Our understanding of the cosmos is set to shift thanks to many new space telescopes.
Magic Mountain a 3-light year tall pillar of gas. Images like these were never possible before the Hubble Space Telescope began surveying deep Universal time.
In the coming decades, NASA will embark on its most ambitious effort to expand its space telescope inventory. Buoyed by both the scientific and popular success of the Hubble Space Telescope, NASA is developing several space observatories that will explore the most tantalizing questions that physicists and cosmologists want answered.
Over the next 25 years, NASA’s various space telescope missions will look to find earth-like exoplanets orbiting distant stars, determine whether there are biosignatures for life on those planets, map the interstellar medium, and understand dark energy. As if those goals weren’t ambitious enough, NASA will also use its developing fleet of telescopes to determine how galaxies form, and whether the origins of life lay beyond our atmosphere.
To achieve these goals, NASA will engineer, build and launch numerous space telescopes, and we’re here to profile some of the most interesting instruments in the bunch.
The James Webb Space Telescope
NASA’s successor to the Hubble Space Telescope is the James Webb Space Telescope (JWST). Although the JWST has experienced a slew of delays ever since it was first proposed in 1996, once launched it will represent a major leap forward for deep space observation.
The main reason for scientific excitement about the JWST is its absolutely enormous mirror. Measuring in at 6.5 meters in diameter, the
The enormous mirrors of the James Webb Space Telescope will unlock even deeper reaches of out Universe’s history.
telescope’s optics represent a 5.6-fold increase in area over Hubble, meaning researchers will be able to peer further back in time with greater precision.
Beyond its large mirror, the JWST will also sport a Near Infrared Camera (NIRCam), a Near Infrared Spectrograph (NIRSpec), a Mid-Infrared Instrument (MIRI), and the Fine Guidance Sensor and Near Infrared Imager and Slitless Spectrograph (FGS/NIRISS).
Each of these instruments will be used to precisely parse spectral wavelengths beyond human perception to further the latitude of exoplanet and universal investigations. In fact, engineers believe that the James Webb’s infrared capabilities will be powerful enough to see the formation of the Universe’s first galaxies just a few hundred million years after the Big Bang.
The James Webb is currently scheduled for launch in March 2021.
The WFIRST Telescope
Following on the heels of the JWST, NASA will launch the 2.4-meter Wide Field Infrared Survey Telescope (WFIRST) telescope.
While small in size, the WFIRST could help solve one of the biggest problems in cosmology, namely, where did dark energy come from.
The WFIRST will complement the JWST by offering further infrared observations using its 288-megapixel multi-band near-infrared camera that will beam back exceedingly sharp images. Additionally, the WFIRST’s coronagraph instrument will give the telescope a high contrast, small field of view imager that will combine both visible and near-infrared observations.
While smaller in size, the WFIRST has still been assigned a number of important scientific missions. Chief among them will be answering basic questions about cosmic acceleration. Cosmologists will be looking to WFIRST to help them answer if dark energy is causing cosmic acceleration, whether dark energy is constant across the universe, and whether dark energy has evolved over the course of the Universe’s history.
In addition to those enormous questions, the WFIRST will also help complete a census of exoplanets, help determine if they’re within habitable parameters, and take direct images of the spectra of many worlds orbiting other stars.
The Origins Space Telescope
The Origins Space Telescope (OST) is the first of four telescopes (three of which we’ll cover here) that NASA is considering as its future Large Strategic Science Missions (LSSM), a class of near-future projects that are among NASA’s most costly, and scientifically potent missions.
As currently envisioned, the OST will image the exoplanets in the mid- to far-infrared range using a filled aperture telescope with a diameter of either 9.1 or 5.9 meters. Whether NASA decides to go with either the smaller or larger diameter versions of the OST imager, the missions will explore exoplanets in the 6-40 μm range of the spectrum in search of bodies that exhibit atmospheric characteristics capable of supporting life.
In addition to its main infrared instrument, the OST will also be equipped with spectrographs that will allow researchers to build 3D surveys of the Universe that can be used to uncover and classify distant objects like galaxies, solar systems and exoplanets.
To keep the telescope’s instruments from frying under the heat of the Sun, the OST will carry cryocooling equipment that will maintain optimal thermal conditions for the instrument’s detectors (∼50 mK) and optics (~4 K).
The Large UV Optical Infrared Surveyor
The second project that NASA is considering in the LSSM field is the Large UV Optical Infrared Surveyor (LUVOIR), a multi-wavelength general-purpose observatory.
Although it is only in the conceptual phase, mission planners envision the LUVOIR having the capacity to explore deep into the history of the Universe, possibly as far back as the reionization epoch (~400 million years ago). During the beginning of this era the Universe was still a loose affiliation of gases yet to see the first galaxies or quasars form. Over the course of a roughly 600-million-year reionization period, galaxies would evolve and our Universe would begin to resemble a very nascent form of its present self.
The LUVOIR is expected to pick this information out of the noise of cosmic entropy and time.
On top of that feat, the LUVOIR system will also be asked to capture information about other periods in the Universe’s evolution and perform sophisticated spectroscopy on exoplanet bodies. These observations would be aimed at precisely characterizing whether an exoplanet emitted a biosignature of life.
Optimistic engineers hope to have the LUVOIR aloft sometime in the 2030s.
The Habitable Exoplanet Imaging Mission
A possible configuration for a telescope launching in the 2050s or later?
As its name suggests, the Habitable Exoplanet Imaging Mission (HabEx) would be a singularly focused piece of machinery.
As currently conceived, HabEx would scan the sky in the optical, ultraviolet and infrared spectrum, looking for signs of Earth-sized worlds with liquid water that are orbiting in the habitable zone of their parent star.
Not to be pegged as a one-trick mission, the HabEx development team is also looking to add relevant scientific investigations to the mission mix. Some of the possible mission goals could be exploring deep stellar archaeologies by resolving star positioning and evolution in dense galactic clusters, further mapping of the UV signature of the Milky Way, and observations of the effects of dark energy.
In the coming year, the initial mission plan for HabEx should be formalized and the telescope will be submitted for review by bean counters. If selected, HabEx will begin the likely decades-long development process.
Looking Deep
While the current state of space telescopes is in a holding pattern, in coming years the James Webb and WFIRST missions will come online and begin delivering valuable insights into the origin of our Universe and the mysteries that still befuddle astronomers and cosmologists. As that data begins to pile up, and discoveries are made, the LSSM’s next telescope should be readying itself for launch and the allure of finding hundreds, if not thousands, of potentially life-supporting planets will be fueling the imaginations of a new generation of researchers.
Needless to say, the search for the answers to our Universe’s origins will continue to fuel the minds of scientists, engineers and laypeople alike, and make it necessary to ready evermore advanced devices for interrogating the cosmos. Hopefully, governments or whatever systems replace them, will keep ponying up the cash for these expensive, albeit invaluable systems.
To live without the answers to the origin of the Universe and an ever better understanding of physics is a fate too depressing to contemplate, a complete disregard for what makes humanity interesting—its incessant need to explore and know.