SCIENCE
The most feared asteroids that could potentially hit Earth
There are 1,167,079 asteroids classified by Esa (European Space Agency) as of March 8, 2023, of which there is good orbital information, almost all in the belt between Mars and Jupiter. Among them there are 1,449 that are potentially dangerous, that is, with a probability of impact on our planet that is either very small or very remote in time, but cannot be considered zero.
What are the ten most dangerous according to Esa (full list here)? Leading the way is 2023DW, of which there is one chance in 700 that it may come to collide with Earth.
These are all very small objects, up to an estimated 400 meters in diameter, the vast majority with diameters of a few tens of meters. Then there are two larger objects, including the asteroid Bennu, placed on a special list because, given their size, they are much more threatening.
The current situation
There are 1,167,079 asteroids classified by Esa (European Space Agency) as of March 8, 2023, of which there is good orbital information, almost all in the belt between Mars and Jupiter. Among them there are 1,449 that are potentially dangerous, that is, with a probability of impact on our planet that is either very small or very remote in time, but cannot be considered zero.
The most dangerous
Which are the ten most dangerous according to Esa. At the top is 2023DW, of which there is a one in 700 chance that it could collide with Earth. In second place there is 2001VB, apparently much more dangerous because the date of the close encounter is next 23 July (at 9.16 a.m. Italian time), but the probability of impact is only 1 in 356 million, really low.
Small but no less dangerous
They are all very small objects, up to an estimated 400 meters in diameter, with the vast majority being only a few tens of meters in diameter. This does not mean that these "orbiting rocks" should not be monitored carefully. Even Nasa has its own list of potentially hazardous asteroids (which it calls Neo, Near-Earth Objects). These include Pho (Potentially Hazardous Objects), with diameters of 140 meters or more
A comparison
For comparison, Arizona's Meteor Crater (pictured) was formed 50-60 thousand years from the impact of a 100-meter diameter metallic asteroid that caused a 180-meter deep hole with a diameter of 1,300 meters.
The most recent example
The one that exploded 30 kilometers high above the Siberian skies of Chelyabinsk (pictured) on Feb. 15, 2013 caused about 1,500 light injuries from shattered glass shards due to the air displacement of the explosion with an energy comparable to that of 35 atomic bombs like the one in Hiroshima. That asteroid was 20 meters in diameter and weighed 13,000 tons.
The Bennu asteroid
Then there are two larger objects, including the Bennu asteroid(pictured), placed on a special list because, given their size, they are much more threatening even though the dates of their eventual impacts are shifted several centuries into the future. After new studies, the most likely impact date of Bennu has been placed on Sept. 24, 2182 with a 1 in 2,700 probability, or 99.963% chance that it will pass close to us but without any devastating impact.
How to defend ourselves
Space agencies have initiated several experimental programs. According to scientists, launching a nuclear-tipped missile at an asteroid would serve little. The best idea is to deflect, albeit slightly, its orbit. Basically, push it a little to the side. On September 26, 2022, Nasa's Dart mission succeeded for the first time in changing the orbit of Dimorphos, a small rock orbiting the Dydimos asteroid, proving that this system can be successful.
The imminent future
In 2026, Nasa will launch the new infrared space telescope Neos (Near-Earth Object Surveyor), which will be tasked with facilitating the detection of these potential threats. Esa is planning the Neomir mission in 2030, with the same goals.So what is the next one that will pass us by? It is 2020FV4, a 30-meter-diameter "rock" that transited yesterday Monday, March 13 but 6.7 million kilometers away. Today there will be 2023CM a full 190 meters in diameter. But it will transit 3.94 million kilometers away.
science
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The Six Degrees of Separation Theory, which assumes that each person can be connected to any other in the world through a chain of knowledge with no more than five intermediaries, is one of the most popular and suggestive social theories ever created, and may still be valid today in the age of social networking.
It was in the mid-1960s when a Harvard professor sent a letter to an unknown farmer in Nebraska, hoping that, through a completely random network of contacts, the letter would reach its true recipient in Boston.
Today, a study co-ordinated by the Institute of Complex Systems of the National Research Council in Florence (CNR-Isc) - signed by researchers from Spain, Israel, Russia, Slovenia and Chile - has shown that connections on social networks resemble those found by Milgram in the 1960s.
Art galleries private collections
25/03/2024
In Islam, the ḥajj is the traditional pilgrimage to the Holy Mosque in Mecca; it constitutes the fifth pillar of Islam. The pilgrimage is performed during the Dhū l-Ḥijja which is, in the Islamic calendar, the twelfth month of the year, of 29 or 30 days. In 2023, the pilgrimage is performed in the last days of June (Western calendar).
It is a pilgrimage that every Muslim is obliged to make on a compulsory basis, provided he or she has the means, first of all financial, and then physical. To date, hundreds of thousands of faithful have already celebrated the 'Tawaf of Advent', seven walks around the Kaaba, the black stone cube covered by the kiswa, an Italian silk cloth, embroidered in gold by Saudi artisans.
The significance, for followers of Islam, is to retrace the journey of Ibrahim and Ismail, i.e. Abraham and his son Ishmael in Christian and Jewish traditions.
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Art galleries private collections
Art galleries private collections