Historical Context
One always wonders how humanity got here and, while humanity has looked up into the stars since the dawn of our time, we are everyday nearing the answers in the search for life in the universe. From studying the origins of life here on Earth to actively looking for signs of life in other galaxies we’ve come a long way… quite literally, light years! The space race might’ve seen a lot of technological advancements that got us to the moon, but since then we’ve sent many instruments to mars and even beyond that to the ends of our solar systems, some of the technology that is up in orbit now or have been used is technology from only 40-50 years ago. From the voyager 1, to The Hubble space craft, or the rovers and orbiters we’ve sent out, humanity has been able to make some impressive achievements since the 60’s.
As technology has improved, the need to create new projects has bolstered and with it presented many new opportunities for the space industry, including the ambitious creation of The Habitable Worlds Observatory. The Habitable Worlds Observatory or HWO is one of the biggest missions of the 21st century recommended by the National Academies Decadal Survey on Astronomy and astrophysics not just because we are hoping to answer the greatest questions to life but also because space scientists and later the government agreed that we needed to create a large telescope that will look for life and the planets that harbor it in the universe. The HWO is it so important for the search for life in the universe because it will look at exoplanets that are like Earth, analyze them for signs of life, and answer many other questions we may have about the universe while we literally observe the universe for signs of other habitual worlds.
Present Day
While the The Hubble Spacecraft has been in orbit since the 90’s it is essentially relying on technology from the 80’s that might not only be older but falling apart. There has been 5 missions to reservice the Hubble Space Telescope and while the aircraft is older than 30 years now its also important that we began to decide wether or not the telescope will come down in the next 10 years or stay up as long as it can. While the future of the Hubble Spacecraft is debated it is the recommendation of the 2020 Decadal Survey that an observatory be built and sent to space with the sole purpose of looking for life with the most state of the art tools available to us now. The Hubble has instruments that allow us to observe the universe, and so does the James Webb Space Telescope, yet the HWO will be especially designed and pointed to specific areas in the universe that will likely have life. Much needed updates and expanded capabilities in the space industry have left us excited to work on getting this launched as soon as possible, possibly being launched by 2030 or 2040 at the earliest is what NASA is shooting for.
What are they looking for? How?
According to Mary Anne Limbach in a journal for The Astronomical Journal titled “Exomoons and Exorings with the Habitable Worlds Observatory. I. On the Detection of Earth–Moon Analog Shadows and Eclipses” she explains how “The Habitable Worlds Observatory (HWO), proposed in the National Academies' "Pathways to Discovery in Astronomy and Astrophysics for the 2020s" decadal report (National Academies of Sciences & Medicine 2021, henceforth "Astro2020"), is a concept for a large space telescope operating in infrared, optical, and ultraviolet wavelengths. The mission's primary objective is to locate and analyze habitable planets outside our solar system, aiming to directly image at least 25 potentially habitable worlds” (Limbach) They will use many methods using these instruments to find habitable exoplanets, in habitable zones, and search for biosignatures in those places that are most likely to contain earth like qualities or harbor any type of life.
We don’t comb the entire universe, there are planets in areas that make them likely targets for the harboring of life that scientists already have their eyes on that might give us strong clues. The Astro2020 report published their survey titled “Pathways to Discovery in Astronomy and Astrophysics for the 2020s ” where they talk about how “Life on Earth has profoundly altered the planet’s atmosphere (Figure 1.1). Interpreting such “biosignatures” is not simple, but the interplay of atmospheric components such as water, oxygen, methane, and carbon dioxide can be modeled to search for evidence of life on other planets. Astronomers have already demonstrated the ability to use spectroscopy to study the atmospheres of large, hot worlds; with future facilities, the same techniques will measure the composition of small, habitable planets.” (National Academies of Sciences, Engineering, and Medicine.) Biosignatures can be some of the the first ways we can distinct life bearing planets from non-life bearing planets as the organisms that live on that planet will create enough chemical signatures that can not be accounted for by any other non-biological means. An example of this would be if there more carbon dioxide in the atmosphere than can be created by geologic means. According to the 2020 Decadal survey they already shown that they have the instruments and the mind power to work on this and scientists are confident in moving forward with this mission.
This is truly a massive project that can be possible using todays technology and in fact is being planned with only technology we have today, with a readiness level of 6 or 7 out of 9, in the hopes it can be ready in time for use on the mission. This readiness creates a large difference between how missions are funded today versus how they were in the 60’s when missions were made in the hopes the technology catching up which could lead to massive delays and the need for more funding. These days we’re hoping to take technology we already have and improve on it the best we can that way there’s less stalling from incomplete technology we may not have and unexpected necessary fund increases that naturally comes from prolonging the missions.
Caleb K. Harada mentions this in their journal for The Astrophysical Journal titled ”Setting the Stage for the Search for Life with the Habitable Worlds Observatory: Properties of 164 Promising Planet-survey Targets” where he says “The Astro2020 report recognized that the unprecedented nature of HWO's science objectives and technology requirements will require sophisticated planning and review leading up to the mission design stage. Astro2020 therefore recommended a Great Observatory Mission and Technology Maturation Program (GOMAP) whose aim is to make early significant investments in the comaturation of mission concepts and technologies prior to ultimate recommendation and implementation (National Academies of Sciences, Engineering, & Medicine 2021). The outcomes of the GOMAP phase will inform the final design of HWO.” (Harada) Creating the technology that will be used for future scientists likely not of this generation as it will only be ready in 20 years is not something we want to leave up to chance, so the investment in current technologies and how they will be implemented becomes absolutely necessary when creating the plans for the vehicle that will be searching for signs of life and answering the questions of universe.
Bigger Picture?
So what exactly are some of the questions they’re asking and how will they be able to find the answers or signs of life? Besides how the universe is expanding and possibly the origins of those grand celestial bodies, some of the main questions scientists are asking are not only how did life come to be but are there places in the universe that were habitable of life and are there currently any signs of life? We’re not looking for signs of intelligent life or little green men when we look for life and we’re not asking if these planets are habitable for humans to live on when we ask these questions. So what are we looking for? Basically we’re looking for any signs of life, or self containing chemical reactions that can reproduce like plants or smaller organisms, which can be done by looking for chemical evidence in the atmosphere. However there is a chance that life on other planets isn’t like Earth life and is surviving through other means for which scientists are ready and counting for. Could life be based on silicone on these aliens planets rather than carbon based life we’ve grown accustomed to? Ideally with more clear data we can begin to ask more questions, as well as find the answers to other questions, and hopefully much of life’s mystery can begin to be solved when the HWO starts to analyze the planets and stars outside of our solar system.
Conclusion
All in all, the Habitable Worlds Observatory is it so important for the search for life in the universe not only because it will look at exoplanets that are like Earth, but because it will analyze them for signs of life, and hopefully answer other questions we may have about the universe. The Habitable Worlds Observatory will look for signs of life on planets that are likely to harbor life upon the recommendation of the 2020 Decadal survey making it one of the biggest and most important missions up to date! The Habitable Worlds Observatory shows us that there is a need for new projects as technology gets better and ambitions rise. There’s so many examples of this as so much that came after the moon landing like Voyager 1, The Hubble Space craft, rovers, orbiters that were huge achievements for humanity as a whole. The space race might have led humanity to the moon, but clearly there has been many technological strides in the space industry since then that have been carried out that have led us to capture data from nearby planets and even beyond that of our own solar system, with some of that still bearing technology from the 70-80’s! We’ve gone literal light years to find the answers in the search for life in the galaxy and beyond, looking for signs of life that may mimic qualities of that of our own planet. As we continue to look into the sky and wonder if there’s life out there or how exactly it is that life came to be it becomes more apparent everyday that with all the technological advancements that we see, we are inching closer to the answers in the search for life in the universe.
Sources
Harada, C. K. (2024, May 23). Setting the Stage for the Search for Life with the Habitable Worlds Observatory: Properties of 164 Promising Planet-survey Targets. The Astrophysical Journal. https://iopscience.iop.org/article/10.3847/1538-4365/ad3e81
Limbach, M. A. (2024, July 5). Exomoons and Exorings with the Habitable Worlds Observatory. I. On the Detection of Earth–Moon Analog Shadows and Eclipses. The astronomical journal. https://iopscience.iop.org/article/10.3847/1538-3881/ad4a75
National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. https://doi.org/10.17226/26141.