New studies find the interstellar comet 2I/Borisov is the most "pristine" ever discovered.
One of the only interstellar visitors ever discovered traversing our Solar System, the rogue comet 2l/Borisov, is also one of the most "pristine" such space objects ever. The comet, which was first spotted in 2019 by the amateur Ukrainian astronomer Gennady Borisov, likely never flew too close to any star including our sun, which left its composition very similar to how it was upon formation.
Comets, which are space bodies made of frozen gas, rock, and ice, are usually impacted by the heat and radiation they encounter on their way. What's attractive to scientists in studying comets that haven't changed much in their lifetimes is that they have a similar composition to the gas and dust that was present at the formation of the Solar System 4.5 billion years ago. Analyzing pristine comets can lead to a deeper understanding of the Solar System's beginnings and evolution.
The 2I/Borisov comet is only the second interstellar object ever found in our Solar System. The first one was 1I/'Oumuamua, detected in 2017.
The new study, based on observations from the European Southern Observatory's Very Large Telescope (ESO's VLT) in Chile, was led by Stefano Bagnulo of the Armagh Observatory and Planetarium in Northern Ireland.
"2I/Borisov could represent the first truly pristine comet ever observed," said Bagnulo.
The 2I/Borisov interstellar comet captured with the VLT.Credit:ESO/O. Hainaut
As reported in Nature Communications, his team used a technique called polarimetry, which measures the polarization of light, to study the space body. This helped the team compare 2I/Borisov to other local comets. The properties of the new comet were quite different from others they found in the Solar System, except for Hale-Bopp, a comet discovered in 1995 which is also considered very pristine.
The study's co-author Alberto Cellino from the Astrophysical Observatory of Torino, Italy, commented upon this connection, arrived at by analyzing polarization along with the comet's color:
"The fact that the two comets are remarkably similar suggests that the environment in which 2I/Borisov originated is not so different in composition from the environment in the early Solar System.".
In a fascinating nod to just how powerful Earth's top telescopes have become, another set of ESO researchers published a different study in Nature Astronomy on the comet's composition using data from the Atacama Large Millimeter/submillimeter Array (ALMA). This team, led by astronomer Bin Yang, was able to gather many clues about 2I/Borisov's makeup from its coma – the envelope of dust surrounding it. Inside the coma, they discovered compact pebbles, grains around one millimeter in size. They could also tell that the relative amounts of carbon monoxide and water in the comet changed significantly as it came closer to the Sun.
This indicated to them that the materials in the comet came from different places in the cosmos. Matter in the comet's home star system was likely mixed in a discernible pattern that related to how far the comet was from its star, found the scientists. This was possibly affected by the presence of giant planets, which stirred up materials in their system through strong gravity. Astronomers think this kind of process also took place in the early period of the Solar System's life.
"Imagine how lucky we were that a comet from a system light-years away simply took a trip to our doorstep by chance," remarked Yang.
In 2029, the European Space Agency plans to launch the Comet Interceptor project that would allow scientists to study comets that speed through our Solar System with even greater precision.
Scientists find routes using arches of chaos that can lead to much faster space travel.
- Researchers discovered a route through the Solar System that can allow for much faster spacecraft travel.
- The path takes advantage of "arches of chaos" within space manifolds.
- The scientists think this "celestial superhighway" can help humans get to the far reaches of the galaxy.
Humanity could be making its way through the Solar System much faster thanks to the discovery of a new superhighway network among space manifolds. Don't get your engines roaring along this "celestial autobahn" just yet, but the researchers believe the new pathways can eventually be used by spacecraft to get to the outer reaches of our Solar System with relative haste.
The celestial highway could get comets and asteroids from Jupiter to Neptune in less than a decade. Compare that to hundreds of thousands or even millions of years it might ordinarily take for space objects to traverse the Solar System. In a century of travel along the new routes, a 100 astronomical units could be covered, project the scientists. For reference, an astronomical unit is the average distance from the Earth to the Sun or about 93 million miles.
The international research team included Nataša Todorović, Di Wu, and Aaron Rosengren from the Belgrade Astronomical Observatory in Serbia, the University of Arizona, and UC San Diego. Their new paper proposes a dynamic route, going along connected series of arches within so-called space manifolds. These structures, coming into existence from gravitational effects between the Sun and the planets, stretch from the asteroid belt to past Uranus.
The most pronounced of these structures are linked to Jupiter by its strong gravitational pull, explained UC San Diego's press release. They influence the comets around the gas giant as well as smaller space objects called "centaurs," with are like asteroids in size but exhibit the composition of comets.
This animation shows space manifolds over a hundred years. Each frame of the animation shows how the arches and substructures appear over three-year increments.
Credit: Nataša Todorović, Di Wu and Aaron Rosengren/Science Advances
"Space manifolds act as the boundaries of dynamical channels enabling fast transportation into the inner- and outermost reaches of the Solar System," write the researchers. "Besides being an important element in spacecraft navigation and mission design, these manifolds can also explain the apparent erratic nature of comets and their eventual demise."
A closer image of the manifolds showing colliding and escaping objects.
Credit: Science Advances
The researchers discovered the structures by analyzing collected numerical data on the millions of orbits in the Solar System. The scientists figured out how these orbits were contained within known space manifolds. To detect the presences and structure of the space manifolds, the team employed the fast Lyapunov indicator (FLI), used to detect chaos. The scientists ran simulations to compute how the trajectories of particles approaching different planets like Jupiter, Uranus and Neptune would be affected by possible collisions and the manifolds.
While the results are encouraging, the next step is to figure out how these arches can be used by spacecraft for much speedier travel. It's also not clear how similar manifolds work near Earth. Also unclear is how they impact our planet's run-ins with asteroids and meteorites or any of the man-made objects floating up in space near us.
Check out the new paper "The arches of chaos in the Solar System" in Science Advances.
The solar system has some strange stuff in it. Learning how it ended up that way can tell us where we're going.
- A new model of Saturn's atmosphere might finally explain how a bizarrely shaped storm developed there.
- The model produced a polygonal storm system similar, but not identical to, that observed on Saturn.
- The findings may shed light on the formation of the solar system.
The Solar System has some strange stuff in it. Uranus rotates on its side, Venus turns backward, Mercury is shrinking, Neptune radiates away far more heat than it gets from the sun, and Saturn has a hexagonal shaped storm at its north pole.
In their never ending attempt to understand the cosmos, scientists have dedicated a fair amount of time to these topics. Now, after years of speculation, a new article published in Proceedings of the National Academy of Sciences may finally explain the source of Saturn's bizarrely shaped storm.
First noticed in the 1980s by the passing Voyager spacecraft and later observed by the Cassini–Huygens mission, the storm is an estimated 29,000 km (18,000 mi) wide with sides 2,000 km (1,200 mi) longer than the diameter of the Earth. It has been known to change color, from blue to gold, and rotates with the same period as Saturn's natural radio emissions. No similarly shaped storm exists at the south pole, though a storm vortex has been seen there.
No similar storm is known to exist anywhere.
To determine how the storm takes on its unique shape, Harvard Professor and Jeremy Bloxham and research associate Rakesh K. Yadav created a model of Saturn's atmosphere that simulates the planet's outer layer. Running the simulation for a month, they found that the movement of heat could cause massive polar storms and a robust eastward jet stream. When these phenomena combine, they form the peculiar shape in an attempt to share the same space.
The study's lead author Rakesh K. Yadav explained what is happening to Phys.org:
"This jet is going around and around the planet, and it has to coexist with these localized [smaller] storms. Imagine we have a rubber band and we place a bunch of smaller rubber bands around it and then we just squeeze the entire thing from the outside. That central ring is going to be compressed by some inches and form some weird shape with a certain number of edges. That's basically the physics of what's happening. We have these smaller storms and they're basically pinching the larger storms at the polar region and since they have to coexist, they have to somehow find a space to basically house each system. By doing that, they end up making this polygonal shape."
Their model also suggested that the storms are forming very deep in Saturn's atmosphere, a potential reason why it has endured as long as it has without a significant change in shape or intensity. Debate continues on how far down the storm goes. While this study does lend weight towards the stance that it extends very far, perhaps thousands of kilometers, into the Saturnian atmosphere, the model was limited to simulating surface and near-surface activity.
Further refinement of the model will be needed to settle this debate.
It must also be pointed out that what the model created wasn't a hexagon but a nine-sided polygon (a nonagon) that rotated at a different rate than the storm on Saturn. Despite this, the scientists argue that this is a proof of concept which supports the central thesis on how such a strangely shaped storm can come into existence and endure for longer than four decades.
Why this matters on Earth
Figuring this out can also help shed light on Saturn's formation as, by extension, the formation of the solar system. As Yadav explains:
"From a scientific point of view, the atmosphere is really important in determining how quickly a planet cools. All these things you see on the surface, they're basically manifestations of the planet cooling down and the planet cooling down tells us a lot about what's happening inside of the planet. The scientific motivation is basically understanding how Saturn came to be and how it evolves over time."
Understanding how the solar system came into being can help us not only understand how other star systems might work but also help us determine how our solar system, including Earth, will change in the future. So even if you don't have to worry about a hexagonal storm anytime soon, you may someday benefit from the attempt to understand how such a thing could ever exist.
This meteorite is the oldest known volcanic rock in the solar system, dated at 4,565,000,000 years old.
- It's very rare that we discover something on our planet that was around before we were even a small speck. But every once in a while, we do—and this meteorite is a living testament.
- Scientists estimate the new discovery to be approximately 4.6 billion years old, almost as old as the solar system itself.
- New discoveries like this one bring us a small step closer in piecing together what an earlier version of Earth might have looked like.
For thousands of years, humans were completely unaware of the existence of the solar system. They believed that Earth was the center of the universe.
We have since been proven very wrong. Scientists have discovered that the solar system was created when a supernova exploded and the resulting gas and dust combined around 4.6 billion years ago.
How exactly our planet was formed still remains a mystery.
What is the discovery, and why is it important?
This meteorite is the oldest known volcanic rock in the solar system, dated at 4,565,000,000 years old.
Photo: University of New Mexico
Northwest Africa (NWA) 11119 is a small, baseball-sized rock. It's formed from sparkly green meteorite and has an unusual light green fusion crust. Broken fragments of the interior have revealed bright green and grey crystals that are up to 3mm in size. Scientists expect that it is approximately 4.6 billion years old, almost as old as the solar system itself.
The rock was acquired by a meteorite dealer in Mauritania, Africa, in 2016. It weighs 453g, and it is currently located at the Maine Mineral and Gem Museum.
For those who don't know much about meteorites, distinguishing between a terrestrial rock and an actual meteorite can be challenging. To make matters worse, there are many sellers who try to disguise terrestrial rocks as meteorites to scam their customers.
Many people are surprised that meteorites can actually be bought, sold, and collected outside of museums and labs. However, since the invention of the Internet, there has been a surge in the number of collectors and dealers.
eBay is actually one of the most popular websites for people to buy and sell meteorites. However, before using such websites, it is important that you take the required precautions and buy from reputable dealers. For example, websites like Meteorite Exchange has a page that summarizes the listings from known dealers in order to help buyers make more informed decisions.
To make the process of buying and selling meteorites safer, meteorite dealers are often hired to confirm that what the customer is buying is an actual meteorite (this means it came from space) and not just a rock.
At first glance, this meteorite didn't look like much
When the rock was first found, the planetary geologist and meteorite curator at the University of New Mexico, Carl Agee, didn't think that it was a meteorite at all. In fact, he thought it was a rock from Earth.
He then passed it on to his doctoral student, Poorna Srinivasan, to examine it.
Despite the rock bearing a close resemblance to volcanic rocks on Earth, its chemical composition revealed that it was definitely from space and that it wasn't just a regular meteorite.
What is special about the meteorite?
Skeleton of a tridymite crystal.
NWA 11119 was revealed to be 4.6 billion years old. This makes it the oldest igneous meteorite (meaning that it was formed by the cooling and solidification of either magma or lava) ever discovered. Scientists have discovered several non-igneous meteorites that are even older than this.
About 30% of the meteorite is comprised of tridymite, which are essentially large silica crystals. Such a high tridymite content is virtually unheard of in meteorites. It's comparable to the levels found in volcanic rocks on Earth.
How often do we come across things that are older than Earth?
It's easy to see why this discovery is so exciting. It's not very often that we come across things that are older than our planet—but there have been a couple of instances over the past few years.
In fact, analysis of NWA 11119 has revealed that it has a strong chemical resemblance to two other known unusual meteorites: NWA 7235 (discovered in 2011), and Almahata Sitta (discovered in 2008). The link is strong enough to suggest that all three of these space rocks could potentially have originated from the same parent body.
In November 2015, geologists working in outback South Australia recovered a primordial meteorite from Kati Thanda-Lake Eyre. This meteorite was thought to be a chondrite or stony meteorite and serves as an example of the material that was created when the solar system was being formed over 4.5 billion years ago.
What's more, as little as a couple of months ago, scientists discovered stardust particles on Earth that are even older than our solar system. Its chemical composition, which shows us how far the particles had traveled, suggested that the grains had to be significantly older than 4.6 billion years.
What happens next?
There is still so much we have yet to understand about how planets are formed, and in particular, how the Earth's crust might have been formed.
However, every once in a while, new discoveries like this one bring us a small step closer in piecing together what an earlier version of Earth might have looked like. Over the past few years, scientists have even discovered frozen meteorites in the Antarctic.
Hopefully one day we might be able to collect enough pieces of such evidence to come to a reasonable conclusion.
Cryovolcanoes that eject ice instead of magma have been confirmed to exist on Ceres, which will help studying this formation on other planets and moons throughout the solar system.
- Cryovolcanoes that ooze out ice instead of shooting out magma have been confirmed to exist on the asteroid Ceres.
- Scientists believe that ice volcanoes may be prevalent throughout the solar system in places like Titan and Pluto.
- Further research is needed to find out if they serve an important function for planetary structure and exo geological systems.
When we think of volcanoes we often picture plumes of smoke and hellfire lava. These are the molten towers from the underworld. But new research has uncovered that ice volcanoes or cryovolcanoes are also just a stone's throw away in our own solar system. We don't have to go that far to look for strange features of the universe. These mountainous giants spew ice instead of fire and are active planetary features that many moons, planets and asteroids might all possess.
Scientists recently analyzed images of Ceres, an asteroid 588 miles wide and one of the largest asteroids in our asteroid belt. NASA's dawn spacecraft flew by and found that Ceres is one of the first confirmed celestial bodies to have multiple cryovolcanoes. A large mountain structure called Ahuna Mons was first discovered in 2016 and subsequently classified as a cryovolcano.
It's estimated that Ceres forms a new cryovolcano every 50 million years. Studying this asteroid will give scientists more evidence to look for and study Europa, Titan and Pluto to see if they also have cryovolcanoes.A paper published in Nature Astronomy detailed the findings. Scientists from the project stated:
"Ceres is the only plausibly cryovolcanic world to be orbited by a spacecraft up to now."
Science of a cryovolcano
Researchers behind the study looked at images taken by the spacecraft's onboard camera. They searched for any exo geological features that were dome shaped and larger than 10 kilometers in diameter. Scientists found and measured 22 of these features and found that these domes were composed of 50 percent of ice. On further analysis, it was found that on average these cryovolcanoes on Ceres spewed out roughly 10 thousand cubic meters per year of ice.
It was determined that a cryovolcano on Ceres doesn't serve an important function say compared to volcanic activity on Earth. But that doesn't rule out that other planet's with cryovolcanoes might be function as an important part to the geological pressures and planetary structural systems.
There were some limitations to the study, as this was all researched through pictures and there wasn't an on the ground rover or robotic presence. Also the scientists weren't able to get a real time reading of the amount of activity each cryovolcano produced.
Cryovolcano on Pluto? Maybe.
Planetary scientist Michael Sori, utilized calculations made from observations and simulations to uncover the mystery about Ceres's cryovolcanoes. His theory was that since Ceres is both made out of predominantly rock and ice, the formations on the planet flow and move due to their own weight – similar to how glaciers operate on Earth. The ice flows would then be affected by slight temperature variations throughout the asteroid.
"Ceres' poles are cold enough that if you start with a mountain of ice, it doesn't relax… But the equator is warm enough that a mountain of ice might relax over geological timescales."
It was observed through simulation with the set parameters that cryovolcanoes on the poles would remain frozen while places in the equator and other latitudes, a cryovolcano would begin to steepen and also grow rounder over time.
Volcanic eruptions on Ceres are much more subdued than what you'd see on Earth. They do not explode, but rather ooze. This output of ice, rock and other chemicals slowly seeps from the openings out onto the rest of the asteroid.
Further research will help yield answers to determine if other suspected formations on other planets and moons may also be cryovolcanoes. After scientists from NASA's New Horizons mission stitched together a high resolution color view of Pluto, it was thought that an area known as Wright Mons may be a cryovolcano. At 150 kilometers across and 4 kilometers high, it'd be one of the largest in the far reaches of the solar system – proving that this phenomenon is not rare
Are there any cryovolcanoes on earth?
There are no cryovolcanoes on earth. The material that erupts out of these formations is either in the form of an icy liquid or gas. Earth simply is too warm for this type of formation to occur, even in the deepest reaches of Antarctica or Greenland, it wouldn't be possible. The higher surface temperature on Earth combined with its thick atmosphere makes it unable to freeze volatiles that would include Nitrogen, Methane and carbon dioxide for example.
Overall, the processes on other astral bodies make them more conducive spots for hosting a cryovolcano.