Science
The Oldest Forest in the World Has Been Discovered in a New York Quarry – VICE
Scientists have discovered the oldest forest in the fossil record at a quarry in the Catskill region of New York. These primordial woods flourished 386 million years ago, during the Devonian period, and contained at least three types of tree, one of which represents a “quantum leap” in plant evolution, according to a study published on Thursday in Current Biology.
The discovery pushes the empirical timeline of forests back millions of years, which has implications for understanding how these trees sparked an “energetic revolution,” meaning that their energy-efficient adaptations reshaped global ecosystems and climate, the authors said.
“The origin of big trees and forests seems to be coincident in time with some dramatic changes in the Devonian ecosystem and climate,” said lead author William Stein, an emeritus professor of biology at Binghamton University, in a call.
“In particular, there’s been pretty clear evidence that there was a drawdown of CO2 levels from the atmosphere during this time,” causing global cooling, he added. “This is important because we’re, in a sense, looking at the opposite trending effects currently with people, deforestation, and global warming.”
The root systems of this Devonian forest are preserved in an abandoned sandstone quarry near Cairo, New York. Though the site has been known for plant fossils since the 1960s, the new specimens were found within the last decade, and may have become noticeable due to years of weathering.
Aerial view of the root systems. Image: William Stein and Christopher Berry
Stein and his colleagues think the fossils represent three ancient tree families: Archaeopteris, Eospermatopteris, and an unidentified species that may have been a type of vascular plant called a lycopsid.
Eospermatopteris, which looked a little like a modern palm tree, was also found at the next oldest fossilized forest, located about 30 miles away in Gilboa, New York. But the real star of the study is Archaeopteris, because it “strikingly advanced for its time” and likely represents “the beginning of the future of modern forests,” Stein said.
“This was a large plant that had modern-looking secondary tissues—basically wood—and it was the first major player that we understand actually had leaves,” he explained. “It’s essentially identical to what you would expect to see today in modern conifers or flowering and seed plants as a whole.”
Unlike Eospermatopteris, which wasn’t able to penetrate very far into the soil with its roots, Archaeopteris grew specialized structural roots that expanded both laterally along the surface of the soil, and deep underground. This robust network could tap into more resources than Archaeopteris’ rivals, and that may explain why it evolved to be such an efficient and innovative photosynthesizer.
Though the Cairo site is a few million years older than Gilboa, Stein said that he shies away from calling it “the oldest forest” because the two sites may have represented one long-lived and relatively stable biome. “That’s our hypothesis: that they probably are just different ecological snapshots of the same longstanding forest,” he said.
Based on the patterns of the sediment, the Gilboa site was likely located in a river system that frequently experienced catastrophic floods, whereas the Cairo area seems to have been drier and less chaotic. Still, the remains of fish inside Cairo’s fossilized forest suggest that it did sometimes flood. These events may have been damaging to the woods at the time, but the sediment upheaval produced by them helped preserve these fascinating fossils.
Stein hopes that future exploration of the Catskills will reveal more clues about the first forests to emerge on Earth, and the role they played in reshaping our planet’s climate and ecology.
“We only have a sample of two sites like this,” he said, “so it leaves a lot to be done in terms of trying to figure out what actually did go on.”
This article originally appeared on VICE US.
The elaborate journey of the robotic spacecraft will offer close encounters with some of the solar system’s least understood objects.
NASA embarked on a 12-year mission to study a group of asteroids on Saturday with the launch of Lucy, a robotic explorer that will meander through the unexplored caverns of deep space to find new clues about the creation of our solar system.
The 5:34 a.m. Eastern time liftoff from Kennedy Space Center in Florida atop an Atlas 5 rocket from United Launch Alliance was the first step of Lucy’s four-billion mile path into the orbital neighborhood of Jupiter. There, two swarms of asteroids known as the Trojans have hid for billions of years, leftover debris from the solar system’s early formation.
The spacecraft launched before dawn, setting off toward the orbit that will begin its elaborate trajectory. Lucy separated from the rocket’s second stage booster roughly an hour after liftoff and about a half an hour later unfurled two circular solar panels that will power the spacecraft throughout its journey.
Orbiting the sun on each side of Jupiter, the two clouds of dark asteroids have only been scrutinized by scientists from afar. Some 10,000 have been identified of the roughly one million that are estimated to exist. Lucy will be the first spacecraft to dive directly into the clusters to get close-up views of seven unique Trojan asteroids, plus one tiny asteroid in the solar system’s main asteroid belt.
“The last 24 hours has just been a roller coaster of excitement and buildup and everything was a success,” Hal Levison, Lucy’s principal investigator, said on a NASA livestream after launch. “We have one chance really to do this, the planets are literally aligning in order to make this trajectory happen.”
He and the mission’s other scientists hope that the sedan-size spacecraft will uncover pieces of evidence about the migration of planets to their current orbits.
What is Lucy?
The Lucy probe, named after the fossilized skeleton of an early hominid ancestor that transformed our understanding of human evolution, will use a suite of scientific instruments to analyze the Trojan asteroids — celestial fossils that the mission’s scientists hope will transform human knowledge about the formation of the solar system.
Managed by the Southwest Research Institute, with a spacecraft built for NASA by Lockheed Martin, the total cost of the mission is $981 million. The spacecraft is roughly the size of a small car and weighs about 3,300 pounds when filled with fuel.
Its scientific instruments include L’TES, or the Lucy Thermal Emission Spectrometer — a telescope designed to scan asteroid surfaces for infrared radiation and measure how quickly or slowly the space rocks’ surfaces heat up and cool down with exposure to the sun’s heat. Built by scientists at Arizona State University, the gadget is essentially an advanced thermometer. Analyzing how quickly the asteroids build up heat gives scientists an idea of how much dust and rocky material is scatted across their surfaces.
Another device is L’LORRI, or the Lucy Long Range Reconnaissance Imager, built by engineers and scientists at the Johns Hopkins Applied Physics Laboratory. This telescope will capture black-and-white images of the asteroids’ surfaces, revealing craters and ridges that have long been shrouded in darkness.
Lucy’s third tool, L’Ralph, has both a color camera and an infrared spectrometer. Each instrument is designed to detect bands of light emitted by ices and minerals scientists expect to be present on the asteroids’ surfaces.
How long is its mission?
Touring the Trojan Asteroids
NASA’s Lucy spacecraft launched this month on a 12-year mission to study the Trojan asteroids, fragments of the early solar system that are now trapped in gravitationally stable areas near Jupiter.
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Jupiter
L4 swarm of
Trojan asteroids
“Greek camp”
L5 swarm of
Trojan asteroids
“Trojan camp”
Orus
2028
Leucus
2028
Patroclus,
Menoetius
2033
Lucy’s
orbital path,
from Jupiter’s
perspective
Polymele
2027
Eurybates
2027
Donaldjohanson
Asteroid flyby in 2025
Earth
at launch
Sun
ASTEROID
BELT
1-year loop
around sun
2021–22
L2
Jupiter
at launch
2-year loop
around sun
2022–24
Jupiter
L1
L4
L5
Sun
Sun
L3
From the sun’s perspective, above, Lucy will make a series of loops toward Jupiter’s orbit, while Jupiter orbits the sun once every 12 Earth years.
Trojan asteroids are clustered around two of Jupiter’s five Lagrange points, where the gravity of the sun and the planet are balanced.
Jupiter
L4 swarm of
Trojan asteroids
“Greek camp”
L5 swarm of
Trojan asteroids
“Trojan camp”
Leucus
2028
Lucy’s
orbital path,
from Jupiter’s
perspective
Orus
2028
Polymele
2027
Patroclus,
Menoetius
2033
Eurybates
2027
Donaldjohanson
Flyby in 2025
Earth
at launch
Sun
ASTEROID
BELT
L2
Jupiter
at launch
Jupiter
L1
L4
L5
Sun
Sun
L3
From the sun’s perspective, above, Lucy will make a series of loops toward Jupiter’s orbit, while Jupiter orbits the sun once every 12 Earth years.
Trojan asteroids are clustered around two of Jupiter’s Lagrange points, where the gravity of the sun and the planet are balanced.
Eurybates
Flyby in 2027
Polymele
2027
Orus
2028
Leucus
2028
L4 swarm of
Trojan asteroids
“Greek camp”
Donaldjohanson
Flyby in 2025
Earth
at launch
Jupiter
ASTEROID
BELT
Sun
Lucy’s orbital path,
from Jupiter’s
perspective
L5 swarm of
Trojan asteroids
“Trojan camp”
Patroclus and
Menoetius
2033
L2
Jupiter
at launch
Jupiter
L1
L4
L5
Sun
Sun
L3
From the sun’s perspective, above, Lucy will make a series of loops toward Jupiter’s orbit, while Jupiter orbits the sun once every 12 Earth years.
Trojan asteroids cluster around two of Jupiter’s Lagrange points, where the gravity of the sun and the planet are balanced.
The spacecraft will spend 12 years hunting down eight asteroids, embarking on an intricate path that uses Earth’s gravity three times to slingshot itself around the sun and through the two swarms of Trojans under Jupiter’s gravitational influence. As it journeys from one side of Jupiter’s orbital path to the other, Lucy will travel roughly four billion miles during its primary mission.
What are the Trojan asteroids?
Lucy’s Targets
The Lucy spacecraft will test its sensors on a small asteroid named after Donald Johanson, discoverer of the Lucy skeleton. The spacecraft will then make six flybys of Trojan asteroids, ranging in size from a tiny moon to a large binary asteroid.
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Donaldjohanson
Flyby in April 2025
Main belt asteroid
Polymele
Sept. 2027
Trojan asteroid
Orus
Nov. 2028
Trojan asteroid
APPROX. 50 MILES
Eurybates
Aug. 2027
Trojan asteroid with
a tiny moon, Queta
Leucus
April 2028
Trojan asteroid
Patroclus
and Menoetius
Flyby in March 2033
Binary Trojan asteroid
Donaldjohanson
Flyby in April 2025
Main belt asteroid
Eurybates
Aug. 2027
Trojan asteroid with
a tiny moon, Queta
Polymele
Sept. 2027
Trojan asteroid
Leucus
April 2028
Trojan asteroid
Orus
Nov. 2028
Trojan asteroid
Patroclus and Menoetius
Flyby in March 2033
Binary Trojan asteroid
APPROX. 50 MILES
Donaldjohanson
Flyby in April 2025
Main belt asteroid
Eurybates
Aug. 2027
Trojan asteroid with
a tiny moon, Queta
Polymele
Sept. 2027
Trojan asteroid
Leucus
April 2028
Trojan asteroid
Orus
Nov. 2028
Trojan asteroid
Patroclus and Menoetius
Flyby in March 2033
Binary Trojan asteroid
APPROX. 50 MILES
The Trojan asteroids are swarms of rocky material left over from the formation of our solar system 4.6 billion years ago. No spacecraft has ever visited the asteroids, which orbit the sun on each side of Jupiter and in the same orbital path, but at a great distance from the giant planet.
Before it gets to the Trojans, it will fly by an asteroid in the main belt between Mars and Jupiter that is named after Donald Johanson, the scientist who discovered the Lucy skeleton. The spacecraft will first visit 52246 Donaldjohanson in April 2025 and will then proceed to its primary destinations.
Lucy will make six flybys of the Trojan asteroids, one of which has a small moon, resulting in seven Trojans visited. The observations should give scientists a diverse set of asteroid material to analyze back on Earth.
What do scientists hope to learn from the Lucy mission?
The Trojan asteroids have been hidden in darkness and nearly impossible to analyze. Scientists expect them to be an unexplored fount of data to test theoretical models about the solar system’s formation and how the planets ended up in their current orbits around the sun.
What other deep-space missions does NASA have coming up soon?
Two more asteroid missions will eventually follow Lucy, along with:
-
DART: Launching in November, NASA’s Double Asteroid Redirect Test (DART) mission involves crashing a spacecraft into an asteroid to nudge it off course. The mission tests out a method of planetary defense that could one day come in handy should an asteroid threaten Earth.
-
James Webb Space Telescope: A roughly $10 billion follow-up to NASA’s well-known Hubble telescope, the Webb is scheduled to, at last, launch in December. It will study planets orbiting distant stars and search for light from the first galaxies that formed after the Big Bang.
-
Artemis-1: NASA aims in the months ahead to launch an uncrewed Orion astronaut capsule atop its massive Space Launch System rocket around the moon and back. It’s the first mission under the agency’s Artemis program, which aims to one day send American astronauts back to the moon.
-
Psyche: Next year, NASA is scheduled to send a probe to Psyche, a metallic asteroid in the belt between Mars and Jupiter made of nickel and iron that resembles the core of an early planetary body. Like the asteroids of Lucy’s mission, it could provide clues to the formation of our solar system.
-
Europa Clipper: In 2024, NASA intends to send a spacecraft toward Jupiter to scan the icy moon Europa and determine whether its subsurface ocean could harbor life.
BEIJING, Oct. 19 (Xinhua) — Chinese researchers have studied the
lunar samples brought back by the Chang’e-5 mission and dated the
youngest rock on the Moon at around 2 billion years in age, extending
the “life” of lunar volcanism 800-900 million years longer than
previously known.
The study, conducted mainly by a research team at the Institute of
Geology and Geophysics (IGG), Chinese Academy of Sciences (CAS), was
presented in three Nature papers and published online Tuesday.
Last year, China’s Chang’e-5 mission retrieved samples from the Moon
weighing about 1,731 grams, which were the first lunar samples in the
world in over 40 years.
“The Chang’e-5 mission was a success and the lunar samples brought
back shed new light on the evolution of the Moon,” said Li Xianhua, an
academician with CAS who led the research team.
DATING MOON ROCKS
“The magma of the Moon has solidified, and the Moon’s geologic
activity has already ceased. When the Moon’s volcanic activity stopped,
it emerged as one of the major issues in its evolutionary history,” said
Li Qiuli, head of the secondary ion mass spectrometry laboratory of
IGG.
The youngest dated rock from the Apollo and Luna missions and lunar
meteorites was around 2.8-2.9 billion years old. However, more samples
are needed and one of the Chang’e-5 tasks is to explore the youngest
magmatic activity of the Moon.
“The dimply surface we see when we look up at the Moon through a
telescope is due to the fact that many asteroids have collided with it
over billions of years. Older rocky regions have experienced more impact
craters over time, and regions with younger rocks have fewer craters,”
said Li Qiuli.
Using the method of chronology known as crater counting, researchers
inferred that the Oceanus Procellarum, the landing site of the Chang’e-5
mission, was most likely to have been witness to one of the Moon’s last
volcanic eruptions. Researchers could then calibrate the results from
crater counting with radioisotopically dated samples.
Radioisotopic dating works on the principle that radioactive elements
have constant decay rates. By measuring the relative abundances of the
parent and daughter isotopes, researchers will know how long the decay
has been taking place.
Using the microscope, researchers manually picked out rock fragments
from their 3-gram lunar samples, which is as difficult as separating
black flour from white flour by hand. Most of these minerals suitable
for dating are only one-twentieth of the diameter of a hair.
Li Qiuli said that the research team had been well-prepared for
studying the lunar samples retrieved by China, and has continuously
developed the ion probe technology in the past decade, reaching an
internationally acclaimed level of expertise.
“Our palms were sweaty as we loaded the sample and turned on the mass
spectrometer. When we saw the age it spat out, we couldn’t believe our
luck. But we wanted to be sure,” said Li Qiuli, adding that they carried
out more than 200 tests.
In total, the team analyzed 47 different rock fragments extracted
from the sample materials and dated the youngest rock on the Moon at
2.03 billion years old. The new age extends the life of lunar volcanism
800-900 million years longer than previously known.
OUT OF EXPECTATION
“The Moon is only around one percent the mass of Earth. At that
strikingly small size, theoretically, at least, it should have
completely solidified at a quick pace. Our team investigated further why
volcanic activity still existed on the Moon so late,” said Li Xianhua.
Lunar scientists focused on KREEP, an acronym built from the letters K
(for potassium), REE (for rare-earth elements) and P (for phosphorus),
which is a distinctive geochemical component of some lunar rocks.
“A widely accepted hypothesis is that radioactive elements (U, Th and
K) supplied the heat necessary for the late volcanic activity. Because
KREEP is rich in radiogenic elements U, Th and K, it is therefore
thought to be responsible for the young volcanic activity,” said Yang
Wei, a researcher with IGG.
“Isotopes are an effective way to identify the KREEP component as
they are like the DNA of a rock and will not change through the magmatic
evolution,” said Yang.
However, the difficulty lies in the small size of the basalt clasts
in the Chang’e-5 lunar samples. It is hard to obtain the isotope ratios
of the Chang’e-5 basalt.
“It’s like DNA testing, which requires a large tube of blood, but we can only use one drop,” said Yang.
Thanks to the institute’s efforts over a decade, a state-of-the-art
method for analyzing samples under high magnification has been
developed, allowing researchers to obtain the strontium and neodymium
isotope ratios of specific minerals.
The results were beyond expectations. The Chang’e-5 basalt, the
youngest basalt dated on the Moon so far, originated from a depleted
mantle source with a KREEP component measuring less than 0.5 percent of
its weight.
In other words, it is unlikely that the KREEP components in the lunar
mantle supplied the heat necessary for the late volcanic activity.
WATER CONTENT
Another possible cause of volcanic activity on the Moon at such a
late age is that the mantle source might have contained water to reduce
its melting point, said scientists.
“The water content of the lunar mantle is a key question for lunar
exploration because it provides critical constraints on the formation of
the Moon. Furthermore, since water can significantly decrease the
melting temperature of rocks, understanding its abundance is important
for understanding the history of lunar volcanism,” said Lin Yangting, a
researcher with IGG.
The large discrepancy in water abundance estimates of the lunar
mantle could be mainly attributed to the Apollo samples and lunar
meteorites being generally quite old.
Most previous lunar samples with measured water content date back to 3
billion years or earlier. Such old rocks could have undergone heavy
modifications over a long time by the impact of asteroids and particles
from the sun.
“The samples retrieved by Chang’e-5 were from a single basaltic lava
flow. With such a simple and clear geological setting, the samples,
therefore, provide a good opportunity to address the question of whether
the mantle reservoir at 2 billion years was wet or dry,” said Lin.
The research team analyzed the water contents and hydrogen isotopes
of pockets of melt preserved in some minerals as well as the mineral
apatite, which can contain water, from Chang’e-5 basalts.
“We used a nano-scale ion probe called the nanoSIMS, a secondary ion
mass spectrometer with an ion beam down to 50 nanometers in diameter.
The relative abundances of the two isotopes of hydrogen (deuterium [D]
and hydrogen [H]) can serve as a ‘fingerprint’ to trace the reservoirs
of water and the magmatic processes involved,” said Lin.
The results indicated that the mantle source of the Chang’e-5 basalts
was drier than the estimated water content based on the Apollo samples
and lunar meteorites, which rules out the possibility that high water
content in the mantle source was the cause of the usually young volcanic
eruption.
The mystery of the late lunar volcanic activity is yet to be solved.
“Our discoveries raise new questions for the future of lunar
exploration and scientists need to further explore the formation
mechanism of the lunar magma,” said Li Xianhua.
The latest mission of the American space agency, NASA, will explore a group of ancient objects orbiting the sun at the distance of Jupiter.
Set to launch October 16, the Lucy spacecraft is designed to study Jupiter’s “Trojan” asteroids.
These asteroids are small bodies left over from the formation of our solar system’s large planets. They share an orbit with Jupiter as the planet goes around the sun.
The mission’s aim is to gather new information about the solar system’s formation 4.5 billion years ago.
Lucy will observe eight asteroids over 12 years. One orbits in what is known as the Asteroid Belt, an area between Mars and Jupiter. Most known asteroids orbit within this area.
The spacecraft will also observe seven Trojan asteroids. The Trojans circle the sun in two groups. One group leads Jupiter in its orbital path, while the other follows behind it. Lucy will be the first spacecraft to visit these asteroids. There are believed to be more than 7,000 Trojan asteroids.
Scientists consider the Trojan asteroids to be the ancient remains of the formation of the solar system. They have stayed captured in Jupiter’s orbit for billions of years. Scientists hope that the NASA mission can provide new details about what conditions were like when the planets formed. They also hope the mission will lead to a better understanding of our own planet’s history.
The spacecraft was named Lucy after the ancient fossil discovered in Ethiopia in 1974. Lucy was one of the most famous scientific finds of the 20th century. The collection of skeletal bones gave scientists a better understanding of the evolution of humans.
Cathy Olkin is a planetary scientist at the Southwest Research Institute in Colorado. She is the deputy lead investigator for the Lucy mission. In a video explaining the mission, Olkin compared the NASA spacecraft to the Lucy fossil.
“Just like the Lucy fossil transformed our understanding of (human) evolution, the Lucy mission will transform our understanding of solar system evolution,” she said.
The spacecraft, built by NASA contractor Lockheed Martin, is expected to fly within 400 kilometers of its targets.
The spacecraft is equipped with several imaging instruments designed to capture information about the composition of materials on the surface of asteroids. Other equipment will be used to record asteroid surface temperatures and measure the size of the objects the spacecraft observes.
Lucy will depend on solar power to operate. NASA says the mission expects to set a record because Lucy will be deployed farther from the sun than any past solar powered spacecraft.
Hal Levison is the mission’s chief scientist. He recently told reporters that although the Trojan asteroids are in a very small area of space, they are physically different from each another.
“For example, they have very different colors, some are grey, some are red,” Levison said. He added that these differences suggest how far away from the Sun they might have formed before getting to their current positions.
Lori Glaze is the director of NASA’s planetary science division. She said: “Whatever Lucy finds will give us vital clues about the formation of our solar system.”
I’m Bryan Lynn.
Bryan Lynn wrote this story based on reports from NASA, Agence France-Presse and Lockheed Martin. Mario Ritter, Jr. was the editor.
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Words in This Story
mission – n. an important project or trip, especially involving space travel
asteroid – n. one of many large rocks that circle the sun
fossil – n. part of an animal or plant from thousands of year ago, preserved as minerals in rock
evolution – n. a gradual process of change and development
transform – v. to change something completely, usually to improve it
composition – n. the parts, substances, etc. that something is made up of
vital – adj. necessary or important
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