Scientific discovery with the James Webb Space Telescope

Abstract

For the past 400 years, astronomers have sought to observe and interpret the Universe by building more powerful telescopes. These incredible instruments extend the capabilities of one of our most important senses, sight, towards new limits such as increased sensitivity and resolution, new dimensions such as exploration of wavelengths across the full electromagnetic spectrum, new information content such as analysis through spectroscopy, and new cadences such as rapid time-series views of the variable sky. The results from these investments, from small to large telescopes on the ground and in space, have completely transformed our understanding of the Universe; including the discovery that Earth is not the center of the Universe, that the Milky Way is one among many galaxies in the Universe, that relic cosmic background radiation fills all space in the early Universe, that that the expansion rate of the Universe is accelerating, that exoplanets are common around stars, that gravitational waves exist, and much more. For modern astronomical research, the next wave of breakthroughs in fields ranging over planetary, stellar, galactic, and extragalactic science motivate a general-purpose observatory that is optimized at nearand mid-infrared wavelengths, and that has much greater sensitivity, resolution, and spectroscopic multiplexing than all previous telescopes. This scientific vision, from measuring the composition of rocky worlds in the nearby Milky Way galaxy to finding the first sources of light in the Universe to other topics at the forefront of modern astrophysics, motivates the state-of-the-art James Webb Space Telescope (Webb). In this review paper, I summarize the design and technical capabilities of Webb and the scientific opportunities that it enables.

Ring galaxies in the EAGLE hydrodynamical simulations

“…With the upcoming large sky surveys and telescope missions, such as the James Webb Space Telescope (JWST; Gardner et al 2006;Kalirai 2018), the MeerKAT Karoo Array Telescope HI Surveys (Holwerda et al 2012), the Australian Square Kilometre Array Pathfinder HI surveys (Johnston et al 2007(Johnston et al , 2008, the Multi-Unit Spectroscopic Explorer (MUSE; Bacon et al 2010), the K-band Multi-Object Spectrograph (KMOS; Wisnioski et al 2015) surveys, and Atacama Large Millimeter/submillimeter Array (ALMA) future surveys, we expect to be able to study ring galaxies at higher redshifts and larger volumes due to their deep and large sky coverage. Through these surveys, we will also be able to test the simulation predictions and probe both the gas-phase pressure and the metallicity in these galaxies.…”

On the detection of supermassive primordial stars – II. Blue supergiants

“…They found that these objects could be observed today even by 8 − 10 m telescopes on the ground, primarily because of their high surface temperatures (20,000 -30,000 K), larger masses (up to 10 7 M ⊙ ) and longer lives (up to 10 7 yr; see also recent reviews by Freese et al 2016;Banik et al 2019). Most recently, Surace et al (2018) calculated spectra for cool, red SMSs and found that some will be visible to the James Webb Space Telescope (JWST; Gardner et al 2006;Kalirai 2018) at z 20 and at z ∼ 10 -12 to Euclid (Laureijs et al 2011) and the Wide-Field Infrared Space Telescope (WFIRST; Spergel et al 2015) if they are gravitationally lensed. Hartwig et al (2018) also found that the relics of such stars would be uniquely identifiable with the gravitational wave detector LISA at z > 15 if they form in binaries.…”

AGNs at the cosmic dawn: predictions for future surveys from a ΛCDM cosmological model

“…The launch of the James Webb Space Telescope (JWST) in 2021 will pave the way for an increased understanding of the z > 7 Universe (e.g. Gardner et al 2006;Kalirai 2018). JWST, with its 6.5m diameter mirror, will make observations from the optical to mid-infrared (0.6 µm to 30 µm) to probe the earliest galaxies and the stars contained within them.…”