Tag: earth

According Scientists, Earth Have Experienced A Massive Asteroid Strikes 290 Million Years Ago

Experts say the mysterious rise in strikes may have spelled doom for the dinosaurs, who were wiped out by an asteroid around 60million years ago.

It’s perhaps fair to say it was a date with destiny for the dinosaurs,” said study author Dr Thomas Gernon, from the University of Southampton.

Their downfall was somewhat inevitable given the surge of large space rocks colliding with Earth.” Space boffins at the University of Southampton examined asteroid craters on the moon to come to their finding.

Many of Earth’s ancient craters have worn away after millennia of eroding weather and tectonic plate shifts. The moon doesn’t have this problem, meaning its oldest impact holes are still in tact.

Because Earth and its neighbour have been hit by the same proportion of asteroids over time, scientists can date the moon’s craters to understand more about our own.




For the new study, experts tracked the age of the moon’s craters using images and thermal data from Nasa’s Lunar Reconnaissance Orbiter (LRO) space probe.

If a crater gives off more heat, it means it is younger because it is surrounded by larger boulders.

Over millions of years, these boulders break down into fine moon dust that comes up cold on the LRO’s heat cameras.

Scientists studied craters formed in the past billion years, and found there were fewer before 290 million years ago.

In fact, the rate of crater formation since then has been two to three times higher than in the previous 700 million years.

It’s unclear what caused the jump, but scientists think it may be linked to massive collisions taking place in the asteroid belt before 290 million years ago.

This could have created a mass of debris that has since rained down on other parts of the solar system.

The team say asteroid strikes probably played a massive role in Earth’s big extinction events, including the destruction of the dinosaurs.

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Pass it on: New Scientist

Going up? Space Elevator Could Possibly Take Astronauts Into Space

A Canadian space firm is one step closer to revolutionizing space travel with a simple idea – instead of taking a rocket ship, why not take a giant elevator into space?

Thoth Technology Inc has been granted both US and UK patents for a space elevator designed to take astronauts up into the stratosphere, so they can then be propelled into space.

The company said the tower, named the ThothX Tower, will be an inflatable, freestanding structure complete with an electrical elevator and will reach 20km (12.5 miles) above the Earth.

Astronauts would ascend to 20km by electrical elevator. From the top of the tower, space planes will launch in a single stage to orbit, returning to the top of the tower for refueling and reflight,” Brendan Quine, the tower’s inventor, said in a statement.

Traditionally, regions above 50km (31 miles) in altitude can only be reached by rocket ships, where mass is expelled at a high velocity to achieve thrust in the opposite direction.

Quine said in the patent that rocketry is “extremely inefficient” and that a space elevator would take less energy.




In the patent, Quine explained that rocket ships expend more energy because they “must counter the gravitational force during the flight by carrying mass in the form of propellant and must overcome atmospheric drag”.

In contrast, by using an elevator system, “the work done is significantly less as no expulsion mass must be carried to do work against gravity, and lower ascent speeds in the lower atmosphere can virtually eliminate atmospheric drag”.

The elevator cars can also be powered electrically or inductively, eliminating the need to carry fuel, Quine wrote.

The technology offers a way to access space through reusable hardware, and will save more than 30% of the fuel of a conventional rocket, Thoth Technology said in a July statement.

Quine said when a traditional rocket ship launches from Earth, it flies vertically about 15-25km (9-15 miles) before hitting drop-off stages, when sections of the rocket drop back to Earth, usually falling into the ocean.

During the final stage when it enters space it is flying horizontally.

An elevator to space has been a longstanding idea as an alternative to rocket ships, but has always been believed as unfeasible because no known material can support itself at such a height.

Thoth’s design sidesteps this problem by building the elevator to 20km so it sits within the stratosphere rather than all the way in the geostationary orbit, where satellites fly.

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China Makes Historic First Landing on Mysterious Far Side of the Moon

Humanity just planted its flag on the far side of the moon.

China’s robotic Chang’e 4 mission touched down on the floor of the 115-mile-wide (186 kilometers) Von Kármán Crater Wednesday night (Jan. 2), pulling off the first-ever soft landing on the mysterious lunar far side.

Chang’e 4 will perform a variety of science work over the coming months, potentially helping scientists better understand the structure, formation and evolution of Earth’s natural satellite.

But the symbolic pull of the mission will resonate more with the masses: The list of unexplored locales in our solar system just got a little shorter.




The epic touchdown—which took place at 9:26 p.m. EST (0226 GMT and 10:26 a.m. Beijing time on Jan. 3), according to Chinese space officials—followed closely on the heels of two big NASA spaceflight milestones.

On Dec. 31, the OSIRIS-REx spacecraft entered orbit around the near-Earth asteroid Bennu, and the New Horizons probe zoomed past the distant object Ultima Thule just after midnight on Jan. 1.

Congratulations to China’s Chang’e 4 team for what appears to be a successful landing on the far side of the moon. This is a first for humanity and an impressive accomplishment!”

NASA Administrator Jim Bridenstine said via Twitter Wednesday night, after word of the milestone began circulating on social media.

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NASA’s First Up-Close Images Of The Most Distant Object Ever Explored

NASA’s New Horizons’ team released the first close-up images from Ultima Thule on Wednesday afternoon.

Even at the speed of light, signals from the outer solar system take a long time to reach Earth; however, the pictures were well worth the wait.

They reveal Ultima Thule is actually two objects stuck together. That’s prompted them to dub the big lobe “Ultima” and the small one “Thule.”

And while the first images may still be a bit disappointing, the best pictures will be arriving in the days and weeks ahead.

We have far less than one percent of the data that’s stored on [New Horizons],” spacecraft lead Alan Stern of the Southwest Research Institute said at a press conference Wednesday.




New Year’s flyby

As billions of people across the world ushered in the new year, the New Horizons spacecraft whizzed by a far-flung space rock named Ultima Thule, making it the most distant object ever visited by humanity.

Traveling at a speed of nearly 9 miles (14.5 kilometers) per second, New Horizons’ didn’t take long to zip past Ultima Thule, which is only about 20 miles (30 km) long and 10 miles (15 km) wide.

During its closest approach at 12:33 a.m. EST on January 1, New Horizons passed within just 2,200 miles (3,500 km) of the mysterious bowling-pin-shaped rock, collecting data all the while.

Within just 10 hours, at 10:28 a.m. EST, the spacecraft successfully “phoned home,” confirming to NASA scientists that it had survived its close encounter with the distant object.

Since New Horizons sent its first post-flyby message, the mission team slowly but surely has been receiving a trickle of data on Ultima Thule (pronounced TOOL-ee, a Latin phrase meaning “a place beyond the known world”), which is located a staggering 4.1 billion miles (6.6 billion km) from Earth.

What we know so far

Ultima Thule is tiny, icy body known as a Kuiper Belt Object (KBO). KBOs are a distinct class of solar system objects that lie far beyond the orbits of Neptune and Pluto.

Although over a thousand KBOs already have been discovered Ultima Thule wasn’t found until 2014.

Because Ultima Thule is so small and distant, it’s very hard for researchers to tease out many of its attributes, even with the most advanced telescopes available today.

But from early on, astronomers figured the small body was likely made of dirty ice and rock.

Early observations of Ultima Thule taken by New Horizons suggested that the rock is rather elongated and shaped somewhat like a bowling pin.

Today’s imagery reveal that the world is actually two objects which were stuck together in a slow cosmic collision.

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Incredible First Ever Image Of What The Sun’s North Pole Looks Like

What does the north pole of the Sun look like?

This might not be one of the most pressing questions in astronomy, but it has been intriguing solar physicists for a while.

We’ve sent many probes to study the Sun at a wide range of latitudes but never actually from above or below, so there’s a gap in our knowledge of our star, which we may now be able to start filling in.

Using data from the Proba-2 (PRoject for OnBoard Autonomy 2) observatory, the European Space Agency (ESA) has managed to create an image of how the north pole of the Sun is likely to look.

So, without directly photographing it, how did they do it?

Proba-2 focuses mainly on the lower latitudes of the Sun but it captures everything in its line of sight, including solar atmospheric effects at high latitudes, which can indirectly help us understand the polar regions.




The team took observations of the Sun, blocking out the solar disk, and leaving only the northernmost part (and a bit on the sides) – as demonstrated by this handy comic strip-style illustration below.

These were converted into information about the atmospheric situation at the time the image was taken.

The process was then repeated several times at later times until there was enough data to cover roughly half of a solar rotation. And from that, they were able to reconstruct the image above.

Such a reconstruction is not certainly a true image – some imprecisions are evident, such as the big line across the middle, which is due to changes to the solar atmosphere as the observations were taking place – but it is the best we can hope for, for now.

Dark and light patches are seen on the surface, indicating that the complexity of our star extends to all latitudes. The dark patch in the middle is a polar coronal hole, the source of a fast solar wind.

The image is from extreme ultraviolet light, so it tracks the energetic processes that give rise to the solar wind, the particles that stream from the Sun out into the Solar System.

The network of structure seen here could alter the solar wind speed.

The NASA/ESA Ulysses mission back in 1994/1995 was the only probe we’ve sent to study the polar regions of the Sun, but It won’t be the last. ESA is planning to send a new mission in 2020.

The Solar Orbiter will study the Sun at high enough latitudes that it will be capable of exploring its polar regions.

This knowledge will be very important in understanding several processes happening on the Sun’s surface and how they impact the space environment around Earth.

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Scientists Are Expecting The 1st Direct Black Hole Image Soon

In late 2017, scientists with the Event Horizon Telescope – an international collaboration that’s created a virtual Earth-sized telescope, with the goal of capturing the first direct image of a black hole – reported on a the long-awaited shipment of hard disk drives from the South Pole.

They said they were busily analyzing the data on these drives, which is expected to be a key component in giving us the first-ever direct image of a black hole sometime in 2019.

As most of us know, black holes are truly black. That is, they are regions containing so much mass squeezed into so little space – regions of such powerful gravity – that no information or light or anything can escape, even if moving at the fastest speed known to exist in our universe, the speed of light.

Astronomers with the Event Horizon Telescope aren’t aiming to capture the black nothingness of a black hole itself (that’s not possible), but instead a black hole’s event horizon, the sphere-like point-of-no-return surrounding a black hole.




Which black hole then? Naturally, they’ll want to image the black hole that appears biggest from Earth.

The first logical choice is Sagittarius A* – pronounced Sagittarius A-star – a 4-million-solar-mass black hole located at the center of our home galaxy, the Milky Way.

This supermassive black hole is about 27,000 light-years from Earth.

The secondary target of the Event Horizon Telescope is much, much farther away, some 50-60 million light-years from Earth.

It’s the supermassive black hole at the center of M87: the largest galaxy in our home galaxy cluster, the Virgo cluster.

How can it appear big to us, at such a great distance away? It contains over 6 billion solar masses. This black hole is so big it could swallow our solar system whole.

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The Story Behind Our Planet’s Most Famous Photo

 

The crew of the Apollo 8 spacecraft (Bill Anders, 3rd left) following the lunar orbital mission, 27 December 1968.

This photograph is now half a century old. It was taken by the astronaut Bill Anders on Christmas Eve 1968 as the Apollo 8 spacecraft rounded the dark side of the moon for a fourth time.

When Earth came up over the horizon, Anders scrabbled for his Hasselblad camera and started clicking.

In that pre-digital age, five days passed. The astronauts returned to Earth; the film was retrieved and developed.

In its new year edition, Life magazine printed the photo on a double-page spread alongside a poem by US poet laureate James Dickey: “And behold / The blue planet steeped in its dream / Of reality, its calculated vision shaking with the only love.”

This was not quite the first look at our world from space. Lunar probes had sent back crudely scanned images of a crescent Earth shrouded in cloud.

A satellite had even taken a colour photo that, in the autumn of 1968, the radical entrepreneur Stewart Brand put on the cover of his first Whole Earth Catalog.

The next edition, in spring 1969, used Anders’s photograph, by now known as Earthrise.




Brand’s catalogue was a DIY manual for the Californian counterculture, a crowdsourced compendium of life hacks about backpacking, home weaving, tantra art and goat husbandry.

Its one-world, eco ethos was a weird offshoot of the macho tech of the space age – those hunks of aluminium run on rocket fuel and cold war rivalries.

But then looking back at Earth was itself a weird offshoot of the moon missions.

It just happened that Apollo 8’s aim – to locate the best lunar landing sites – needed high-res photography, which was also good for taking pictures of planets a quarter of a million miles away.

When Bill Anders took this photograph from the Apollo spacecraft on Christmas Eve in 1968, our relationship with the world changed forever

The Earth pictured in Earthrise looks unlike traditional cartographic globes that mark out land and sea along lines of latitude and longitude.

Slightly more than half the planet is illuminated. The line dividing night and day severs Africa. Earth looks as if it is floating alone in the eternal night of space, each part awaiting its share of the life-giving light of the sun.

Apart from a small brown patch of equatorial Africa, the planet is blue and white. At first glance it seems to have the sheen of blue-veined marble.

But look closer and that spherical perfection softens a little. Earth divulges its true state as oceanic and atmospheric, warmly welcoming and achingly vulnerable.

The Apollo 8 crew (from left) Frank Borman, James Lovell and Bill Anders

The blue is light scattered by the sea and sky. The white is the gaseous veneer that coats our planet and lets us live.

You can just make out the “beautiful blue halo”, with its gentle shift from tender blue to purple black, that Yuri Gagarin noticed on his first low-orbit flight.

That halo is our fragile biosphere, and is all that stands between us and the suffocating void.

Still, Earthrise must have changed something. What’s seen can’t be unseen. Perhaps it flits across your mind when you open Google Earth and see that familiar virtual globe gently spinning.

The non-human version of Earthrise from Lunar Orbiter in 1966.

Just before you click and drag to fly yourself to some portion of the world no bigger than an allotment, you may briefly take in, with a little stomach lurch, that this slowly revolving sphere holds close to 8 billion people, living out lives as small and short and yet meaningful as the universe is infinite and eternal and yet meaningless.

On that gigantic, glistening marble, mottled with blue-white swirls, lies everyone.

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Will an asteroid hit Earth? Frequent Asteroid Questions (FAQ)

Should I be worried about asteroids hitting Earth?

No, and yes. You shouldn’t lose sleep over it because damaging asteroids do not hit very often.

But you should care about it: they have hit and dangerous asteroids will hit again, unless we prevent that from happening—which we can if we put in the work to find, track, characterize asteroids, develop methods to deflect dangerous asteroids, and internationally coordinate and educate.

What is an asteroid, exactly?

An asteroid is a small, rocky or metallic object orbiting the Sun. They are now usually defined as being larger than 1 meter in diameter with objects smaller than that being called meteoroids.

The largest asteroid is Ceres at 965 km (600 mi) diameter. Most asteroids, including Ceres, are located in the asteroid belt between Mars and Jupiter, but some asteroids come near to or cross Earth’s orbit.

How do asteroids form? Where do asteroids come from?

Asteroids are typically material left over from the period of planetary formation 4.5 billion years ago, the stuff left over that didn’t form into planets in the inner solar system.  Often they are fragments of collisions between asteroids in the past.




How many near-Earth asteroids are there?

Using the cut-off for asteroid diameter of 1 meter, there are estimated to be more than half a billion near-Earth asteroids.

For objects that cause major damage if they hit Earth (larger than about 30 meters), there are about a million. So far, we are approaching 20,000 found.

It is easier to find larger objects, so we think we have found more than 90% of the asteroids 1 km and above, but for smaller asteroids still capable of causing major regional damage, we have only found a small percentage.

Are there any asteroids heading for Earth?

There are a few asteroids that currently are known to have a low probability of hitting Earth in tens to hundreds of years.

What are near-Earth objects and how could they affect us?

For example, one of the highest probabilities currently is an approximately 37 meter diameter asteroid called 2000 SG344 that has a 1 in 1100 chance of impact in 2071.

But these always are based on asteroid observations that have uncertainties in them. Usually, as more observations are obtained, the impact probability will drop to 0; in other words we know it won’t hit.

JPL keeps an online list of all asteroids with any probability of hitting Earth.

The big uncertainty is that we haven’t discovered most of near Earth asteroids yet, so we don’t know if they are on a collision course with Earth, which is why finding and tracking them is crucial.

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NASA Craft Shows Tiny Asteroid Studded With Boulders

NASA’s first look at a tiny asteroid shows the space rock is more moist and studded with boulders than originally thought.

Scientists released the first morsels of data collected since their spacecraft Osiris-Rex hooked up last week with the asteroid Bennu, which is only about three blocks wide and weighs about 80 million tons.

Bennu regularly crosses Earth’s orbit and will come perilously close in about 150 years. There is no liquid water on the asteroid, but there is plenty of it in the form of wet clay.

Project scientist Dante Lauretta of the University of Arizona said the blueish space rock is “a little more rugged of an environment than we expected” with hundreds of 10-metre boulders, instead of just one or two.

There’s also a bigger 50-metre boulder which looks like two cones put together with a bulge on its waistline.

Scientists think Bennu is a leftover from the beginning of the solar system 4.5 billion years ago when planets tried to form and some failed.

Mr Lauretta said it looks like Bennu was once a chunk of a bigger asteroid that probably had water in it.




When Osiris-Rex starts orbiting Bennu in January — no easy feat since its gravity is 100,000 times less than Earth’s — it will be the smallest object that a human-made spacecraft has circled.

Scientists will spend a year scouting the space rock for a good location and then in 2020 it will dive close to the surface and a robotic arm will shoot nitrogen puffs into the soil and collect grains of dirt.

Those asteroid bits will be returned to Earth in 2023.

The 800 million dollar (£636 million) Osiris-Rex mission began with a 2016 launch from Cape Canaveral, Florida. Its odometer read 1.2 billion miles last week.

The spacecraft and asteroid names come from Egyptian mythology. Osiris is the god of the afterlife, while Bennu represents the heron and creation.

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NASA Probe Arrives at Asteroid Bennu on Monday

I hope you’re not all partied out after the InSight lander’s successful touchdown on Mars this week, because there’s another big spaceflight event just around the corner.

NASA’s OSIRIS-REx probe will officially arrive at the near-Earth asteroid Bennu at about 12 p.m. EST (1700 GMT) today, Monday (Dec. 3), ending a 27-month deep-space chase.

NASA will mark the occasion with a special webcast event from 11:45 a.m. to 12:15 p.m. EST (1645 to 1715 GMT), which you can watch live here at Space.com, courtesy of NASA TV.

The space agency will also air an “arrival preview program” at 11:15 a.m. EST (1615 GMT). You can catch that here at Space.com as well.

The $800 million OSIRIS-REx mission launched on Sept. 8, 2016, embarking on a looping trek toward the 1,640-foot-wide (500 meters) Bennu.

Upon arrival, the probe will take up a position about 12 miles (20 kilometers) from the space rock, NASA officials said.

OSIRIS-REx will then fly by Bennu repeatedly over the next four weeks, gathering data that will help mission team members establish the asteroid’s mass.

With this information in hand, OSIRIS-REx will slide into orbit around the space rock on Dec. 31 — just hours before NASA’s New Horizons probe cruises past the distant object Ultima Thule, billions of miles from Earth.




The diamond-shaped Bennu will then become the smallest object ever to be orbited by a spacecraft.

OSIRIS-REx will study the rock from orbit for the next 18 months or so and then make its way down to Bennu’s surface to grab a sizeable sample of material in mid-2020.

The spacecraft will depart the asteroid in March 2021, and the sample will come down to Earth in a special return capsule in September 2023.

Scientists around the world will study this material, looking for clues about the role that carbon-rich asteroids such as Bennu may have played in bringing the building blocks of life to Earth.

OSIRIS-REx — which is short for “Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer” — will also make significant contributions in other ways, mission team members have said.

For example, the probe’s measurements should help researchers better understand the resource potential of Bennu-like space rocks.

And other data will increase knowledge of how asteroids move through space, which in turn should improve predictions of where hazardous rocks are headed.

Bennu is itself a potentially dangerous asteroid; there’s a very small probability that it could hit Earth in the late 22nd century.

OSIRIS-REx isn’t the only active asteroid-sampling mission. Japan’s Hayabusa2 spacecraft is currently orbiting the 3,000-foot-wide (900 m) Ryugu, which shares Bennu’s diamond shape.

Hayabusa2 will grab a Ryugu sample next year and return it to Earth in late 2020, if all goes according to plan.

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