Indian Scientists with the Help of James Webb Telescope Formulate Model To Trace Elusive Exo-Moons

This may also help detect habitable exo-moons in the future and understand new worlds beyond our own.

NASA’s James Webb Space Telescope (JWST), which is touted as the most powerful telescope ever built, was successfully placed in outer space last year in December. And, with the help of this JWST, scientists at the Indian Institute of Astrophysics (IIA), Bangalore, have developed a model to trace the so far elusive exomoons – natural satellites that revolve around exoplanets (planets orbiting stars other than the Sun).

So far, five thousand exoplanets --- planets orbiting stars other than the Sun, have been discovered by using several ground-based and space telescopes such as Kepler, CoRoT, Spitzer, and Hubble space telescopes. However, the natural satellites or exomoon around any of these planets still remain untraced.

Scientists at the IIA, Bangalore, which is an autonomous institute of the Department of Science and Technology (DST), have demonstrated that the newly launched James Webb Space Telescope (JWST) is sufficiently powerful to detect the transit signal of exomoons in the photometric light curves of moon hosting exoplanets.

Schematic diagram of moon hosting exoplanet and its model photometric transit light curve

Professor Sujan Sengupta and his graduate student Suman Saha have developed an analytical model that uses the radius and orbital properties of the host planet and its moon as parameters to model the photometric transit light curve of moon-hosting exoplanets by incorporating various possible orientations of the moon-planet-star system. 

The co-alignment or non-coalignment of the orbits of the planet and the moon are used as parameters (using two angular parameters), and they can be used to model all the possible orbital alignments for a star-planet-moon system. Using these generic models and the analysis of photometric transit light curves of exoplanets that is being obtained by JWST, a large number of exomoons can be detected in near future. 

According to the researchers, an exo-moon around a gas giant planet like Jupiter in the habitable zone of the host star where temperature is appropriate for water to exist in liquid state may harbour life. Under favourable alignment of moon-planet-star, such exomoon may also be detected by JWST. The research has been accepted for publication in The Astrophysical Journal, which is published by the American Astronomical Society (AAS).

The Most Powerful Telescope Ever Built and Worth $10 Bn To Launch in October

Image ~  James Webb Space Telescope

NASA’s James Webb Space Telescope (Webb), which is touted as the most powerful telescope ever built, remains on schedule for a launch readiness date no earlier than Oct. 31, 2021. However, Webb has no launch date constraints; hence, it can launch almost any day of this year, said NASA in a release.

A premier observatory of the next decade, the James Webb Space Telescope is fully booked by scientist around the world to peer at other planets and the origins of the universe. These include about 400 studies that are scheduled and could reveal secrets about the oldest galaxies, inhabitable planets and even the dawn of the universe, scientists said.

The Webb telescope, named for NASA’s second administrator, James E. Webb, is years behind schedule and billions of dollars over budget, with the cost approaching $10 billion.

Webb is an international collaboration among NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). It as a 5-layer sunshield that protects the telescope from the infrared radiation of the Sun, Earth, and Moon; like having sun protection of SPF 1 million.

Webb will orbit the Sun 1.5 million kilometers from the Earth. (Hubble orbits 560 kilometers above the Earth)

Webb’s Golden Mirror Wings Open One Last Time on Earth
[Image ~  James Webb Space Telescope]

Webb will be the largest telescope ever placed in space; 100 times more powerful than Hubble. So big it has to fold origami-style to fit in the rocket and will unfold like a "Transformer" in space. It will peer back in time over 13.5 billion years to see the first galaxies born after the Big Bang.

Once launched, Webb will be the largest, most powerful and complex space telescope ever built and launched into space. It will fundamentally alter humans' understanding of the universe. The powerful telescope will orbit the sun, a million miles away from Earth at the second Lagrange point. (L2 is four times further away than the moon!)

NASA aims to finally launch it Oct. 31 aboard a European Ariane 5 rocket made by France-based Arianespace from Europe’s Guiana Space Center in French Guiana, a region of France in South America. This is the European Space Agency’s contribution to the international project, which also involved the Canadian Space Agency.

The Webb observatory will be much larger the Hubble Space Telescope, which was launched in 1990. Webb’s main mirror, or light-gathering surface, is 21 feet across, compared to Hubble’s at 7.8 feet. Webb’s solar shield, which will keep its infrared instruments cold in space, is about the size of a tennis court. The telescope will orbit the sun, almost one million miles from Earth.

The longer wavelengths enable Webb to look much closer to the beginning of time and to hunt for the unobserved formation of the first galaxies, as well as to look inside dust clouds where stars and planetary systems are forming today.

Astronomer and physics professor at Arizona State University, Rogier Windhorst, said --

It’s going to be like Galileo first looking at the sky through a telescope. Our eyes are going to be reopened to the universe. …So, we’re going to see new and unexpected things that we’ve never dreamed of before.

Webb will ship to the launch site in August with little to no schedule margin; launch processing will take two months. The observatory has completed all the post-environmental testing deployments, and it is in its final integration and folding stages. Final stow, closeout, and pack and ship are imminent. 

NASA is working closely with the European Space Agency (ESA) and Arianespace on establishing the launch date. 

Webb will study every phase in the history of our universe, including the first luminous glows after the creation of the cosmos, the formation of solar systems capable of supporting life on planets like Earth, and the evolution of our own solar system.