Daily Current Affairs - 09-05-2021

The remains of Chinese rocket have crashed into the Indian Ocean. It is said to have been hurtling towards the earth. Hurtling is moving in a high speed, especially in a wildly uncontrolled manner.

What happened?

On April 28, 2021, China launched the Long March 5B rocket. The rocket carried the Tianhe core module of China space station. The Tianhe core module weighed 22.5 tonnes, one of the heaviest space modules. It used its own propulsion to enter in to the orbit. However, the first stage began to decay due to atmospheric drag.

The rocket fell in the Indian Ocean near the Maldives.

Is Tianhe a success or failure?

Failure. There were huge controversies over Tianhe module as China was silent after the launch. No comments were made if the rocket is being controlled. It was even unclear if the project was a success or failure as there were widespread news that only a part of the space module is falling in to the earth. Lack of transparency in such international issues was not welcomed by several countries.

Concerns

The core module launched provided living space for the astronauts. And thus, it was unusually large and heavy. After the failure of the module, it entered into an uncontrolled orbit. As it was heavy, the chances of burning away of the entire module was minimal. A part of heavy chunks were to hit the earth’s surface. However, the Chinese were silent on where the rocket is to hit the earth and when. The tracking of the re-entry was not shared. However, the US and the Europeans predicted that the rocket could hit between 41.5 degrees north and 41.5 degrees south.

Previous massive re-entries

Sputnik V vaccine developed by Russia is a two-dose vaccine. The unique feature of the vaccine is that the first and second dose are different from each other. In Sputnik Light a single dose is sufficient.

Sputnik V

Sputnik V is also known as Gam-COVID-Vac. It uses heterogenous recombinant adenovirus approach. Meaning, Sputnik V is a two-vector vaccine. It uses Adeno Virus 26 in the first dose and Adeno Virus 5 in the second dose. These Adeno Viruses are the carriers.

Conjugate Vaccine

A Conjugate Vaccine is a vaccine that uses a weak antigen with a strong antigen as a carrier. It is informally called a carrier vaccine. Sputnik V is a Conjugate Vaccine.

Why a double dose earlier?

Adenoviruses are common. They are ubiquitous (commonly found everywhere) in the environment that is contaminated by human faeces or sewage. They cause common cold and fever. This means that Adeno virus is commonly found in the humans. This is one of the main reasons why adeno virus based COVID-19 vaccines are single dose vaccines. However, Sputnik V was a double dose vaccine. This was done to booster the immune response compared to use the same vector twice.

Why a single dose now?

Sputnik V vaccine was sold at 10 USD in other markets. In India it is facing difficulties to compete with AstraZeneca Vaccine, also called COVISHIELD, which is sold at 2 USD per dose. The price of COVISHIELD is low in India as it is manufactured locally by the Serum Institute of India. On the other hand, Sputnik V is imported. It is marketed by Dr Reddy’s Laboratories. Now, to compete with COVISHILED and capture the market, the price has to be reduced, which is, highly impossible as the vaccine is being imported. Thus, a single dose vaccine is being launched. India is planning to launch this single dose vaccine.