To a large extent, the Iranian National Observatory (INO) is an answer to a long-standing national request for a modern, world-class facility for astronomy satisfying the observing needs of the community of astronomers and physicists in Iran. At the same time as Iran has large and rich traditions in astronomy, it has, in modern times, been fully without globally competitive tools for observational astronomy. Thus, the national demand and expectations on a national observing facility are high. Nevertheless, INO will also, and importantly, pave the way for Iranian astronomy to recuperate its role in the international scientific community. At the same time as INO will provide Iranian astronomers with competitive observing facilities, it will be offered for use by colleagues from all over the world, thus creating an Iranian international science platform for astronomy. To fulfill its many functions the INO340 science case has a comprehensive nature and covers a wide field of astronomy. A full list of the INO340 science goals is listed below.
Solar System
Our own solar system is a highly interesting example of the rapid advance of modern astronomy and it offers highly interesting samples of a number of important physical parameters. The advent of INO will enable us to tackle long-standing questions concerning the formation of the solar system, the upper layers of the planets’ atmospheres, the physics of the ice and gas giants, and the complex dynamical history of the asteroids and the Kuiper belt objects.
Stars to Stellar Clusters
Together with their counterparts, stars form a large variety of systems. Binary stars are by number the most modest of these systems. Also triple stars, quadruple stars and higher-order smaller stellar systems are abundant everywhere. Larger aggregates of stars are stellar associations, open star clusters and globular star clusters. INO340 is well suited to address many important issues in the vast science of stars.
Extrasolar Planets
Following the first confirmed detection (Mayor and Queloz, 1995) of a planet orbiting a star of solar type, the G2.5Iva star 51 Pegasi, activity in terms of surveys for exoplanets quickly increased in intensity. INO340 will provide an excellent advance in our ability to identify and characterize extrasolar planets.
Interstellar Medium
Stars are fundamental parts of the solar neighborhood and of the Galaxy as a whole as well as of all galaxies. Just like stars, the interstellar medium has an active life. Combined with a high-resolution spectrograph, INO340 would be a very competitive tool for research in the field of interstellar medium.
Galaxies and Their Environments
The study of galaxies and our current understanding of the formation and evolution of the large and small scale structures are to a large extend based on the observations carried out by mid-size telescopes. Some of the interests of the community of astronomers in Iran are highlighted in this section.
Galaxy Groups and Clusters
Galaxy clusters are the largest gravitationally bound systems in the universe. For the community of astronomers in Iran, extragalactic astronomy and observational cosmology is a new undertaking mostly because of the absence of suitable observing facilities. Primarily for this reason INO340 has been funded and pursued.
Dark Matter and Dark Energy
There is a broad agreement that our understanding of galaxy formation and evolution is incomplete. Because the process of galaxy formation is inherently stochastic, among the most important observations are those that involve large statistical samples. INO340 can play an important role in observing such samples.
Time Critical Observations
Time domain astronomy encompasses the study of transient and variable sources. These events are unpredictable, show a temporal evolution of the physical conditions, and often fall below the detection threshold when faint. Such Target of Opportunity transient events generally require a rapid response to a trigger of observations. Time-domain astronomy will be an exciting area of research for INO340.