James Webb Space Observatory- A New Horizon in Human History

Key takeaways

***The US space agency says the post-launch set-up of the new James Webb telescope has gone very well.
If a worldwide dust storm engulfs the Red Planet during a moment when Webb can see it, the powerful space telescope will be able to acquire data on the storm, supplementing data from spacecraft on or near the planet’s surface.
Additionally, Webb will examine the moons of gas giant planets, comets, asteroids, and the planets Mars, Jupiter, Saturn, Uranus, and Neptune.

The US space agency says the post-launch set-up of the new James Webb telescope has gone very well. “As smoothly as we could have hoped for.”- BBC News

We shall soon enter a new era of astronomy if everything goes according to plan. The James Webb Space Observatory (JWST), the world’s most extensive, most costly, most complicated space telescope, has launched into orbit and is on its way to its final destination.

The James Webb Space Telescope, also referred to as Webb or JWST, is a massive space-based observatory tuned for infrared wavelengths to complement and expand the Hubble Space Telescope’s findings. It will cover a broader range of wavelengths and have much better sensitivity. Webb can now scan further back in time to locate the earliest galaxies that formed in the early Universe, as well as gaze within dust clouds where stars and planetary systems are developing today.

For the hundreds of scientists, engineers, managers, and support workers who worked to bring the $10 billion James Webb Space Telescope to this point, the launch on Christmas Day 2021 was both exhilarating and scary. After all, JWST’s scientific potential is vast, and it can solve some of the universe’s most pressing problems.

The Mysterious Early Universe #

Although the enigmatic JWST is sometimes labeled a replacement for the Hubble Space Telescope, I like to think of it as a successor. Hubble has been operational for more than 30 years, providing us with incredible vistas of the cosmos and tens of thousands of scientific discoveries. We hope and anticipate that it will continue to run for a significant number of further years.

However, in comparison to ground-based telescopes, the comparatively tiny 2.4-meter diameter mirror restricts the telescope’s sensitivity and capacity to see the faintest objects. Additionally, while Hubble can view in infrared light, it cannot reach the wavelengths of light emitted by the very first stars and galaxies. JWST, on the other hand, will be capable of doing so. It may even observe previously unseen Population III stars (stars produced from primordial material from the Big Bang).

Understanding when the earliest stars originated, just after the Big Bang, and how they became the building blocks of the first galaxies is a critical scientific subject and one of JWST’s key science priorities. We know that the elements necessary for life and modern technology, including carbon, silicon, and gold, were eventually formed in early stars - but we do not have a solid grasp of how this occurred. The need to identify faint objects in the distant cosmos had a significant role in the observatory’s construction, influencing its size, wavelength coverage, and the requirement to keep it extremely cold to avoid unwanted background light.

JWST will carry out a variety of scientific missions and study the first stars and galaxies. It is envisioned as a mufti-purpose observatory where astronomers worldwide may apply for time to do research. For instance, by viewing in the infrared, JWST will be able to peer through the clouds of dust that envelop incredibly young stars, which are opaque to visible light. Unlike Hubble, it will be able to see directly into stellar nurseries, the birthplaces of stars, and their planetary systems. The findings will shed light on how dust and gas clouds collapse to generate stars and how planets develop around them.

Habitability of Exoplanets #

When the earliest JWST ideas were considered more than two decades ago, no planets other than those in our solar system were known. Since then, countless more planets circling other stars in our galaxy have been found by scientists (exoplanets). A sizable portion of the JWST observational mission will be devoted to studying their atmospheres. JWST’s wavelength coverage is optimized for investigating chemicals in extraterrestrial atmospheres and space’s low infrared background, providing a significant advantage over Earth-based observatories.

There are two approaches available. One exploits the fact that planets can pass before their parent star (a phenomenon known as transit), causing a dip in the light emanating from it. We can investigate the planet’s atmosphere with high accuracy by examining the light, split down by wavelength, before and during transit. Another approach uses specialized equipment known as a coronagraph to filter off the light from the parent star, allowing direct imaging of the planet and research of its atmosphere or surface. This might assist in determining whether a planet is habitable, so justifying additional exploration and the eventual deployment of tiny space missions.

The ultimate objective is to discover a planet similar to Earth, but this will take a very suitable combination of conditions, as such planets are anticipated to be uncommon in the solar neighborhood and highly dim compared to the parent star. JWST is most likely to examine gas giants like Jupiter and Saturn and ice giants such as Uranus and Neptune in our solar system. None of the known planetary systems like ours, with several massive planets in tighter orbits than ours, their atmospheres being more intensely heated, and their weather systems being more active and volatile.

JWST will be able to examine our planetary system in addition to investigating planets outside our solar system. Due to its high sensitivity will identify and characterize comets and other ice bodies in the solar system’s farthest regions. These things, which have remained virtually intact since their formation in such a remote region, may provide clues about the Earth’s beginnings, notably the source of its water, which may have been a result of bombardment by such bodies early in its lifespan. JWST will also examine the atmospheres and seasonal weather fluctuations of all planets outside Earth’s orbit around the sun.

Detailed planning and concepts for discovery are critical to justifying the cost of developing an ambitious, game-changing observatory like JWST. However, there will be discoveries that no one can predict. When Hubble was started, the concept of exoplanets was primarily speculative, but it became one of the missions primary objectives. It has become a curious topic: what surprise science JWST may reveal.

How JWST Will Explore Mars #

A dust storm enveloped the whole planet Mars in the summer of 2018. The Sun would have appeared as a small sphere against a dark brown sky from the surface. Dust covered the solar panels of NASA’s intrepid Opportunity rover, preventing it from recharging. From their different vantage points, orbiting spacecraft and the Curiosity rover observed the storm, but none of these robotic explorers had a vista large enough to see the whole planet at once.

When NASA’s James Webb Space Telescope, scheduled to launch in 2021, reaches its million-mile destination a million miles from Earth, it will be able to see the whole disc of Mars every two years. If a worldwide dust storm engulfs the Red Planet during a moment when Webb can see it, the powerful space telescope will be able to acquire data on the storm, supplementing data from spacecraft on or near the planet’s surface.

Reporting Martian weather is only one of the ways that Webb, which was meant to peer into deep space and unravel cosmic riddles, can work with other NASA missions to investigate Mars. Webb can see Mars in the infrared, a wavelength of light undetectable to human sight and is perfect for analyzing certain compounds found in planetary atmospheres. While Web’s primary mission will be to search for chemical fingerprints on faraway worlds circling other stars, called exoplanets, it will also exploit these capabilities on neighboring Mars.

Nonetheless, viewing Mars with Webb will be challenging. “Webb is meant to identify very dim and distant things, but Mars is bright and near,” Geronimo Villanueva, Mars scientist at NASA’s Goddard Space Flight Center, said. Mars will seem very bright to Webb, and engineers must prepare carefully for any planet studies to avoid overexposure of its equipment to light.

Webb’s first chance to gaze at Mars will be in August 2022. When the James Webb Space Telescope was launched in 2021, it will be the world’s preeminent space research observatory. Webb will unravel secrets inside our solar system, explore distant planets orbiting other stars, and delve into our universe’s fascinating architecture and beginnings and our role within it. Webb is a collaborative multinational effort headed by NASA in collaboration with the European Space Agency and the Canadian Space Agency.

JWST- Closer Look #

Launch Vehicle #

Arcane 5 rockets were used to launch the James Webb Space Telescope. The European Space Agency provides the launch vehicle and launch site as part of the mission’s participation. The Arcane 5 is one of the most dependable launch vehicles globally and was chosen for its reliability (it was the only launch vehicle that matched NASA’s standards for launching a mission like Webb) and the value it adds through our international collaboration.

Location of the launch #

Webb was launched from Europe’s Spaceport at Kourou, French Guiana, using Arianespace’s ELA-3 launch facility. It is advantageous to choose launch locations near the equator because the Earth’s rotation might provide more thrust. At the equator, the Earth’s surface moves at a rate of 1670 kilometers per hour.

Vital Information #

The Launch Segment is composed of three basic components:

The launch vehicle will be an Arcane 5 equipped with a cryogenic upper stage. Provided in a single launch configuration, with a large payload fairing measuring up to 4.57 meters in static diameter and 16.19 meters in usable length.
Payload adapter consists of the Cone 3936 plus the ACU 2624 lower cylinder and clamp-band and serves as the mechanical and electrical contact between the Webb Observatory and the Launch Vehicle.
Prepare for and launch the campaign. NASA, ESA, Northrop Grumman, and Arianespace are jointly responsible for preparing and executing the launch campaign.

How Large Will Webb Be? #

The primary mirror diameter is the most critical dimension of a telescope, roughly 6.5 meters (21.3 feet) for Webb. This is about 2.75 times the diameter of Hubble and around six times the area. The Webb will weigh around 6,500 kg, or 14,300 pounds on Earth (everything is weightless in orbit), or little more than half the mass of Hubble. Web’s most significant structure will be its sunshade, which must be capable of shielding both the deployed primary mirror and the secondary mirror tower. The sunshade measures around the same size as a tennis court.

Why Arcane 5 To Launch Webb, Why Not SpaceX? #

We picked Arcane in the early 2000s for its reliability (it was the only launch vehicle that matched NASA’s standards for launching a mission like Webb) and the added value provided by our multinational collaboration.

By “value,” we mean that the European Space Agency provides us with a launch vehicle and associated services without requiring us to make a financial contribution. In exchange, NASA commits to providing European scientists with a share of Web’s observing time (roughly 15 percent). Because Web’s architectural constraints and international technology constraints (along with industrial capabilities and strategic technology interests) precluded us from requesting a spacecraft bus, sun-shield, or telescope components from Europe, we instead requested the launch vehicle, launch services, and science instruments.

Another reason to avoid switching launch vehicles in the middle of a project is that each vehicle has unique environmental characteristics. While all rockets are similar in specific ways, they differ significantly in their primary vibroacoustic modes. They design anything that meets all environmental criteria, increases cost and mass, and limits capabilities.

Conclusion #

The Webb will be able to identify planetary systems in the infrared light of neighboring stars (heat). It will be able to see the reflected light of massive planets the size of Jupiter circling nearby stars directly. Additionally, it will see extremely young planets forming when they are still quite hot. Webb will have coronagraphic capabilities, which will allow it to filter off the light from the planet’s parent star. This is necessary because the parent star will be thousands of times brighter than the planets that circle it. Web’s resolution will be insufficient to detect details on the planets; it will be able to detect only a faint light speckle next to the bright parent star.

Webb will also research planets that transit their parent star. When a planet passes between a star and Webb, the overall brightness of the system decreases significantly. The amount by which the light decreases indicate the planet’s size. Webb can also detect sunlight passing through a planet’s atmosphere, measure its component gases, and determine if the planet’s surface has liquid water. When the planet passes behind the star, the overall brightness decreases, allowing us to determine more parameters about the planet.

Webb can see everything in our Solar System that is further away from the Sun than the Earth. Web’s sensitivity will be particularly advantageous for investigating fragile rocky and ice objects in the far outer Solar System, such as the dwarf planet Pluto and other Kuiper Belt Objects. Web’s observations of these objects will be used to evaluate ideas about the Solar System’s formation. Additionally, Webb will examine the moons of gas giant planets, comets, asteroids, and the planets Mars, Jupiter, Saturn, Uranus, and Neptune.

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