Shobhit Mahajan - Frail Blue Dot: Vision of danger from space // NASA says 400 pieces of debris in orbit, India’s ASAT test increased risk to ISS by 44%

On December 18, 2018, around noon local time, a huge fireball was reported at a remote spot over the Kamchatka peninsula, in the Russian far east. Since the location is very remote, there were no visual reports of the explosion and after, but monitoring stations set up worldwide to detect nuclear explosions recorded the low-frequency sound waves caused by this cataclysmic event. The event was also captured by cameras on a Japanese weather satellite.

The explosion was caused by the burning of a meteor 10 metres in diameter, weighing more than 1,400 tonnes and moving at more than 100,000 kph which burnt itself at a height of around 25 km in the atmosphere. The energy released by the event is estimated to be equivalent to around 170 kilotons of TNT. To get a perspective on this number, the total energy released in the atomic bombing of Hiroshima was about 10 times smaller.

Pale blue dot - Earth captured in rare photograph from Saturn spacecraft Cassini

Chicxulub asteroid impact: Stunning fossils record dinosaurs' demise

When this 12km-wide object slammed into what is now the Gulf of Mexico, (at approximately 40,000 mph) it would have hurled billions of tonnes of molten and vaporised rock into the sky in all directions - and across thousands of kilometres.

Meteors hitting the earth are a common phenomenon - remember those wishes made when one spotted a shooting star? A shooting star is a meteor, a rock from space which burns itself in the earth’s atmosphere. They are relatively benign objects that bombard our earth from outer space, classed as meteoroids, which burn in the atmosphere, releasing energy in the form of shockwaves, light and heat. Meteoroids and their much larger cousins, asteroids, orbit the sun. They are remnants from the material that formed our planets. If a small asteroid or a large meteoroid survives its path through the atmosphere and impacts the ground, it is called a meteorite.
Asteroids can vary in size from about a metre across to Ceres, the largest known asteroid which has a diameter of around 1,000 km. Most of them are made of rock but can also contain metals like iron and nickel as well as water and various gases. In fact, the earliest iron used by humans on earth was almost certainly meteoritic in origin. All of this space debris orbits around the Sun. A majority of the asteroids reside in the asteroid belt between Mars and Jupiter. However, some asteroids, prosaically called Near-Earth objects, have orbits which are close to the earth’s orbit, some of them even crossing it. And sometimes they do land on earth, with devastating consequences... read more:
https://www.firstpost.com/india/frail-blue-dot-vision-of-danger-from-space-6351751.html

Posts on Saturn

NASA says 400 pieces of debris in orbit, India’s ASAT test increased risk to ISS by 44%
India's Mission Shakti: NASA administrator says: "That is a terrible, terrible thing to create an event that sends debris at an apogee that goes above the International Space Station. These activities are not sustainable or compatible with human spaceflight."
Days after Prime Minister Narendra Modi announced that India had successfully tested an anti-satellite missile and destroyed a low-orbiting microsatellite, a NASA administrator Tuesday called it a “terrible thing”, and said it was “unacceptable” as it has increased the dangers for astronauts aboard the International Space Station by 44 per cent.

With Mission Shakti, India is now among the world’s advanced space powers and is only the fourth country after the US, Russia and China with the strategic capability to hit and destroy satellites.

Addressing a town hall, NASA administrator Jim Bridenstine said the agency has identified “400 pieces of orbital debris” after India shot down a microsatellite. “That’s what has been identified, but all of that cannot be tracked. We are tracking about 60 pieces right now — these are objects that are 10 cm or bigger. Of these 60, we know that 24 of them are going above the apogee of the International Space Station,” he said.

Adding that the event led to new risks for astronauts aboard the International Space Station, Bridenstine said, “We’re learning more and more every hour that goes by about this orbital degree field that has been created by the ASAT test. Since last week, the risk of small debris impact to the ISS has increased by 44 per cent.” He, however, added that the astronauts and the ISS are safe and “if we need to manoeuvre it (the debris), we will.”

https://indianexpress.com/article/india/nasa-says-400-pieces-of-debris-in-orbit-indias-asat-test-increased-risk-to-iss-by-44-5653898/