# Active galactic nuclei imaging programs of the RadioAstron mission

## TL;DR

RadioAstron’s space-VLBI imaging of active galactic nuclei achieves unprecedented angular resolution, revealing detailed jet structures, magnetic fields, and instabilities, advancing understanding of AGN physics.

## Contribution

This paper provides an overview of RadioAstron’s AGN imaging programs, highlighting their innovative high-resolution imaging capabilities and early scientific results.

## Key findings

- Unprecedented angular resolution of a few tens of microarcseconds.
- Detailed imaging of jet collimation and magnetic field configurations.
- Detection of Kelvin-Helmholtz instabilities in AGN jets.

## Abstract

Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key science objectives of the RadioAstron space-VLBI mission. There are three RadioAstron imaging key science programs that target both nearby radio galaxies and blazars, with one of the programs specifically focusing on polarimetry of the jets. The first images from these programs reach angular resolution of a few tens of microarcseconds and reveal unprecedented details about the jet collimation profile, magnetic field configuration, and Kelvin-Helmholtz instabilities along the flow in some of the most studied AGN (3C 84, BL Lac, 3C 273, S5 0836+710). Here we give an overview of the goals and strategy of these three ongoing programs, highlight their early results, and discuss the challenges of space-VLBI imaging.