless spectrograph or NIRIIS camera is aimed at finding exoplanets and the first light of distant objects. Finally the FGS- Fine Guidance Sensor helps accurately point the telescope for higher quality images updates its position in space sixteen times per second and controls the operation the steering and main mirrors. They are planning to launch the telescope with the help of the European launch vehicle Ariana 5 from the kourou Cosmodrome in French Guiana space center. The device is designed for between 5 to 10 years of operation but, it may serve longer. If everything goes well, $10 billion worth of construction and one year of preparation will have finally started in orbit.

The deepest image of universe ever taken- Hubble Space Telescope

The Hubble space telescope is the most famous telescope in the world. It was named after the famous astronomer Edwin Hubble who changed our understanding of the universe proving the existence of other galaxies. It is an automatic observatory, has discovered millions of new objects in space. It helped us to witness the birth of new stars, found planets outside the solar system and see super massive black holes. Hubble was launched in 1990, and from December 1993 to may 2009, the telescope was repaired and updated four times. Astronauts visited HST five times in order to make repairs and new instruments.

Hubble holds the record for the longest range of observation. The light from the most distant galaxies has taken billions of years to travel across the universe and reach Hubble. By taking this picture, Hubble was literally looking back in time to the very early universe. You can notice on the right side of the image, there is a galaxy very much like the Milky Way that galaxy is about five billion years away, so we are looking back in time by five billion years. In March 4th, 2016, NASA releases a historic image, one that many believed was impossible. It captured the farthest away of all known galaxies; it’s located about 13.4 billion light years away from us. The light from his galaxy has just reached the earth crossing the distance that separates us; hat is now we can observe it as it was 400 million years after the big bang. This galaxy is 25 times smaller than our galaxy, the Milky Way.  It helped to find the age for the universe now known to be 13.8 billion years, roughly three times the age of earth.

This view of nearly 10,000 galaxies is called the Hubble Ultra Deep Field. The snapshot includes galaxies of various ages, sizes, shapes, and colours. The smallest, reddest galaxies, about 100, may be among the most distant known, existing when the universe was just 800 million years old. The nearest galaxies – the larger, brighter, well-defined spirals and ellipticals – thrived about 1 billion years ago, when the cosmos was 13 billion years old. The image required 800 exposures taken over the course of 400 Hubble orbits around Earth. The total amount of exposure time was 11.3 days, taken between Sept. 24, 2003 and Jan. 16, 2004.

With the advanced camera of the NASA’s Hubble space telescope, it discovered a new planet called Fomalhaut b which orbiting is parent star Fomalhaut. Fomalhaut is 2.3 times heavier and 6 times larger than the sun around it is a disc of cosmic dust which creates the resemblance of an ominous eye. Fomalhaut b lies 1.8 billion miles inside the ring’s inner edge and orbits 10.7 billion miles from its star. Astronomers have calculated that Fomalhaut b completes an orbit around its parent star every 872 years. The Fomalhaut system is 25 light years away in the constellation Piscis Australis. But in April 2020, astronomers began doubting its existence; the planet is missing in the new Hubble pictures. Scientists believe that this planet was a cloud of dust and debris formed as a result of a collision of two icy celestial bodies.

Fomalhaut – The the brightest star in the constellation of Piscis Austrinus

In 1994, Hubble captured the most detailed image of the iconic feature called the pillars of creation. The pillars of creation are fascinating but relatively small feature of the entire eagle nebula. The blue color in the image represent oxygen, red is sulfur, and green represents both nitrogen and hydrogen. The nebula was discovered in 1745 by the Swiss astronomer jean Philippe Loys de Cheseaux, is located 7,000 light years from earth in the constellation Serpens. During its work Hubble has presented millions of images but unfortunately NASA has suspended missions to repair and modernize the telescope. It is assumed that in 2021, Hubble will be replaced with the new James Webb space telescope.