The Next Big Thing: The Habitable Worlds Observatory and Inaugural HWO25 Conference
The Habitable Worlds Observatory (HWO) is NASA’s next flagship observatory for the 2030s, following its top rank for large space projects in the Astro2020 decadal survey. With transformative ultraviolet, optical, and infrared capabilities, HWO is envisioned as a true “super Hubble” to not only tackle one of humanity’s oldest questions — Are we alone? — but also to also pursue enduring and emerging questions across all of astrophysics and cosmic origins, from cosmology to the life cycles of galaxies, stars, and planets.
After almost two decades of conceptual development in form of ATLAST, HDST, and the pre-decadal LUVOIR and HabEx studies, the HWO concept is now under active scientific and engineering development at NASA with its industrial, academic, and international collaborators.
In late July, STScI and JHU hosted a conference at the Hopkins Bloomberg Center on Pennsylvania Avenue in Washington, D.C. The meeting was timed for the reveal of two new Exploratory Architecture Concepts (with the largest featuring an outer diameter of 10 meters), the end of the term for the HWO START Community Working Groups, and the launch of the Community Science and Instrument Team and NASA Program Office Science Interest Groups.
The conference brought together scientists, technologists, and policymakers to discuss the state of HWO’s scientific and technological development as it advances toward a new start by 2030 and launches later in the next decade. Recording of all talks are on the STScI Research YouTube channel.
The Amazing Science
Over 500 people attended the HWO25 conference and its evening reception. All told there were 122 talks spread over the plenaries, 6 parallel sessions, 10 panels, and 177 poster presentations. The science talks ranged across the full scope of modern astrophysics and planetary science.
HWO’s design is driven by its goal to detect and characterize dozens of Earth-like planets to assess their habitability and search for signs of biological activity, and also to help us understand how these worlds fit into the architecture of solar systems generally. Numerous speakers highlighted groundbreaking astrophysics measurements, from constraints on the dark matter particle(s) and the gas flows that make galaxies to the creation and transport of the chemical ingredients of life and the most massive black holes — and virtually everything in between. On top of all this, HWO will reveal solar system objects with unprecedented visual detail and contribute to planetary defense of the Earth (and eventually the Moon and Mars) by tracking asteroids and interstellar comets as they cycle through the solar system.
The Advancing Technology
HWO presents unique technical challenges associated with the high contrast needed to detect Earth-like planets orbiting Sun-like stars, and the precise, picometer-scale wavefronts needed to maintain this contrast. These challenges are being met by a robust program of technology development that has already started in earnest, with updates presented at the meeting.
The audience saw the first end-to-end integrated modeling from the HWO engineering team, a number of coronagraph and other instrument tech results, as well as contributions from industry for ultra-stable telescope mirrors, disturbance-free structures, and protective barrel prototypes being subjected to simulated micrometeorite hits.
The technology roadmap for HWO, also extensively discussed at the meeting, is well underway. HWO is being designed to be serviceable and a panel discussed the benefits of building an observatory that can adapt to unforeseen discoveries, incorporate next-generation instruments, and sustain transformative science for decades while also advancing capabilities that connect directly to the emerging space economy and future human exploration beyond Earth.
A Global Community
International partners have made critically important contributions to U.S.-led flagship missions, dating back to ESA’s partnership on Hubble starting in the 1970s. As a joint project of NASA, ESA, and the Canadian Space Agency, JWST has proved yet again that global participation enables more ambitious missions than the U.S. could do on its own.
International interest in HWO is already strong, and there was robust international participation in HWO25, including space astrophysics leadership from the U.K., France, Italy, Canada, the Netherlands, Japan, Brazil, Spain, and Korea. HWO may ultimately prove to be the largest international collaboration to date.
While formal partnerships are years away, international teams are already coming together to build science cases, study instrument designs, and begin collaborating. We can easily imagine the whole globe coming together to find another Earth.
What’s Next
In June, NASA convened a new Community Science and Instrument Team (CSIT) to help guide the next stage of HWO maturation. CSIT will help the Project Office refine the science cases toward Level 1 requirements and assess the science yields of the technical concepts. The CSIT will hold an open community event at the January AAS meeting in Phoenix, Arizona.
To assist CSIT in these efforts, NASA has convened a Science Interest Group (SIG) for HWO, which welcomes broad community participation. A list of science cases being considered by the CSIT are found at the HWO Community Science Case portal.
For more information about HWO, visit:
Astrobiology, Astronomy,
