Aditya-L1 launch date announced

GS Paper - 3 (Space Technology)

The Indian Space Research Organisation (ISRO) has announced that the Aditya-L1 mission, the first space-based Indian observatory to study the Sun, will be launched on 2 September 2023 from Sriharikota. The spacecraft will be placed in a halo orbit around the Lagrange point 1 (L1) of the Sun-Earth system, which is about 1.5 million km from the Earth.

Where is the Aditya-L1 mission going?

• The spacecraft will be put in orbit around the L1 point, from where it will be able to observe the Sun without obstructions.
• A Lagrange point is a position in space where “the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them.
• These points in space can be used by spacecraft to reduce fuel consumption needed to remain in position.
• Basically, this means that at that point, the gravitational attraction and repulsion between two heavenly bodies is such that an object placed between them will effectively stay in the same relative position while moving with them.
• The Lagrange points are named in honor of Italian-French mathematician Josephy-Louis Lagrange, and there are five of them: L1, L2, L3, L4, and L5.
• The L1 point of the Earth-Sun system affords an uninterrupted view of the Sun and is currently home to the Solar and Heliospheric Observatory Satellite SOHO.

What will the Aditya-L1 mission study?

• The spacecraft carries seven payloads to observe the photosphere [the deepest layer of the sun we can directly observe], chromosphere [the layer about 400 km and 2,100 km above the photosphere], and the outermost layers of the Sun (the corona), using electromagnetic and particle and magnetic field detectors. Of the seven playloads, four will directly study the Sun, and the remaining three will in situ study particles and fields at the Lagrange point L1, thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium.
• “The suits of Aditya L1 payloads are expected to provide the most crucial information to understand the problem of coronal heating, coronal mass ejection, pre-flare and flare activities and their characteristics, dynamics of space weather, propagation of particles and fields etc.

Why is it important to study the Sun?

• Every planet, including Earth and the exoplanets beyond the Solar System, evolves — and this evolution is governed by its parent star. The solar weather and environment affect the weather of the entire system.
• Variations in this weather can change the orbits of satellites or shorten their lives, interfere with or damage onboard electronics, and cause power blackouts and other disturbances on Earth. Knowledge of solar events is key to understanding space weather.
• To learn about and track Earth-directed storms, and to predict their impact, continuous solar observations are needed. Every storm that emerges from the Sun and heads towards Earth passes through L1.

First of its kind data released by Chandrayaan-3

GS Paper - 3 (Space Technology)

India’s Chandrayaan-3 spacecraft has begun releasing important data from the scientific experiments being conducted by the instruments on board. The Indian Space Research Organisation (ISRO) released first-of-its-kind data from the observations made by ChaSTE (Chandra’s Surface Thermophysical Experiment), one of the four instruments on the lander module.

Temperature variation

• The first set of data released by ISRO showed a very sharp difference in temperatures just above and below the surface of the Moon.
• A graphical plot put out by ISRO showed that while temperatures on the surface were over 50 degree Celsius, they dropped to nearly -10 degree Celsius just a few millimetres below the surface.
• The measurements suggested that the topsoil of the lunar surface did not conduct heat very well, and insulated the sub-surface from heat.
• The measurements are consistent with what is known about the thermal profile of the Moon from previous expeditions and experiments.
• But this is the first direct measurement of temperatures of the topsoil and the subsoil near the South Pole of the Moon.
• Temperature variation on the Moon is relatively well-known. Even on the surface, there is a huge difference between day-time and night-time temperatures.
• Some places on the Moon are known to be colder than -200 degree Celsius at night time while others can get hotter than 100 degree Celsius during the day.
• Scientists have been studying the temperature variations on the Moon since the start of the lunar missions in the 1960s and 1970s.
• In addition, samples brought back by the Apollo and other missions have also contributed to this knowledge, as scientists have been able to study their heat-conducting properties.
• Using this information, scientists have built three-dimensional models of the thermal environment on the Moon. It is known that a thin upper layer of the lunar surface, a few cm thick, shows very low thermal conductivity.
• Below that, however, thermal conductivity is high, which means that after a few centimetres of depth, temperature is almost stable and no longer shows a sharp drop. But the picture of the thermal environment is far from complete.
• The kind of observations being made by ChaSTE not just help in validating these existing models, but also provide entirely new insights with exact quantitative measurements.

What is the ChaSTE?

• ChaSTE is meant to study the heat conductivity of the Moon’s surface and measure the differences in temperatures at different points on and below the surface, with the overall objective of creating a thermal profile of the Moon.
• This instrument has been developed by the Space Physics Laboratory at the Vikram Sarabhai Space Centre in Thiruvananthapuram and the Physical Research Laboratory in Ahmedabad.

EU’s new Digital Services Act

GS Paper - 3 (ITC)

The new Digital Services Act (DSA) is a landmark legislation that aims to regulate the online activities of tech giants like Google, Facebook, Amazon, and more, and to create a safer and more transparent internet for everyone.

What is the Digital Services Act?

• Passed by the European Parliament in July 2022, the Digital Services Act (DSA) is a new set of rules that aims to make the online world safer and more transparent for users in the European Union.
• It applies to online platforms that offer goods, services, or content to EU citizens, such as social media, e-commerce, or cloud services.
• The DSA requires online platforms to take measures to prevent and remove illegal or harmful content, such as hate speech, terrorism, child abuse – or those that promote illegal goods.
• Alongside this, DSA also requires that platforms give users the means to report this type of content.
• The Act also prohibits online platforms from using a person’s sexual orientation, religion, ethnicity, or political beliefs as criteria for targeted advertising.
• It also protects children from being exposed to excessive or inappropriate ads by imposing restrictions on ad targeting.
• Furthermore, it mandates online platforms to disclose how their algorithms operate and influence the content they display.
• The DSA has stricter rules for very large online platforms, which are those that reach more than 10% of the EU population (about 45 million users) per month.
• These platforms have to share data with researchers and authorities, cooperate with crisis response requirements, and undergo external and independent audits.
• While smaller platforms aren’t being asked to comply with these regulations just yet, large ones are being asked to comply within 4 months following the agreement on the Act, which was in April.

Why is the Act important for India and other non-EU regions?

• The DSA may have been implemented by the EU for the EU, but its effects may stretch far beyond those continental bounds.
• The EU hopes that the Act will serve as a standard for effective intervention for the protection of fundamental rights online.
• It preserves a balanced approach to the liability of intermediaries, and establishes effective measures for tackling illegal content and societal risks online. In doing so, the DSA aims at setting a benchmark for a regulatory approach to online intermediaries also at the global level.
• Moreover, platforms tend to favour consistent policies that are easier to implement and maintain.
• As a result, the DSA may prompt the platforms to adopt changes that will affect not only the EU, but also other regions.
• For example, the upcoming iPhone 15 series is likely to feature a USB Type-C port worldwide, even though it is only mandated in the EU.