Aditya-L1 solar mission: HEL1OS spectrometer captures first high-energy X-ray view of solar flares

HEL1OS spectrometer aboard Aditya-L1 spacecraft captured its first images of 'solar flares' on October 29. (Image courtesy: Indian Aerospace Defence News/X)

The Indian Space Research Organisation (ISRO) announced on November 7 that the High Energy L1 Orbiting X-ray Spectrometer (HEL1OS), tasked with observing hard X-ray activities from the Sun, successfully recorded first high-energy X-ray images of solar flares during its initial observation period on October 29, 2023.

According to the space agency, the data captured is consistent with the X-ray light curves provided by US’ National Oceanic and Atmospheric Administration’s (NOAA) GOES (Geostationary Operational Environmental Satellites).

HEL1OS: Observing Sun's hard X-ray flares

Designed by the Space Astronomy Group at the U R Rao Satellite Centre, ISRO in Bengaluru, HEL1OS was meant to play a crucial part in the scientific pursuits of the Aditya-L1 Solar Mission, launched on September 2 this year to study the Sun.

Since its commissioning on October 27, 2023, HEL1OS has been consistently observing hard X-ray activities from the Sun. HEL1OS data empowers researchers to delve into and understand phenomena related to explosive energy releases and electron acceleration during the impulsive phases of solar flares.

Aditya-L1 Solar Mission

India achieved a successful launch of its inaugural solar mission, Aditya-L1, from the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh, on September 2.  The spacecraft, as per ISRO, after travelling about 1.5 million km from the Earth over 125 days, would be stationed at Lagrangian point L1, which is considered closest to the Sun, about 1.5 million km from Earth, which is about 1% of the Earth-Sun distance.

As per ISRO, Aditya-L1 constantly faces the Sun throughout its mission duration of around five years. Aditya-L1 will neither land on the Sun nor approach the Sun closer.

Aditya-L1 Objectives

The primary objective of the Aditya-L1 solar mission is to explore the Sun's outer atmosphere, analyze its various phenomena, and investigate how solar winds, radiation, and the Sun's magnetic fields influence Earth.

Upon activation at L1, the payloads will undergo tests to explore the solar atmosphere, coronal mass ejections (CMEs), solar wind acceleration, and other solar activities. This may take another four to six months. Payloads equipped with specialized detectors and devices will directly observe the Sun, capturing data on the photosphere, chromosphere, and the corona layer. These instruments are designed to measure electromagnetic radiation, charged particles, and magnetic fields, furnishing vital insights into issues such as coronal heating, Coronal Mass Ejections, pre-flare and flare activities, and the dynamics of space weather.

Understanding these solar activities holds significant importance as it can safeguard space-based assets, such as communication systems, weather forecasting, and navigation. The mission plays a crucial role in advancing scientists' comprehension of the Sun and its behavior, especially given predictions that the Sun is expected to reach its next peak activity phase around 2025.