Astrobiology Missions - Ongoing

The advancement in technology has been a blessing to mankind in many ways, and it is evident in the present space programmes that are being carried out. You would have heard a lot about the Hubble Telescope, James Webb Telescope, etc. These are some of the most  sophisticated space missions that are working in the present day.

Let us look at some of the most interesting ongoing space programmes - functional details, research goals and their relevance in the field of astrobiology.

1. Voyager 1 & Voyager 2: These two spacecrafts that are still operational and have the capacity to operate for a few more years, were launched in 1977. Voyager 1 was launched on September 5th, and Voyager 2, three weeks before that, on August 20^th. It was named so for the order in which it arrived in the orbit of its target planet, Jupiter. Voyager 1 took a faster trajectory, while Voyager 2 took a slower trajectory that allowed a close flyby of Uranus and Neptune too (Voyager 2 Launched Before Voyager 1 | NASA, n.d.).                                                                                                                   It provides a much closer view of the giant planets in the solar system: Jupiter, Saturn, Uranus, and Neptune. They are well known for their findings about the solar system, like the, active volcanoes of Jupiter’s moon, Io, Jupiter’s rings, newly found moons around Uranus and Neptune, and the presence of liquid nitrogen in Neptune’s moon, Triton. Voyager showed the presence of a thick atmosphere on Saturn’s moon, Titan, and it encouraged the development of Cassini-Huygens spacecraft (Voyager | Missions | Astrobiology, n.d.). It has travelled beyond Neptune and Uranus, where no other spacecraft has gone before, where solar wind mixes with the interstellar wind of our galaxy, and it is still sending data as clearer view of the distant parts of our solar system is relevant to understanding more about the possibility for life to survive on the planets and moons (Voyager 1 & 2 – NASA RPS: Radioisotope Power Systems, n.d.).

2. Hubble Space Telescope: On April 23rd, 1990, the highly praised and laudable NASA Hubble Space Telescope was launched. It gave interesting revelations about the age of the universe and the presence of dark energy. It is a Cassegrain reflector telescope working in the ultraviolet, visible, and near-infrared range of the spectrum. This is the first telescope that had to be repaired, either for replacement of its parts or for updating the instrument, by a group of astronauts back from earth. The 2011 Nobel prize was awarded to scientists who discovered that our universe was rapidly accelerating by a force called dark energy and the pictures captured by Hubble were used for this finding (In Depth | Hubble Space Telescope – NASA Solar System Exploration, n.d.).

The fact that Hubble works like a time machine is interesting as it gives the data of the object as it was when the light left it (it takes a long time for light to travel and reach us), rather than providing the present day information. This was possible due to the 2009 and 2022 upgrades made to the telescope by adding the Wide Field Camera 3 and the cosmic origins spectrograph (Hubble, the "Incredible Time Machine" | NASA, n.d.). Researchers were also able to determine the age of the universe by measuring the Cepheid variable stars, and it was found to be nearly 13.7 billion years old (Hubble Space Telescope: Pictures, Facts & History | Space, n.d.).

Hubble studied the various stages of a star’s life, from being an infant to their death, even the stars from other galaxies like the Andromeda Galaxy. It also studies planets orbiting other stars, and it could get clearer images of Jupiter, Saturn, Ceres, and Pluto. It also found new moons of Pluto (Hubble Space Telescope: Pictures, Facts & History | Space, n.d.) (Hubble Space Telecope | Missions | Astrobiology, n.d.). As a result, the Hubble telescope is extremely helpful in attempting to answer fundamental questions about the universe, its origin, life on other celestial bodies, and so on. It helps in understanding the formation of a planet or star from dust and helps in finding exoplanets that have the chances of being habitable.

3. Gemini Observatory: It is a ground-based telescope consisting of two telescopes, each of 8.19m in length, which were installed on February 1^st, 1999. This observatory gave an almost complete view of the sky by situating it at two different locations. Gemini North is located in Hawaii and Gemini South is located in Chile, providing proper atmospheric conditions for viewing the sky (dry and less cloudy). This is a National Science Foundation (NSF) programme in association with a group of other research universities. It is an optical/infrared telescope involved in finding planets outside our solar system, helping to understand their potential to host life.

This observatory gives the International Gemini community preferential access to the entire sky with the vision of spreading knowledge about the Universe and the beautiful mysteries stored inside it. Direct imaging and data analysis of the planets outside our solar system that emit only one millionth of the light of our host star are made possible using the Gemini Planet Imager. It is used to study the lives of stars at a distance, the structure of galaxies, massive black holes, and quasars (Gemini Observatory | Missions | Astrobiology, n.d.).

4. Chandra X-ray Observatory: Originally known as the Advanced X-ray Astrophysics Facility (AXAF), it was renamed in honour of the great physicist Subrahmanyan Chandrasekhar (Chandra X-Ray Observatory, n.d.). It was launched in July 1999, and the Smithsonian’s Astrophysical Observatory in Columbia is behind the operation, analysis of data, and distribution of data to the research community around the world (Chandra | Missions | Astrobiology, n.d.). It is another of NASA’s powerful time machines, as it can give a picture of some quasars as they were 10 billion years ago (NASA - Chandra X-Ray Observatory Quick Facts, n.d.).

It is NASA’s specially designed telescope to study the faint signals emitted by the hot objects in the Universe as it gives high-resolution images of the exploded stars, giant galaxies, and black holes. As the x-rays get absorbed by the gases in the earth’s atmosphere, the Chandra Observatory should fly high above, at almost 139,000 km altitude (Chandra | Missions | Astrobiology, n.d.). This is approximately 200 miles away from the location of the Hubble telescope and almost a third of the distance to the moon (Chandra :: About Chandra :: The Facts Behind the Top 10 Facts, n.d.).

The study of the high energy regions of the universe has provided astrobiologists with data about the origin and evolution of the universe, its stars, the conditions in which the planets are formed, and the distribution of radiation and its roles in modifying the habitability of the planet. The data from Chandra is used to learn about the universe, the conditions favourable for the formation of a planetary system, and which ones could be habitable (Chandra | Missions | Astrobiology, n.d.).

5. Mars Science Laboratory: NASA’s Mars Science Laboratory mission was launched on November 25th, 2011 and the Curiosity rover it contained landed in Gale Crater on Mars (MSL | Missions | Astrobiology, n.d.). The Curiosity rover, which is the largest and most advanced rover sent to Mars until then, has been exploring the Martian land since August 2012 (MSL | Missions | Astrobiology, n.d.). The primary goal of the Curiosity rover is to find evidence of the existence of microbial life in the past and the potential for life to survive there. It is also made to analyse the chemical composition, structure, and the process of formation of Martian rocks and soil (In Depth | Curiosity (MSL) – NASA Solar System Exploration, n.d.). It is the size of a car, carrying 17 cameras, and the robotic arm is equipped with laboratory instruments in order to carry out sample analysis (Mars Science Laboratory Curiosity Rover-Mars Missions-NASA Jet Propulsion Laboratory, n.d.).

The Curiosity rover is studying the weather conditions and the geology to understand more about habitability on the Red Planet. A few weeks after the landing of the rover, it found evidence of a past river-bed where water could have been flowing billions of years ago, which suggests that Mars could have been habitable years ago. The rover even drilled a few inches into Martian rock and collected samples whose analysis showed the presence of sulphur, nitrogen, oxygen, carbon, and phosphorous and traces of clay materials too. All this evidence suggests that the Martian ground where the rover landed would have been habitable years before (Mars Rover Curiosity’s 7 Biggest Discoveries (So Far) | Space, n.d.) (MSL | Missions | Astrobiology, n.d.).

6. Mars Atmosphere and Volatile Evolution (MAVEN): This American Orbiter was launched on May 11th, 2013. This spacecraft is used to study the atmosphere of the red planet, Mars. It is also used to understand the interaction of the sun and solar wind with the planet’s atmosphere. This mission is giving insight into the reasons behind the loss of the planet’s earlier atmosphere. The loss of atmosphere is thought to be one of the reasons for the planet's transformation from a life-supporting planet with liquid water to the present-day dry Martian land. Astrobiologists are using MAVEN results to understand when the loss of water from Mars’s surface happened and when the habitable environment was lost from its surface (MAVEN | Missions | Astrobiology, n.d.).

7. Atacama Large Millimeter/Submillimeter Array (ALMA): This interferometer, located on Chile's Chajnantor Plateau, is a collaborative international astronomy program. Light signals from space will be absorbed by the water molecules in the earth’s atmosphere. In order to get a clearer view of the distant galaxies and the birth of new stars and planets, the telescope is situated in one of the driest places on Earth (ALMA - Atacama Large Millimeter/Submillimeter Array | ESO, n.d.). The partners in this project include the European Southern Observatory (ESO), the National Science Foundation (NSF) of the United States, and the National Institutes of Natural Sciences (NINS) of Japan. The largest ground-based telescope in the world was installed on March 13th, 2013 (ALMA | Missions | Astrobiology, n.d.).

ALMA is used to observe light from the cold parts of the universe that fall in the millimetre and submillimeter ranges that are usually dark under visible light, i.e., the infrared and radio waves in the spectrum. It is used to study planets outside our solar system and also provides valuable information about the planets in our solar system and its moons, like Saturn’s moon Titan. Astrobiologists use this data to learn more about the universe, to know the kinds of locations of habitable planets, the dense molecular clouds that form stars, the building blocks of life, etc. ALMA is used to understand the growing universe by studying the dust and gas clouds around a young star and the formation of planetary systems later, thus gathering information about the birth and the gradual growth of planets as well (ALMA | Missions | Astrobiology, n.d.) (ALMA - Atacama Large Millimeter/Submillimeter Array | ESO, n.d.).

8. Transiting Exoplanet Survey Satellite (TESS): Launched on April 18th, 2018, this is an all-sky survey telescope for transiting exoplanets.Transit is a method used to discover exoplanets and it occurs when a planet crosses between a star and its observer and dims its brightness, which is shown in its light curve. The size of the exoplanet can be found from the amount of the lowered star’s brightness (What’s a Transit? – Exoplanet Exploration: Planets Beyond Our Solar System, n.d.). Thus, TESS is used to find planets that can be either Earth-sized or even bigger than that. The main purpose of TESS is to characterise and understand the atmospheres of small planets revolving around bright stars, which can be used in determining the potential habitable planets outside the solar system (TESS | Missions | Astrobiology, n.d.). ESS has been found to survey nearly 75% of the sky, which is a much larger area than the Kepler telescope.TESS is known to find 66 planets outside our solar system and over 2000 candidates are yet to be confirmed (Transiting Exoplanets Survey Satellite (Transiting Exoplanets Survey Satellite (TESS) – Exoplanet Exploration: Planets Beyond Our Solar System, n.d.).

9. James Webb Telescope: NASA’s biggest and most powerful orbiter telescope was launched on Christmas Day in 2021, helping to give a view of the universe 200 billion years after its origin. It is an infrared telescope that can see through the dust clouds to study the young stars and planets that are being formed. Learning the kind of atmosphere the exoplanets are have, helps gain more knowledge about the habitable zone in a solar system (What Is the James Webb Space Telescope? | NASA Space Place – NASA Science for Kids, n.d.). Thus, astrobiologists are also looking forward to the telescope’s valuable findings. It is very tall, covering the area of a tennis court, and it is folded inside the rocket for launching.

It uses gold-coated mirrors to focus light from distant stars (What Is the James Webb Space Telescope? | NASA Space Place – NASA Science for Kids, n.d.). There is a 21-foot primary mirror and 18 small hexagonal mirrors joined in the form of a puzzle (In Depth | James Webb Space Telescope – NASA Solar System Exploration, n.d.). It is coated with gold to ensure maximum reflection of infrared light on its instruments, allowing them to learn about its origin and the environment through which it travelled. Gold reflects 99% of light falling on it rather than silver or aluminium which will reflect only about 85% and they are reactive with the outer atmosphere (Why NASA Chose Gold for the James Webb Space Telescope’s Mirrors?, n.d.).

As we have seen, the ability of Viking 1 is not same as the ability of Hubble or Voyager. Our knowledge of the universe has also increased as the years went by and new, greater, more advanced, space missions happened. We are all waiting to know what the James Webb Telescope is going to tell us about the history of our universe and the possibility of having any life form in or outside our solar system. Let us hope to have even better and more sophisticated space programmes to happen and that you can all be a part of it.

References:

1. ALMA - Atacama Large Millimeter/submillimeter Array | ESO. (n.d.). Retrieved February 28, 2022, from https://www.eso.org/public/teles-instr/alma/
2. ALMA | Missions | Astrobiology. (n.d.). Retrieved February 28, 2022, from https://astrobiology.nasa.gov/missions/alma/
3. Chandra :: About Chandra :: The Facts Behind the Top 10 Facts. (n.d.). Retrieved February 27, 2022, from https://chandra.harvard.edu/about/top_ten.html
4. Chandra | Missions | Astrobiology. (n.d.). Retrieved February 27, 2022, from https://astrobiology.nasa.gov/missions/chandra/
5. Chandra X-ray Observatory. (n.d.). Retrieved February 27, 2022, from https://heasarc.gsfc.nasa.gov/docs/chandra/chandra.html
6. Gemini Observatory | Missions | Astrobiology. (n.d.). Retrieved March 1, 2022, from https://astrobiology.nasa.gov/missions/gemini-north-and-gemini-south/
7. In Depth | Curiosity (MSL) – NASA Solar System Exploration. (n.d.). Retrieved February 28, 2022, from https://solarsystem.nasa.gov/missions/curiosity-msl/in-depth/
8. In Depth | James Webb Space Telescope – NASA Solar System Exploration. (n.d.). Retrieved March 1, 2022, from https://solarsystem.nasa.gov/missions/james-webb-space-telescope/in-depth/
9. Mars Rover Curiosity’s 7 Biggest Discoveries (So Far) | Space. (n.d.). Retrieved February 28, 2022, from https://www.space.com/20396-mars-rover-curiosity-big-discoveries.html
10. Mars Science Laboratory Curiosity Rover - Mars Missions - NASA Jet Propulsion Laboratory. (n.d.). Retrieved February 28, 2022, from https://www.jpl.nasa.gov/missions/mars-science-laboratory-curiosity-rover-msl
11. MAVEN | Missions | Astrobiology. (n.d.). Retrieved February 28, 2022, from https://astrobiology.nasa.gov/missions/maven/
12. MSL | Missions | Astrobiology. (n.d.). Retrieved February 28, 2022, from https://astrobiology.nasa.gov/missions/msl/
13. NASA - Chandra X-ray Observatory Quick Facts. (n.d.). Retrieved February 27, 2022, from https://www.nasa.gov/centers/marshall/news/background/facts/cxoquick.html
14. TESS | Missions | Astrobiology. (n.d.). Retrieved February 28, 2022, from https://astrobiology.nasa.gov/missions/tess/
15. Transiting Exoplanets Survey Satellite (TESS) – Exoplanet Exploration: Planets Beyond our Solar System. (n.d.). Retrieved February 28, 2022, from https://exoplanets.nasa.gov/tess/
16. What’s a transit? – Exoplanet Exploration: Planets Beyond our Solar System. (n.d.). Retrieved February 28, 2022, from https://exoplanets.nasa.gov/faq/31/whats-a-transit/
17. What Is the James Webb Space Telescope? | NASA Space Place – NASA Science for Kids. (n.d.). Retrieved March 1, 2022, from https://spaceplace.nasa.gov/james-webb-space-telescope/en/
18. Why NASA chose gold for the James Webb Space Telescope’s mirrors?(n.d.). Retrieved March 1, 2022, from https://www.republicworld.com/technology-news/science/why-nasa-chose-gold-for-the-james-webb-space-telescopes-mirrors.html

Image Credits:

• http://astronomy.com/bonus/hubble
• https://spaceplace.nasa.gov/voyager-to-planets/en/neptune.en.jpg
• https://esahubble.org/images/heic2017a/
• https://spaceplace.nasa.gov/mars-curiosity/en/curiosity-selfie.en.jpg
• https://spaceplace.nasa.gov/james-webb-space-telescope/en/infrared-camera_smoke.en.jpg
• https://spaceplace.nasa.gov/james-webb-space-telescope/en/JWST_mirrors.en.jpg

Roslin Elsa Varughese