The Disturbed and quiet time Ionosphere-thermosphere System at High Altitudes (DISHA) is a proposed twin satellite

aeronomy Aeronomy is the scientific study of the upper atmosphere of the Earth and corresponding regions of the atmospheres of other planets. It is a branch of both atmospheric chemistry and atmospheric physics. Scientists specializing in aeronomy, know ...

mission by the

Indian Space Research Organisation The Indian Space Research Organisation (ISRO ) is India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), ...

. It will study the effects of

space weather Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the varying conditions within the Solar System and its heliosphere. This includes the effects of the solar wind, especially on the Earth's magnetosphere, ion ...

events on the uppermost layers of

Earth's atmosphere The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weathe ...

. The mission will consist of two small satellites namely DISHA-H and DISHA-L in high and low inclinations for simultaneous observation in polar and equatorial regions. DISHA satellites will have expected mission life of 5 years with at least 3 years of combined operations and are expecting readiness by 2024–25.

Payloads

DISHA-H and DISHA-L are similar in configuration with six common payloads each. But while DISHA-L has all of its six scientific payloads on fixed platform, DISHA-H has an additional scientific payload called Auroral X-ray Imaging Spectrometer (AXIS) and all seven of them are positioned on a rotatable deck to meet data transmission requirements. * Neutral Mass Spectrometer (NMS) by Space Physics Laboratory (SPL) to measure neutral composition (1-300 amu) with 10° FOV * Airglow Photometer (AP): Narrow bandwidth (0.03 nm) photometer by PRL with 3° FOV to measure nightside

airglow Airglow is a faint emission of light by a planetary atmosphere. In the case of Earth's atmosphere, this optical phenomenon causes the night sky never to be completely dark, even after the effects of starlight and diffuse sky radiation, diffuse ...

emissions in two wavelengths (630 nm, 777.4 nm). * Drift meter: Ion drift meter with retarding potential analyser (1 to 40 amu) by PRL and SAC with 45° FOV. * Auroral X-ray Imaging Spectrometer (AXIS) by URSC and PRL is nadir facing soft X-ray spectrometer (0.3 to 2 KeV) with 110° FOV and 5 km resolution. * High frequency Langmuir probe (LP): Two novel high frequency Langmuir probes developed by PRL to measure electron density and fluctuations. In double mounted configuration One probe will perform the sweep and other will monitor plasma potential. * Electron Temperature Analyser (ETA) by SPL * Upper Atmosphere Visible Airglow Spectral Imager (UrVASI) by SPL, by SAC and

IIT Roorkee The Indian Institute of Technology Roorkee (IIT- Roorkee or IIT-R) is a technical university located in Roorkee, Uttarakhand, India. It is the oldest engineering institution in India. It was founded as the College of Civil Engineering in 1847 d ...

to measure nightglow emission from 80 to 500 km altitude range (2 km resolution) in two channels (585 to 595 nm, 530-780nm with 0.1 nm, 0.5 nm resolution) and 12° FOV

References

{{Future spaceflights Satellites of India