When Japan’s Hayabusa mission traveled to asteroid Itokawa, it collected samples. These successfully reached Earth in 2010.
Near Earth asteroid Itokawa is a rubble pile that formed more than four billion years ago, a new study found. So, these asteroids might be resilient to demise.
Destroying an Earth-killing asteroid is not always possible, here’s what we can do instead.
Do you know what size asteroid would be enough to end all life on Earth? According to the experts at NASA, a space rock only 96 km wide can do the job.
In 2005, for the first time, a Japanese space capsule Hayabusa brought the dust particles of an asteroid named Itokawa to Earth.
Sixty-six million years ago, the age of the dinosaurs came to a dramatic close as a huge asteroid impact accelerated them on a path towards extinction. Not all of them died out, however; those that survived went on to become today’s birds.
Scientists are still trying to carefully map out the anatomical changes that occurred between dinosaurs and birds during this time, and there’s arguably no better way to do this than to engage in a little “reverse evolution.” With this in mind, a team of researchers has grown “dinosaur legs” in chicken embryos, as revealed in their study in the journal Evolution.
Remarkably, previous research manipulating chickens into “becoming” dinosaurs has already taken place. Back in 2015, a study showcased that chickens that had been tweaked during embryonic development could grow a dinosaur-like snout. A year earlier, a more low-tech study demonstrated how a few strategically-placed weights could make a chicken walk along like a Tyrannosaurus rex.
The NEO Surveyor will be able to detect individual asteroid heat signatures.
NEO Surveyor is, as the name implies, a satellite specifically designed to survey objects near the Earth (NEO). One of its primary contributions will be to look for asteroids and other small bodies that are potentially on an eventual collision course with Earth but are invisible to typical NEO survey missions because of their location in the solar system.
Typically, their signals are just background noise against the overwhelming signal from the Sun. But NEO Surveyor will be able to detect individual asteroid heat signatures, allowing it to isolate potentially dangerous asteroids using this novel technique. With the increased focus on “planetary defense,” as it has come to be called, NASA has been interested in the mission, which was initially proposed in 2005, for some time.
Forged 66 million years ago, an enormous impact crater near Chixculub, Mexico, was left undiscovered until only a few short decades ago. But what caused it?
Millions of years ago, a dramatic mass extinction wiped out the dinosaurs.
Marking the transition between the Mesozoic and Cenozoic eras (which we are still in), it was one of the most significant events in Earth’s history. The cause? Perhaps a giant asteroid hit Chixculub near modern-day Yucatan, Mexico.
Sixty-six million years ago, something from the very edge of our solar system completed its unlikely journey into the inner planets.
The event is likened to the Chicxulub collision on Earth.
A study has found that the megatsunami that swept Mars around 3.4 billion years ago was caused by an asteroid strike on one of its oceans. The event is compared to the likes of the Chicxulub collision—which is believed to have wiped out dinosaurs from the face of the earth about 66 million years ago.
Researchers, led by Alexis Rodriguez of the Planetary Science Institute in Arizona, have also suggested that NASA’s Viking 1 Lander, which was deployed on a mission to find evidence of life on Mars in 1976, could have landed near the crater of this megatsunami.
Michalz86/iStock shannonstent/iStock Dominic Jeanmaire/iStock.
We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion – life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind.
A team of researchers at the University of Copenhagen’s Center for Star and Planet Formation, working with colleagues from Université de Paris, ETH Zürich and the University of Bern, has found evidence suggesting that most of the water that made up an ancient global ocean on Mars came from carbon-rich chondrite meteorites from the outer solar system. The study is published in Science Advances.
Prior research has suggested that at one time, Mars was either mostly or entirely covered by a watery ocean, and that the water came from gases seeping from below the surface and liquifying as they cooled. In this new effort, the researchers suggest the water more likely came from another source—meteorites traveling from the outer solar system.
The researchers came to this conclusion after studying fragments flung from the surface of Mars after asteroid strikes, which made their way to Earth as meteorites. The researchers studied 31 of them, looking most specifically for chromium isotopic fingerprints. Chromium-54 does not occur naturally on Mars; thus, its presence in crust samples from Mars would indicate that the surface had been struck by material from somewhere else.
Microbial life may have resided within the first four kilometers of Mars’s porous crust.
Four billion years ago, the solar system was still young. Almost fully formed, its planets were starting to experience asteroid strikes a little less frequently. Our own planet could have become habitable as long as 3.9 billion years ago, but its primitive biosphere was much different than it is today. Life had not yet invented photosynthesis, which some 500 million years later would become its main source of energy. The primordial microbes — the common ancestors to all current life forms on Earth — in our planet’s oceans, therefore, had to survive on another source of energy.
Some of the oldest life forms in our biosphere were microorganisms known as “hydrogenotrophic methanogens” that particularly benefited from the atmospheric composition of the time. Feeding on the CO2 (carbon dioxide) and H2 (dihydrogen) that abounded in the atmosphere (with H2 representing between 0.01 and 0.1% of the atmospheric composition, compared to the current approximate of 0.00005%), they harnessed enough energy to colonize the surface of our planet’s oceans.
In return, they released into the atmosphere large amounts of CH4 (a.k.a., methane, from which they get their name), a potent greenhouse gas that accumulated and heated up the climate. Since our sun at the time was not as bright as it is today, it may not have been able to maintain temperate conditions on the planet’s surface without the intervention of other aspects. As such, thanks to these methanogens, the very emergence of life on Earth may itself have helped ensure our planet’s habitability, setting the right conditions for the evolution and complexification of the terrestrial biosphere for the billions of years that followed.
