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Australian fish fossils get to the heart of vertebrate evolution

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By: Reuters, Updated: September 18, 2022

Scientists in Australia have unearthed beautifully preserved fossilized hearts and other internal organs of ancient armored fish in a discovery that provides insight into the evolution of the bodies of vertebrates – including humans.

The researchers on Thursday described the heart, the organ that pumps blood through the body’s circulatory system, in fish called placoderms that inhabited a tropical reef about 380 million years ago during the Devonian Period. The fossils were 250 million years older than any previously known fish heart.

The fossilized liver, stomach and intestine from these placoderms helped give a fuller view of the internal anatomy at a pivotal time in the history of vertebrates – backboned animals including fish, amphibians, reptiles, birds and mammals.

The fossils were found in a locale called the Gogo Formation in Western Australia’s Kimberley region near the town of Fitzroy Crossing. They are remarkable because soft tissue, unlike hard stuff such as bones and teeth, is rarely preserved as fossils and even less often preserved in a robust three dimensions, as these are, rather than flattened.

“The site is without a doubt one of the world’s most important fossil sites for understanding the early evolution of backboned animals, including the origins of the human body plan,” said vertebrate paleontologist Kate Trinajstic of Curtin University and the Western Australian Museum, lead author of the study published in the journal Science. Placoderms, known for bony armor on the head and neck, represented “our earliest jawed ancestors,” Trinajstic said.

The newly described fossils are of two species, named Compagopiscis croucheri and Incisoscutum ritchiei, both about 10 inches (25 cm) long with shark-like asymmetrical tail fins, jaws bearing teeth and blade-like cutting edges, and broad, blunt-nosed heads.

The placoderms had an S-shaped heart similar to that of a shark. It was made up of two chambers, with a smaller one on top and a larger one underneath, and was located at the front of the shoulder girdle in a similar position to sharks and bony fish today. Its structure differs from later vertebrates. Amphibians and reptiles have a three-chambered heart, while mammals and birds have a four-chambered heart.

In land vertebrates, which evolved from fish during the Devonian, the heart has moved further back along the body – or down from the perspective of upright humans. If a person’s heart was in the same place as these placoderms, it would be at the base of the throat between the collar bones.

The placoderm liver was large and enabled the fish to remain buoyant, as in sharks. The liver showed how placoderms had evolved away from the organ arrangement of jawless fish. In jawless fish called lampreys, the liver is squashed against the heart and envelops it from behind. The placoderms displayed a heart-liver separation like modern jawed vertebrates.

The placoderm stomach, shaped like a flattened and somewhat rectangular bag, has a distinctive wall texture, thick and honeycombed, apparently representing glandular tissue. The intestine has spiral valves to help with food absorption. There was no evidence of lungs.

The single biggest step in the evolution of vertebrates was the transition from the ancestral jawless condition, reflected in modern lampreys and hagfish, to the jawed vertebrate body plan, said paleontologist and study co-author Per Ahlberg of the University of Uppsala in Sweden.

“Today, the overwhelming majority of vertebrates belong to the jawed group: sharks, rays, bony fishes and all land vertebrates including humans. This transition didn’t just involve the evolution of jaws, but also all kinds of changes in the soft anatomy – for example the evolution of a stomach, and the heart moving forward into the throat region,” Ahlberg said.

“But while fossils give us a reasonably complete picture of the evolution of the skeleton, the equally important soft organs usually don’t fossilize at all, which means that we are left guessing about the details of their evolutionary transformation,” Ahlberg added.

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SpaceX Rocket With Next International Space Station Crew Enters Orbit, Including Russian Cosmonaut: All Details

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A SpaceX Falcon 9, with NASA astronauts Doug Hurley and Bob Behnken in the Dragon crew capsule, lifts off from Pad 39A at the Kennedy Space Center in Cape Canaveral, Fla., on Saturday. David J. Phillip/AP
By Reuters | Updated: 6 October 2022

A SpaceX rocket soared into orbit from Florida on Wednesday carrying the next long-term International Space Station crew, with a Russian cosmonaut, two Americans and a Japanese astronaut flying together in a demonstration of US-Russian teamwork in space despite Ukraine war tensions.

A high-ranking official of the Russian space agency Roscosmos said shortly after the launch that the flight marked “a new phase of our cooperation” with the US space agency NASA.

The SpaceX launch vehicle, consisting of a Falcon 9 rocket topped with a Crew Dragon capsule dubbed Endurance, lifted off into clear skies at noon EDT (9:30pm IST) from NASA’s Kennedy Space Center in Cape Canaveral. The two-stage, 23-story-tall Falcon 9 ascended from the launch tower as its nine Merlin engines roared to life in billowing clouds of vapor and a reddish-orange fireball.

The mission is notable for the inclusion of Anna Kikina, 38, the lone female cosmonaut on active duty with Roscosmos, making it the first spaceflight with a Russian launched from US soil in two decades. As the spacecraft entered Earth orbit, Kikina radioed her thanks to NASA, Roscosmos and their International Space Station (ISS) partners for “giving us this great opportunity.”

“We’re so glad to do it together,” Kikina said.

Kikina, who had trained in the US for the flight since spring 2021, was essentially swapping places with a NASA astronaut who took her seat aboard a Russian Soyuz flight to the ISS last month under a new ride-sharing deal signed by NASA and Roscosmos in July.

About nine minutes after Wednesday’s launch, the rocket’s upper stage delivered the Crew Dragon into a preliminary orbit as it streaked through space at nearly 16,000 miles per hour (27,000 kph). The reusable lower-stage booster flew itself back to Earth and landed safely on a drone recovery vessel at sea.

The four crew members and their autonomously flying capsule were due to reach the ISS in about 29 hours, on Thursday evening, to begin a 150-day science mission aboard the orbital laboratory some 250 miles (420 km) above Earth.

The mission, designated Crew-5, marks the fifth full-fledged ISS crew NASA has flown aboard a SpaceX vehicle since the private rocket venture founded by Tesla CEO Elon Musk began sending US astronauts aloft in May 2020.
‘Smooth ride’

The team was led by Nicole Aunapu Mann, 45, who became the first Native American woman sent to orbit by NASA and the first woman to take the commander’s seat of a SpaceX Crew Dragon.

Moments after reaching orbit, as mission control wished the crew “Godspeed,” Mann radioed back, “Awesome. Thank you so much to the Falcon team. Whew! That was a smooth ride uphill.”

Mann, a U.S. Marine Corps colonel and combat fighter pilot, is also among the first group of 18 astronauts selected for NASA’s upcoming Artemis missions aimed at returning humans to the moon later this decade.

The designated pilot was Mann’s fellow spaceflight rookie Josh Cassada, 49, a U.S. Navy aviator and test pilot with a doctorate in high-energy particle physics. Rounding out the crew from Japan’s space agency JAXA was Koichi Wakata, 59, a robotics expert making his fifth voyage to space.

The team will be welcomed by seven existing ISS occupants – the Crew-4 team consisting of three Americans and an Italian astronaut – as well as two Russians and the NASA astronaut who flew with them to orbit on a Soyuz flight.

The new arrivals are set to conduct more than 200 experiments, many focused on medical research ranging from 3-D “bio-printing” of human tissue to a study of bacteria cultured in microgravity.

ISS, the length of a football field, has been continuously occupied since 2000, operated by a US-Russian-led consortium that includes Canada, Japan and 11 European countries. It was born in part to improve relations between Washington and Moscow following the Soviet Union’s collapse and the end of Cold War rivalries that spurred the original American-Soviet space race.

NASA-Roscosmos relations have been tested since Russia invaded Ukraine in February and US imposed sweeping sanctions against Moscow.

At a post-launch NASA-SpaceX briefing on Wednesday, Sergei Krikalev, head of human spaceflight for Roscosmos, said he and the agency chief Yuri Borisov were seeking to ease tensions after Borisov’s predecessor, Dmitry Rogozin, raised questions about the future of the ISS partnership.

Krikalev cited bilateral teamwork in space dating back to the Apollo-Soyuz era in 1975, saying, “We started our cooperation many years ago, over 40 years ago, and will continue our cooperation as long as I can imagine.”

The July crew-exchange deal paved the way for resuming routine joint US-Russian flights to the ISS that had begun during the space shuttle era and continued after shuttles ceased flying in 2011. From then until SpaceX began offering crewed launch services nine years later, Soyuz was the only avenue to orbit for US astronauts.

© Thomson Reuters 2022

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SpaceX to Fly Russian Cosmonaut Anna Kikina to International Space Station Amid Ukraine War

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By Agence France-Presse | Updated: 5 October 2022

The United States will on Wednesday carry a Russian to the International Space Station aboard a SpaceX ship, in a voyage that carries symbolic significance amid the Ukraine war.

Anna Kikina, the only female cosmonaut in service, is part of the Crew-5 mission, which also includes one Japanese and two American astronauts.

Blast-off is set for noon from the Kennedy Space Center, with the weather forecast so far promising.

Two weeks ago, an American astronaut took off on a Russian Soyuz rocket for the orbital platform.

The long-planned astronaut exchange program has been maintained despite soaring tensions between the two countries since Moscow’s invasion of Ukraine in February.

Ensuring the operation of the ISS has become one of the few remaining areas of cooperation between the United States and Russia.

“When you each are flying other’s crew members, you know that you have a huge responsibility that you’re promising to the other country,” NASA associate administrator Kathy Lueders told reporters in a recent press conference.

“At a working level, we really appreciated the constancy in the relationship, even during some really, really tough times geopolitically.”

Fifth female cosmonaut

Kikina, 38 and an engineer by training, will become the fifth Russian female professional cosmonaut to go into space.

“I hope in the near future we have more women in the cosmonaut corps,” the Novosibirsk native told AFP in August.

The Soviet Union put the first woman in space, Valentina Tereshkova, in 1963, nearly 20 years before the first American woman Sally Ride. Since then, America has flown dozens more women.

It will also be the first spaceflight for American astronauts Nicole Mann and Josh Cassada, but the fifth for Japan’s Koichi Wakata.

After a journey of about 30 hours, their ship will dock with the station on Thursday, ready to begin a five-month science mission and relieve the four members of Crew-4, who will stay a few days for handover.

Crew-5’s arrival will bring the total number of astronauts on the ISS to 11, including two other Russians and an American who arrived on the recent Soyuz.

ISS future unclear

Kikina will be the first Russian to fly with Elon Musk’s SpaceX which, along with Boeing, has a “taxi service” contract with NASA.

Musk himself waded into the conflict Thursday by proposing a peace deal that involved re-running, under UN supervision, annexation referendums in Moscow-occupied regions of Ukraine and acknowledging Russian sovereignty over the Crimean peninsula.

The post enraged Ukrainians, including the country’s envoy to Germany, who responded with an expletive.

Tensions between Moscow and Washington have increased considerably in the space field after the announcement of American sanctions against the Russian aerospace industry, in response to the invasion of Ukraine.

Russia thus announced this summer that it wanted to leave the ISS “after 2024” in favor of creating its own station, albeit without setting a precise date.

The director of manned flights at Roscosmos, Sergei Krikaliov, declared Monday he hoped the Russian government agrees to extend participation in the ISS after 2024.

The United States, for its part, wants to continue operating until at least 2030, then transition to commercially run stations.

As things stand, the ISS cannot function without joint cooperation, as the US side is responsible for power and life support and the Russian side for propulsion and maintaining orbit.

Between 2011 — when the Space Shuttle program ended — and SpaceX’s first flight to the ISS in 2020, the United States was dependent on Russia for flying its crew to the station, paying tens of millions of dollars per seat.

The loss of this monopoly represents a significant income reduction for the Russian space program. The current crew exchange program, by contrast, is a barter-based agreement with no exchange of money.

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NASA, SpaceX to Explore Methods to Boost Hubble Telescope Orbit to Extend Lifespan

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By Agence France-Presse | Updated: 30 September 2022

NASA and SpaceX have agreed to study the feasibility of awarding Elon Musk’s company a contract to boost the Hubble Space Telescope to a higher orbit, with a goal of extending its lifespan, the US space agency said Thursday.

The renowned observatory has been operating since 1990 about 335 miles (540 kilometers) above Earth, in an orbit that slowly decays over time.

Hubble has no on-board propulsion to counter the small but still present atmospheric drag in this region of space, and its altitude has previously been restored during Space Shuttle missions.

The proposed new effort would involve a SpaceX Dragon capsule.

“A few months ago, SpaceX approached NASA with the idea for a study whether a commercial crew could help reboost our Hubble spacecraft,” NASA’s chief scientist Thomas Zurbuchen told reporters, adding the agency had agreed to the study at no cost to itself.

He stressed there are no concrete plans at present to conduct or fund such a mission until the technical challenges are better understood.

One of the main obstacles would be that the Dragon spacecraft, unlike the Space Shuttles, does not have a robotic arm and would need modifications for such a mission.

SpaceX proposed the idea in partnership with the Polaris programme, a private human spaceflight venture led by payments billionaire Jared Isaacman, who last year chartered a SpaceX Crew Dragon to orbit the Earth with three other private astronauts.

“This would certainly fit within the parameters we established for the Polaris programme,” Isaacman said in response to a question about whether reboosting Hubble could be the goal for a future Polaris mission.

Asked by a reporter whether there might be a perception that the mission was contrived in order to give wealthy people tasks to do in space, Zurbuchen said: “I think it’s only appropriate for us to look at this because of the tremendous value this research as

set has for us.”

Arguably among the most valuable instruments in scientific history, Hubble continues to make important discoveries, including this year detecting the farthest individual star ever seen — Earendel, whose light took 12.9 billion years to reach us.

It is currently forecast to remain operational throughout this decade, with a 50 percent chance of de-orbiting in 2037, said Patrick Crouse, Hubble Space Telescope project manager.

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Cosmicflows-4: Astronomers Assemble Largest Catalogue of 56,000 Galaxy Distances

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By ANI | Updated: 29 September 2022

Astronomers have assembled the largest-ever compilation of high-precision galaxy distances, called Cosmicflows-4. Galaxies, such as the Milky Way, are the building blocks of the universe, each comprised of up to several hundred billion stars. Galaxies beyond our immediate neighborhood are rushing away, faster if they are more distant, which is a consequence of the expansion of the universe that began at the moment of the Big Bang. Measurements of the distances of galaxies, coupled with information about their velocities away from us, determine the scale of the universe and the time that has elapsed since its birth.

“Since galaxies were identified as separate from the Milky Way a hundred years ago, astronomers have been trying to measure their distances,” said Brent Tully, astronomer at the University of Hawaii at Manoa. “Now by combining our more accurate and abundant tools, we are able to measure distances of galaxies, and the related expansion rate of the universe and the time since the universe was born with a precision of a few per cent.”

From the newly published measurements, the researchers derived the expansion rate of the universe, called the Hubble Constant, or H0. The team’s study gives a value of H0=75 kilometers per second per megaparsec or Mpc (1 megaparsec = 3.26 million light years), with very small statistical uncertainty of about 1.5 percent.

Astronomers have assembled the largest-ever compilation of high-precision galaxy distances, called Cosmicflows-4. Galaxies, such as the Milky Way, are the building blocks of the universe, each comprised of up to several hundred billion stars. Galaxies beyond our immediate neighborhood are rushing away, faster if they are more distant, which is a consequence of the expansion of the universe that began at the moment of the Big Bang. Measurements of the distances of galaxies, coupled with information about their velocities away from us, determine the scale of the universe and the time that has elapsed since its birth.

“Since galaxies were identified as separate from the Milky Way a hundred years ago, astronomers have been trying to measure their distances,” said Brent Tully, astronomer at the University of Hawaii at Manoa. “Now by combining our more accurate and abundant tools, we are able to measure distances of galaxies, and the related expansion rate of the universe and the time since the universe was born with a precision of a few per cent.”

From the newly published measurements, the researchers derived the expansion rate of the universe, called the Hubble Constant, or H0. The team’s study gives a value of H0=75 kilometers per second per megaparsec or Mpc (1 megaparsec = 3.26 million light years), with very small statistical uncertainty of about 1.5 percent.

Cosmicflows-4 is also being used to study how galaxies move individually, in addition to flowing with the overall expansion of the universe. Deviations from this smooth expansion arise due to the gravitational influences of clumps of matter, on scales ranging from our Earth and Sun up to congregations of galaxies on scales of a half billion light years. The mysterious dark matter is the dominant component on larger scales. With knowledge of the motions of galaxies in response to the mass around them, we can recreate the orbits that galaxies have followed since they were formed, giving us a better understanding of how the universe’s vast, dark-matter-dominated structures have formed over the eons of time.

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NASA DART Spacecraft Successfully Slams Into Asteroid Dimorphos in First Planetary Defence Test

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By Reuters | Updated: 27 September 2022

NASA’s DART spacecraft successfully slammed into a distant asteroid at hypersonic speed on Monday in the world’s first test of a planetary defense system, designed to prevent a potential doomsday meteorite collision with Earth.

Humanity’s first attempt to alter the motion of an asteroid or any celestial body played out in a NASA webcast from the mission operations center outside Washington, DC, 10 months after DART was launched.

The livestream showed images taken by DART’s camera as the cube-shaped “impactor” vehicle, no bigger than a vending machine with two rectangular solar arrays, streaked into the asteroid Dimorphos, about the size of a football stadium, at 7:14 pm EDT (23:14 GMT) some 6.8 million miles (11 million km) from Earth.

The $330 million (roughly Rs. 2,683 crore) mission, some seven years in development, was devised to determine if a spacecraft is capable of changing the trajectory of an asteroid through sheer kinetic force, nudging it off course just enough to keep Earth out of harm’s way.

Whether the experiment succeeded beyond accomplishing its intended impact will not be known until further ground-based telescope observations of the asteroid next month. But NASA officials hailed the immediate outcome of Monday’s test, saying the spacecraft achieved its purpose.

“NASA works for the benefit of humanity, so for us it’s the ultimate fulfillment of our mission to do something like this – a technology demonstration that, who knows, some day could save our home,” NASA Deputy Administrator Pam Melroy, a retired astronaut, said minutes after the impact.

DART, launched by a SpaceX rocket in November 2021, made most of its voyage under the guidance of NASA’s flight directors, with control handed over to an autonomous on-board navigation system in the final hours of the journey.

Monday evening’s bullseye impact was monitored in near real time from the mission operations center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

Cheers erupted from the control room as second-by-second images of the target asteroid, captured by DART’s onboard camera, grew larger and ultimately filled the TV screen of NASA’s live webcast just before the signal was lost, confirming the spacecraft had crashed into Dimorphos.

DART’s celestial target was an oblong asteroid “moonlet” about 560 feet (170 meters) in diameter that orbits a parent asteroid five times larger called Didymos as part of a binary pair with the same name, the Greek word for twin.

Neither object presents any actual threat to Earth, and NASA scientists said their DART test could not create a new hazard by mistake.

Dimorphos and Didymos are both tiny compared with the cataclysmic Chicxulub asteroid that struck Earth some 66 million years ago, wiping out about three-quarters of the world’s plant and animal species including the dinosaurs.

Smaller asteroids are far more common and present a greater theoretical concern in the near term, making the Didymos pair suitable test subjects for their size, according to NASA scientists and planetary defense experts. A Dimorphos-sized asteroid, while not capable of posing a planet-wide threat, could level a major city with a direct hit.

Also, the two asteroids’ relative proximity to Earth and dual configuration make them ideal for the first proof-of-concept mission of DART, short for Double Asteroid Redirection Test.

Robotic suicide mission

The mission represented a rare instance in which a NASA spacecraft had to crash to succeed. DART flew directly into Dimorphos at 15,000 miles per hour (24,000 kph), creating the force scientists hope will be enough to shift its orbital track closer to the parent asteroid.

APL engineers said the spacecraft was presumably smashed to bits and left a small impact crater in the boulder-strewn surface of the asteroid.

The DART team said it expects to shorten the orbital path of Dimorphos by 10 minutes but would consider at least 73 seconds a success, proving the exercise as a viable technique to deflect an asteroid on a collision course with Earth – if one were ever discovered.

A nudge to an asteroid millions of miles away years in advance could be sufficient to safely reroute it.

Earlier calculations of the starting location and orbital period of Dimorphos were made during a six-day observation period in July and will be compared with post-impact measurements made in October to determine whether the asteroid budged and by how much.

Monday’s test also was observed by a camera mounted on a briefcase-sized mini-spacecraft released from DART days in advance, as well as by ground-based observatories and the Hubble and Webb space telescopes, but images from those were not immediately available.

DART is the latest of several NASA missions in recent years to explore and interact with asteroids, primordial rocky remnants from the solar system’s formation more than 4.5 billion years ago.

Last year, NASA launched a probe on a voyage to the Trojan asteroid clusters orbiting near Jupiter, while the grab-and-go spacecraft OSIRIS-REx is on its way back to Earth with a sample collected in October 2020 from the asteroid Bennu.

The Dimorphos moonlet is one of the smallest astronomical objects to receive a permanent name and is one of 27,500 known near-Earth asteroids of all sizes tracked by NASA. Although none are known to pose a foreseeable hazard to humankind, NASA estimates that many more asteroids remain undetected in the near-Earth vicinity.

© Thomson Reuters 2022

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ISRO Mars Orbiter Mission Completes Eight Years in Orbit, Well Beyond Planned Six-Month Lifespan

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By Press Trust of India | Updated: 26 September 2022

India’s Mars orbiter craft has completed eight years in its orbit, well beyond its designed mission life of six months. Plans on a follow-on ‘Mangalyaan’ mission to the Red Planet, however, are yet to be firmed up.

The Mars Orbiter Mission (MOM) – a technology demonstration venture – is the maiden interplanetary mission of the national space agency, the Indian Space Research Organisation (ISRO).

Launched on November 5, 2013, the probe was successfully inserted into Martian orbit on September 24, 2014 in its first attempt.

To mark the latest milestone, ISRO has organised a ‘National Meet on Eight Years of India’s Mars Orbiter Mission (MOM)’ at its headquarters here on Tuesday with an inaugural address by its Chairman S Somanath.

Space Commission members K Radhakrishnan and A S Kiran Kumar would deliver special addresses at the meet, which would focus on themes ‘Mars Orbiter Mission Overview’, ‘Scientific Achievements’ and ‘Future Directions in the exploration of the inner solar system’.

As the then chairman of ISRO, Radhakrishnan had led the MOM (Mangalyaan) mission team.

ISRO came out with an ‘Announcement of Opportunity’ (AO) for future Mars Orbiter Mission (MOM-2) in 2016 but officials acknowledged that it’s still on the drawing board, with the coming ‘Gaganyaan’, ‘Chandrayaan-3’ and ‘Aditya – L1’ projects being in the space agency’s current priority list.

The AO had said: “It is now planned to have the next orbiter mission around Mars for a future launch opportunity. Proposals are solicited from interested scientists within India for experiments onboard an orbiter mission around Mars (MOM-2), to address relevant scientific problems and topics”.

“Not in the approved list as of now”, a senior ISRO official told PTI on Monday on being asked about an update on the MOM-2.

“We need to formulate the project proposals and payloads based on the wider consultation with the research community”, the official said on condition of anonymity. “It’s still on the drawing board. But needs some more details and international collaboration for finalising the mission”.

“It’s quite a satisfying and fulfilling moment”, MOM’s Programme Director M Annadurai told PTI today on the Mars orbiter craft completing eight years in orbit.

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