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The existence of Earth’s Trojan asteroids is not well constrained and represents a major gap in our inventory of small bodies in near-Earth space. Their discovery would be of high scientific and human interest.
Scientific outreach involving people with disabilities does not require specific techniques for specific conditions. An inclusive approach involving complementary senses not only helps those with disabilities but everyone else as well.
Canadian astronomers and facilities have had a significant impact in wide-field astronomy. With community planning exercises underway this looks set to continue, with new capabilities and international collaborations in the near future.
The surface of Mars has been well mapped and characterized, yet the subsurface — the most likely place to find signs of extant or extinct life and a repository of useful resources for human exploration — remains unexplored. In the near future this is set to change.
The masses of supermassive black holes, key to many cosmological studies, are highly uncertain beyond our local Universe. The main challenge is to establish the spatial and kinematic structure of the broad-line emitting gas in active galactic nuclei.
The detection of a gravitational-wave background at nanohertz frequencies can tell us if and how supermassive black holes merge, and inform our knowledge of galaxy merger rates and supermassive black hole masses. All we have to do is time pulsars.
Intermediate-mass black holes (BHs) in local dwarf galaxies are considered the relics of the early seed BHs. However, their growth might have been impacted by galaxy mergers and BH feedback so that they cannot be treated as tracers of the early seed BH population.
