Nasa feared giant asteroid had 20pc chance of hitting Earth
Nasa feared the chances of a deadly asteroid hitting Earth could rise past 20 per cent, but now believe it is more likely to collide with the Moon.
The '2024 YR4' space rock, which is thought to be up to 90 metres in diameter – almost the length of a football pitch – was spotted on Christmas Day by a telescope in Chile, and its risk of impact rose steadily through January.
Last week, Nasa increased the impact odds of the space rock to 3.1 per cent – or a one-in-32 chance of striking Earth in December 2032.
But a statistical analysis seen by The Telegraph showed that the US space agency had warned that in a 'worst-case scenario' the chance of collision could climb past 20 per cent by April.
The UN-endorsed space mission planning advisory group warns that 'terrestrial preparedness planning' should begin if the probability of impact is greater than 10 per cent within the next 20 years.
The Nasa projections, submitted during a meeting of the International Asteroid Warning Network (IAWN) in Vienna, reveal just how seriously the agency was taking the threat.
Latest observations show that 2024 YR4 is no longer a threat to Earth. However, the chance of it hitting the Moon has now risen to one in 55 (1.8 per cent), with the risk expected to increase in the coming weeks.
A spokesman for Nasa said: 'There still remains a very small chance for asteroid 2024 YR4 to impact the Moon.
'When first discovered, asteroid 2024 YR4 had a very small, but notable chance of impacting our planet in 2032.
'As observations of the asteroid continued to be submitted…experts at Nasa Jet Propulsion Laboratory's centre for near-earth object studies were able to calculate more precise models of the asteroid's trajectory and now have found there is no significant potential for this asteroid to impact our planet for the next century.'
An asteroid of similar size to 2024 YR4 collides with Earth every few thousand years and would be of sufficient size and speed to cause loss of life and severe damage to property.
Astronomers had rated the threat of the new asteroid as being a level three on the Torino impact hazard scale and 'capable of causing localised destruction'.
Nasa said the scare had provided an 'invaluable opportunity' to test planetary defence and notification processes.
The agency said it will continue to observe 2024 YR4 and the James Webb space telescope will also study the rock throughout March to gain more insights.
The asteroid will swing past Earth again in 2028, when final observations can be made ahead of the 2032 pass.
The odds of a collision with Earth currently stand at one in 37,000 (0.0027 per cent) – but its new calculated trajectory means the chance of it hitting the Moon is rising.
'No longer a major impact threat'
Dr Vishnu Reddy, IAWN manager, said: 'The object is no longer a major impact threat. So we are good. Based on what I have seen in the past, it is unlikely to go up higher once it is trending down towards nought per cent.
'The Moon impact probability is up now and will go higher for a few weeks before that comes down as well.'
In recent years the threat from asteroids led Nasa and the European Space Agency (Esa) to crash a spacecraft into an asteroid in the first ever test to see if a space rock could be moved in orbit. Data showed that the mission did change the trajectory.
Esa said that it expected the threat to the Moon to rise in the coming months, before falling.
A spokesman said: 'We do not calculate the impact probability (IP) for the Moon in the same rigorous manner, as for the Earth. However, indeed we still see an upward trend of the Moon IP, which is currently around 1.8 per cent
'The situation is similar as it was when Earth was still well within the uncertainty region.
'The most likely outcome is that also the Moon IP will peak at some point and then start to drop quickly.
'Whether this will happen during the current visibility period, or whether we will have to wait for the next measurement opportunities in 2028, remains to be seen.'
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Scottish Sun
2 hours ago
- Scottish Sun
Distant moon could have aliens on it – and experts just spotted a ‘mysterious motion' in its atmosphere
A DISTANT moon in our solar system might mirror Earth's seasons, according to scientists, who also believe it could be a candidate for finding nearby alien life. And scientists just spotted a mysterious motion in its atmosphere. Advertisement 6 Titan is the only moon in our solar system with a significant atmosphere, making it a top candidate for exploration Credit: NASA / ESA / IPGP / Labex UnivEarthS / University Paris Diderot illustration Titan, Saturn's largest moon, is home to sprawling rivers and lakes of liquid methane, icy boulders and dunes of grains that resemble coffee grounds. It even has an ocean hiding beneath its surface. Some 746million miles (1.2billion kilometers) away from Earth, the distant moon is thought to have rain clouds just like Earth. Unlike seasons on Earth, Titan has a much longer seasonal cycle, with each year on the moon lasting nearly three decades on our planet. Advertisement Despite its brutally cold temperatures, which average around -179C (-290F), this strange, alien world appears to have the organic ingredients for life. Titan is the only moon in our solar system with a significant atmosphere, making it a top candidate for exploration. Nasa's $3.35billion (£2.48billion) Dragonfly mission to Saturn's moon is set to explore the possibility of past or present water-based life, particularly in subsurface oceans and liquid reservoirs. The mission just passed its critical design review - meaning engineers can begin building the helicopter-like robot ahead of its scheduled launch in July 2028. Advertisement Dragonfly, which was officially selected as a viable mission in 2019, is expected to reach Titan sometime in 2034. 6 Nasa's $3.35billion (£2.48billion) Dragonfly mission to Saturn's moon is set to explore the possibility of past or present water-based life Credit: NASA/Johns Hopkins APL/Steve Gribben 6 Dragonfly, which was officially selected as a viable mission in 2019, is expected to reach Titan sometime in 2034 Credit: Johns Hopkins APL 'Strange' motion In late May, researchers found that Titan's hazy atmosphere wobbles like a gyroscope in line with its seasons, as opposed to spinning in line with its surface. Advertisement The "strange" motion was detected following analysis of archival infrared data gathered by Cassini probe. "The behavior of Titan's atmospheric tilt is very strange," Dr. Lucy Wright, a postdoctoral researcher at the University of Bristol, said at the time. "Titan's atmosphere appears to be acting like a gyroscope, stabilising itself in space. "We think some event in the past may have knocked the atmosphere off its spin axis, causing it to wobble. Advertisement "Even more intriguingly, we've found that the size of this tilt changes with Titan's seasons." 6 In late May, researchers found that Titan's hazy atmosphere wobbles like a gyroscope in line with its seasons, as opposed to spinning in line with its surface Credit: SWNS But understanding how the atmosphere wobbles with the seasons is crucial for calculating the landing trajectory of Dragonfly. The rotorcraft will be carried by Titan's fast-moving winds as it descends through the atmosphere. Advertisement Winds on Titan's upper atmosphere can be tempestuous, with speeds reaching up to 270mph (430kmph). Near the surface, however, the winds are much weaker. The tilt of the planet affects how Dragonfly's payload - a suite of scientific instruments designed to search for alien life - will be carried through the air. So research into the atmospheric motion can help engineers better predict where Dragonfly will touch down on the lunar surface. Advertisement 6 A 3D illustration of the hydrocarbon lakes on Titan Credit: Getty 6 Saturn's moon Titan could harbor life, but only a tiny amount, a new study found Credit: NASA/JPL-Caltech Food for thought There appears to be plenty of organic material on Titan to support alien lifeforms, according to a study published in The Planetary Science Journal last month. Its lakes and its subsurface ocean believed to be 300miles deep, is thought to be filled with cold, oily methane and ethane - which is organic material. Advertisement "There has been this sense that because Titan has such abundant organics, there is no shortage of food sources that could sustain life," Antonin Affholder, of the University of Arizona and lead author of the paper, said in a statement. The world exceeds even Earth's oil reserves. However, scientists remain skeptical, and while Titan could harbour life, it's likely only to be a small amount. "We point out that not all of these organic molecules may constitute food sources, the ocean is really big," added Affholder. Advertisement "And there's limited exchange between the ocean and the surface, where all those organics are, so we argue for a more nuanced approach." All you need to know about planets in our solar system Our solar system is made up of nine planets with Earth the third closest to the Sun. But each planet has its own quirks, so find out more about them all... How old is Earth? Plus other facts on our planet How many moons does Mercury have? What colour is Venus? How far away is Mars to Earth? And other facts on the red planet How big is Jupiter? How many moons does Saturn have? Does Uranus have rings? How many moons does Neptune have? How big is Pluto? How hot is the Sun?
The Sun
2 hours ago
- The Sun
Distant moon could have aliens on it – and experts just spotted a ‘mysterious motion' in its atmosphere
A DISTANT moon in our solar system might mirror Earth's seasons, according to scientists, who also believe it could be a candidate for finding nearby alien life. And scientists just spotted a mysterious motion in its atmosphere. 6 Titan, Saturn's largest moon, is home to sprawling rivers and lakes of liquid methane, icy boulders and dunes of grains that resemble coffee grounds. It even has an ocean hiding beneath its surface. Some 746million miles (1.2billion kilometers) away from Earth, the distant moon is thought to have rain clouds just like Earth. Unlike seasons on Earth, Titan has a much longer seasonal cycle, with each year on the moon lasting nearly three decades on our planet. Despite its brutally cold temperatures, which average around -179C (-290F), this strange, alien world appears to have the organic ingredients for life. Titan is the only moon in our solar system with a significant atmosphere, making it a top candidate for exploration. Nasa's $3.35billion (£2.48billion) Dragonfly mission to Saturn's moon is set to explore the possibility of past or present water-based life, particularly in subsurface oceans and liquid reservoirs. The mission just passed its critical design review - meaning engineers can begin building the helicopter-like robot ahead of its scheduled launch in July 2028. Dragonfly, which was officially selected as a viable mission in 2019, is expected to reach Titan sometime in 2034. 6 6 'Strange' motion In late May, researchers found that Titan's hazy atmosphere wobbles like a gyroscope in line with its seasons, as opposed to spinning in line with its surface. The "strange" motion was detected following analysis of archival infrared data gathered by Cassini probe. "The behavior of Titan's atmospheric tilt is very strange," Dr. Lucy Wright, a postdoctoral researcher at the University of Bristol, said at the time. "Titan's atmosphere appears to be acting like a gyroscope, stabilising itself in space. "We think some event in the past may have knocked the atmosphere off its spin axis, causing it to wobble. "Even more intriguingly, we've found that the size of this tilt changes with Titan's seasons." 6 But understanding how the atmosphere wobbles with the seasons is crucial for calculating the landing trajectory of Dragonfly. The rotorcraft will be carried by Titan's fast-moving winds as it descends through the atmosphere. Winds on Titan's upper atmosphere can be tempestuous, with speeds reaching up to 270mph (430kmph). Near the surface, however, the winds are much weaker. The tilt of the planet affects how Dragonfly's payload - a suite of scientific instruments designed to search for alien life - will be carried through the air. So research into the atmospheric motion can help engineers better predict where Dragonfly will touch down on the lunar surface. 6 6 Food for thought There appears to be plenty of organic material on Titan to support alien lifeforms, according to a study published in The Planetary Science Journal last month. Its lakes and its subsurface ocean believed to be 300miles deep, is thought to be filled with cold, oily methane and ethane - which is organic material. "There has been this sense that because Titan has such abundant organics, there is no shortage of food sources that could sustain life," Antonin Affholder, of the University of Arizona and lead author of the paper, said in a statement. The world exceeds even Earth's oil reserves. However, scientists remain skeptical, and while Titan could harbour life, it's likely only to be a small amount. "We point out that not all of these organic molecules may constitute food sources, the ocean is really big," added Affholder. "And there's limited exchange between the ocean and the surface, where all those organics are, so we argue for a more nuanced approach."
The Independent
4 hours ago
- The Independent
Mystery of the dark markings on Mars could finally be solved
Mysterious dark streaks on Mars, observed since the 1970s, are likely due to wind and dust activity rather than water, according to new research. Researchers used a machine learning algorithm to analyze 500,000 streaks from over 86,000 NASA Mars Reconnaissance Orbiter images, creating a global Martian map. The study found that recurring slope lineae (RSLs) are not associated with factors suggesting liquid or frost, but rather with above-average wind speed and dust deposition. Older slope streaks likely form when dust slides off slopes due to seismic activity, winds, or meteoroid impacts, appearing near recent impact craters. The findings cast doubt on the interpretation of slope streaks and RSLs as habitable environments, suggesting a dry origin of formation.
