Exploring the Universe: NASA’s Exoplanet Discoveries

Why in news?

• NASA’s journey to explore space and whether or not there is other life in the universe has had a recent boost with the discovery of six more exoplanets, totaling the amount up to 5, 502.
• This achievement is not just a figure on a list; it means the increase and the various technologies in the study of exoplanets.
• This search which started with the identification of the first exoplanets around the pulsar PSR B1257+12 in 1992 has rapidly intensified, more than 5000 exoplanets had been identified by March, 2022.
• It is necessary to get more familiar with those discoveries made recently, how they are identified, and what tools are used to describe the distant planets.

New Exoplanets Overview

• Even in the relatively new classification of six newly confirmed planets, the nature of exoplanets depicts its diversification and characteristic presentations. Here is a closer look at each of these fascinating new additions
  • HD 36384 b: This exoplanet is categorized as a super Jupiter meaning it is larger than Jupiter in the solar system. It revolves around an M giant star; that is much larger than our Sun; thus, it is an example of the diverse types of systems in the universe.
  • TOI-198b: This planet is exciting because it may be a rocky planet and is in the outer rim of the habitable zone of its star. Clarke’s Third thing this zone is the area surrounding the star within which conditions may be suitable fort he status of liquid water and hence the existence of life.
  • TOI-2095b and TOI-2095c: Currently these are the hot super-Earths; they are tinier than Neptune bigger than Earth, and they orbit nearby their star hence, very hot. Both of them are orbiting the same M dwarf star and give recipe information on how the planetary system with several close-in planets develops.
  • TOI-4860b: This is a type of planet referred to as the ‘hot jupiter’- this type of planet is similar to Jupiter in size, but orbits much closer to its parent star meaning that its orbital period is only 1. 52 days. Hot Jupiters force scientists to rethink formation and migration of planets which exist in the meaning of the word.
  • MWC 758c: Really interesting, this giant protoplanet is located in a young star and it has protoplanetary ring around it. This system provides a look at the early stages of accretion, which makes it an attractive focus of research.

Detection Techniques

• Several techniques have been developed to find these distant worlds:
  • Radial Velocity: It focuses on the movement of stars caused by the gravity of other celestial bodies, mainly planets. This for example happens as a planet revolves round a star it makes the star to revolve in a small circle likewise. This motion can be observed with changes in what is called the ‘spectral lines’ emanating from the star.
  • Transit Method: This is the most efficient technique, which helped to find the largest number of now known exoplanets. It looks at how much a star is observed to fade when a planet moves in front of it and only partly occults the star. It could also give an idea of the size of the planet and its orbit around its star, if the distance is measured from the planet to its star.
  • Direct Imaging: It involves taking images of the Exoplanet directly by shielding the source of light which is the star. However, due to the luminosity of stars compared to planets, it has successfully discovered such planets as MWC 758c.

The Role of TESS and Other Telescopes

• Anticipated to image virtually the whole sky, TESS has discovered many thousands of candidates for exoplanets by measuring the dimming of stars.
• It is argued due to the insights provided by TESS, it is highly invaluable in exoplanetary science.
• Other telescopes have also played crucial roles:
  • Spitzer Space Telescope: Prior to its retirement, Spitzer offerred infrared information that was useful in determining the composotion of the observed exoplanets.
  • Hubble Space Telescope: Hubble has greatly contributed in the determination of the atmospheres of exoplanets and the acquisition of direct photographs of exoplanets.
  • James Webb Space Telescope (JWST): Webb is designed to launch in 2021, and it will be millions of times more powerful, permitting more detailed examination of the atmospheres of exoplanets within search for that they might have been able to sustain life.
• Going to the future, Nancy Grace Roman Space Telescope is to be launched by NASA in May 2027. With direct imaging using a coronagraphic device this telescope will prove to be one of the best tools to discover and explore exoplanets. Thus, it may open the prospects of attempting such challenging missions as the organization of Habitable Worlds Observatory designed to search for existence of life not on the Earth.

The universe of exoplanets expanding

• The establishment of over 5000 exoplanets means that the human knowledge of the galaxy and beyond has increased exponentially.
• Here are some key milestones and facts about these fascinating worlds
  • First Proven Exoplanet: The first exoplanet orbiting a solar-type star was 51 Pegasi b, that was detected in 1995 and now known as the first exoplanet of the modern age.
  • Kepler Space Telescope: Starting from 2009 Kepler is one of the most successful missions in the search for the exoplanets, detected thousands of the candidates using the transit method.
  • Diverse Types of Exoplanets: There is a wide range of exoplanets depending on the type of material that made it up, including gaseous super-Earths, and gaseous planets similar to hot Jupiters. Both of them alters the formation and evolution of planets as a concept.
  • Circumbinary Planets: There are some planets that orbit two stars at once instead of one star; such planets are called circumbinary planets. These systems help to detect and explain the behaviour of binary star systems and formation of planets.
  • Habitability and Life: These searches for exoplanets are strongly interrelated with the efforts to find life other than that in Earth. Especially, planets within the zone called the ‘The Goldilocks Zone’ where the conditions might be suitable for the existence of liquid water are of interest for this search. One popular research focus group is the TRAPPIST-1 system that comprises seven Earth-like planets.

Conclusion

• New missions and discoveries of exoplanets by NASA is enlightening the general public. Every new discovery reveals more information about life’s existence and about other planetary systems regarding to more basic questions.
• With the enhanced technologies and new telescopes such as Nancy Grace Roman Space Telescope being set in future, one can only anticipate other truths to surface that will shed much light into the universe and the position of human beings in the universe.
• The search started with the discovery of the first planets outside our solar system has progressed vigorously and with every new discovery, pointed us in a direction that brings us closer to the answer to the questions, ‘What else is out there?’ It seems the future of exoplanetary research is very promising and the prospects are as endless as the universe.

FAQS

Q1: What is an exoplanet?
Ans: It is a planet that orbits a star outside our solar system. These planets can vary widely in size, composition, and distance from their parent stars.

Q2: How many exoplanets have been discovered?
Ans: As of now, NASA has confirmed the discovery of 5,502 exoplanets.