Agency

03/05/2024
287 views
12 likes

ESA is committed to almost halve its greenhouse gas emissions linked to energy consumption by 2025 compared to 2019 levels. But how can ESA keep accelerating the use of space for the sustainable development of society while reducing its emissions?

With eight establishments across Europe, a spaceport in French Guiana and tracking stations all over the world, ESA has plenty of opportunities. Here are some of its big achievements in greenhouse gas reduction:

A better gas boiler

The European Space Research and Technology Centre (ESTEC) in the Netherlands replaced its old gas-fired boiler, which was responsible for about 75% of the site’s yearly gas consumption, with a state-of-the-art condensing gas boiler. The new system, in use since June 2021, can operate at a lower temperature while producing the heat required for older buildings. It is estimated to save 454,000 cubic meters of gas a year, or almost a 1000 tonnes of CO₂ equivalent. 

Heat pump upgrades

A high-efficiency heat pump that has been running at ESTEC since May 2023 saves around 450 000 cubic meters of gas per year, which equates to 990 tonnes of CO₂ equivalent. The system, which generates cold water while repurposing the extracted heat into a central heating network, reduced ESTEC’s annual gas consumption by 25%. In Spain, the new heat pump at the European Space Astronomy Centre (ESCAC) is the most innovative project in terms of energy efficiency. It has reduced diesel consumption by 95% and offers annual savings of about 295 tonnes of CO₂ equivalent. 

Embracing Earth energy

The European Space Operations Centre (ESOC) in Germany and the European Centre for Space Applications and Telecommunications (ECSAT) in the United Kingdom both have ground source heat pumps. These efficiently heat and cool the buildings they serve and have eliminated the use of gas for heating.

Data centre heat

The ESA Centre for Earth Observation (ESRIN) in Italy recovers energy generated by its data centre and uses it to heat offices. The project, which has been going since 2013, saves an estimated 55 tonnes of CO₂ equivalent a year.

Powered by the Sun

The photovoltaic panels at four major ESA sites – ESRIN, ESTEC, ECSAT and ESAC – save more than 500 tonnes of CO₂ equivalent a year. ESA’s deep-space ground station at New Norcia, Western Australia, is also powered in part by sunlight, thanks to a new solar power ‘farm’ of photovoltaic panels that covers about a third of the station’s electricity use. 

Making buildings better

The ESA headquarters in Paris, known as HQ Nikis, was recently refurbished with modern materials that reduce its environmental footprint. In its first year of operations, the refurbished HQ Nikis consumed 50% less electricity and heating energy than its previous version did in 2013.

LED lighting

All street lighting and main corridor lighting at ESTEC has been replaced with LEDs. More areas will be converted but, so far, the change saves about 95 tonnes of CO₂ equivalent a year.

Like

Thank you for liking

You have already liked this page, you can only like it once!

Thanks to next-generation satellite systems scientists have in place, like the National Oceanic and Atmospheric Administration’s GOES-R series, scientists are able to get high-definition images of Earth faster than ever before. This is data that helps paint a full picture of our planet; the satellites can be thought of as in collaboration with one another, using special tools to make measurements and take observations that would otherwise be nearly impossible to perform from the ground directly. Yet, as our climate continues to change at a rapid rate due to human activities like burning coal, and as scientists make more discoveries about how planet Earth itself works, technology needs to be updated. Only then can we truly understand what’s happening across our planet, including in terms of  weather systems that impact the land and dynamics occurring deep below the ocean’s surface.

Earlier this month, the NOAA shared in a release that scientists determined, for a second time within the last decade, that a global coral bleaching event is underway across the Atlantic, Pacific and Indian Ocean basins. Sea-surface temperature data, gleaned from a blend of NOAA and partner satellites, helped confirm the ongoing event. But while NOAA scientists continue analyzing and documenting the severity and extent of this global event, which is being driven by ocean warming and extreme marine heat stress, there’s still more to understand when it comes to the anatomy and ecology of our oceans.

Recent papers by Michael Brown and Konstantin Batygin, both astronomers at Caltech, are providing a whole new line of evidence in support of the existence of our solar system’s hypothesized Planet Nine.

First evidence

This distant, massive world was first predicted in 2014 by astronomers who noted the unusual orbits of various outer solar system bodies called extreme trans-Neptunian objects. Trans-Neptunian objects (TNOs) have orbits that are farther from the Sun than Neptune. Extreme TNOs, or ETNOs, have even more elongated, distant orbits that are unaffected by interactions with any of the known planets. The dwarf planet Sedna, discovered in late 2003, was the first known ETNO.

Following Sedna’s discovery was speculation that its odd orbit must imply the existence — and influence of — of some large unknown planet or perhaps a nearby passing star. Then, the discovery of the second ETNO in 2014 strongly pointed the finger toward an unknown planet as the likelier explanation, as described by astronomers Chad Trujillo and Scott Sheppard in a Nature paper. Meanwhile, other astronomers suggested that two large planets in orbital resonance with one another would be necessary to explain the similarities of the orbits of these extreme objects, which are now classified as Sednoids.

In 2016, Batygin and Brown first outlined in detail how the orbits of six of these objects could be explained by a specific Planet Nine. They predicted this world must have a mass at least 10 times that of Earth, and an orbit some 400 to 800 times the distance between Earth to the Sun. That’s some 13 to 26 times farther out than the orbit of Neptune, the outermost planet.

Now, Brown says, they’ve studied the orbits of 13 large ETNOs. And the clustering of some elements of their orbits “opened our eyes and made us say, ‘what the heck is going on?’” Brown tells Astronomy.

Natural consequences

What’s going on, he explains, is that they’re seeing “not just clustering in the direction the orbits point, but also they are all tilted off the plane of the ecliptic [the plane of the solar system] by an average of about 15°. So both of these things together are pretty strange.”

The researchers have seen similar clustering turned in the perihelia — the point of their closest approach to the Sun — of these distant objects that varies up and down, sometimes dipping close to Neptune’s orbit, and sometimes swinging farther away. “That turns out to be another natural consequence of Planet Nine,” Brown says. “We didn’t think about it at the time when we first proposed the planet, it was not in our minds. But we quickly realized that was it.”

Then, a third unexpected line of evidence emerged: a “very strange population of objects that no one had been able to explain,” Brown says. They are objects whose orbits “are twisted by about 90° from the plane of the solar system and are on very eccentric orbits.” These unusual orbits, he says, are “nearly impossible to explain without the existence of Planet Nine.

Now, in the latest results accepted for publication in The Astronomical Journal Letters, yet another line of evidence has emerged. It turns out there is yet another population of objects much closer to the Sun, between the orbits of Jupiter and Neptune, whose orbits also extend beyond Neptune.

Brown says these are likely objects that were originally part of a very distant population “that get captured into closer orbits and stick around for a long time.” The team’s analysis showed a smooth, gradual decline in the population of objects with perihelia closer to the Sun that Neptune, rather than the sharp cutoff just inside Neptune’s orbit that would occur without the influence of Planet Nine’s gravitational pull. “I can’t think of any other explanation that could possibly give that result,” he says.

In a separate paper, Brown, Batygin, and Matthew Holman of the Center for Astrophysics | Harvard & Smithsonian describe their detailed search of the regions of the sky where Planet Nine is expected to lie, using the vast database of images from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) on Haleakala, Maui. This search, combined with previous searches using other databases and the team’s own observations, has now ruled out the planet’s presence from 78 percent of the predicted region.

New tools

But there is new hope. Next year, the Vera C. Rubin Observatory will come online in Chile, scanning the entire southern sky every four days with the largest camera ever built. The team’s analysis says there is a very high probability that if Planet Nine exists, the Rubin system should be able to find it within a year or two, proving its existence once and for all.

“What’s great about this,” says Thomas Levenson, a professor of science journalism at MIT and author of The Hunt for Vulcan (Random House, 2015), “is that since the initial proposal, they’ve increasingly refined that prediction. They’ve used further observations of additional groups of these objects to make the prediction more explicit, more precise, and thus more falsifiable.”

He adds that “this is the way science is supposed to work, and it very often doesn’t work this way.” And as a fan of astronomy, he says, “what’s exciting is they hold out the prospect that this is testable in an ordinary human lifespan… With the right observatory, we can see things that will help us confirm or deny, and that observatory is almost at hand, it’s just set to go, and that’s very exciting.”

“I think the chances are good,” Brown says. But a detection “relies on the observatory choosing to push further into the Northern Hemisphere than the nominal plan has it doing,” a chance that has yet to be decided. And it also depends on Planet Nine not being “on the extreme far ends of its possibilities” in terms of location and distance.

“It could be farther away than our initial predictions, and in that case, [the Rubin Observatory] will not be able to track it down either, and I’ll be depressed,” Brown says. But he adds that “if Planet Nine is not out there, we need a separate explanation for each of these other things, that can all be explained by a single Planet Nine. So it’s a very elegant solution to a lot of different problems, which is a good sign that it’s probably there.”

“Until there’s a better explanation for all these phenomena, I still think Planet Nine is probably real,” he says.

Does another undetected planet languish in our Solar System’s distant reaches? Does it follow a distant orbit around the Sun in the murky realm of comets and other icy objects? For some researchers, the answer is “almost certainly.”

The case for Planet Nine (P9) goes back at least as far as 2016. In that year, astronomers Mike Brown and Konstantin Batygin published evidence pointing to its existence. Along with colleagues, they’ve published other work supporting P9 since then.

There’s lots of evidence for the existence of P9, but none of it has reached the threshold of definitive proof. The main evidence concerns the orbits of Extreme Trans-Neptunian Objects (ETNOs). They exhibit a peculiar clustering that indicates a massive object. P9 might be shepherding these objects along on their orbits.

The names Brown and Batygin, both Caltech astronomers, come up often in regard to P9. Now, they’ve published another paper along with colleagues Alessandro Morbidelli and David Nesvorny, presenting more evidence supporting P9.

It’s titled “Generation of Low-Inclination, Neptune-Crossing TNOs by Planet Nine.” It’s published in The Astrophysical Journal Letters.

“The solar system’s distant reaches exhibit a wealth of anomalous dynamical structure, hinting at the presence of a yet-undetected, massive trans-Neptunian body—Planet Nine (P9),” the authors write. “Previous analyses have shown how orbital evolution induced by this object can explain the origins of a broad assortment of exotic orbits.”

To dig deeper into the issue, Batygin, Brown, Morbidelli, and Nesvorny examined Trans-Neptunian Objects (TNOs) with more conventional orbits. They carried out N-body simulations of these objects that included everything from the tug of giant planets and the Galactic Tide to passing stars.

29 objects in the Minor Planet Database have well-characterized orbits with a > 100 au, inclinations < 40°, and q (perihelia) < 30 au. Of those 29, 17 have well-quantified orbits. The researchers focused their simulations on these 17.

The researchers’ goal was to analyze these objects’ origins and determine if they could be used as a probe for P9. To accomplish this, they conducted two separate sets of simulations. One set with P9 in the Solar System and one set without.

The simulations began at t=300 million years, meaning 300 million years into the Solar System’s existence. At that time, “intrinsic dynamical evolution in the outer solar system is still in its infancy,” the authors explain, while enough time has passed for the Solar System’s birth cluster of stars to disperse and for the giant planets to have largely concluded their migrations. They ended up with about 2000 objects, or particles, in the simulation with perihelia greater than 30 au and semimajor axes between 100 and 5000 au. This ruled out all Neptune-crossing objects from the simulation’s starting conditions. “Importantly, this choice of initial conditions is inherently linked with the assumed orbit of P9,” they point out.

The figure below shows the evolution of some of the 2,000 objects in the simulations.

These are interesting results, but the researchers point out that they in no way prove the existence of P9. These orbits could be generated by other things like the Galactic Tide. In their next step, they examined their perihelion distribution.

“Accounting for observational biases, our results reveal that the orbital architecture of this group of objects aligns closely with the predictions of the P9-inclusive model,” the authors write. “In stark contrast, the P9-free scenario is statistically rejected at a ~5? confidence level.”

The authors point out that something other than P9 could be causing the orbital unruliness. The star was born in a cluster, and cluster dynamics could’ve set these objects on their unusual orbits before the cluster dispersed. A number of Earth-mass rogue planets could also be responsible, influencing the outer Solar System’s architecture for a few hundred million years before being removed somehow.

However, the authors chose their 17 TNOs for a reason. “Due to their low inclinations and perihelia, these objects experience rapid orbital chaos and have short dynamical lifetimes,” the authors write. That means that whatever is driving these objects into these orbits is ongoing and not a relic from the past.

An important result of this work is that it results in falsifiable predictions. And we may not have to wait long for the results to be tested. “Excitingly, the dynamics described here, along with all other lines of evidence for P9, will soon face a rigorous test with the operational commencement of the VRO (Vera Rubin Observatory),” the authors write.

If P9 is real, what is it? It could be the core of a giant planet ejected during the Solar System’s early days. It could be a rogue planet that drifted through interstellar space until being caught up in our Solar System’s gravitational milieu. Or it could be a planet that formed on a distant orbit, and a passing star shepherded it into its eccentric orbit. If astronomers can confirm P9’s existence, the next question will be, ‘what is it?’

If you’re interested at all in how science operates, the case of P9 is very instructive. Eureka moments are few and far between in modern astronomy. Evidence mounts incrementally, accompanied by discussion and counterpoint. Objections are raised and inconsistencies pointed out, then methods are refined and thinking advances. What began as one over-arching question is broken down into smaller, more easily-answered ones.

But the big question dominates for now and likely will for a while longer: Is there a Planet Nine?

Stay tuned.

Enabling & Support

06/05/2024
492 views
7 likes

Two bus-sized asteroids will zip past Earth closely but safely this week, starting with a 7-meter-long (22-feet) space rock named 2024 JF that’s expected to pass by on Monday (May 6) evening. 

Astronomers expect 2024 JF to make its closest approach at 8:04 p.m. ET tonight (1204 GMT on Tuesday). It will be followed by the 10-meter-long (32-feet) asteroid named 2024 JR1, which is expected to make its closest approach on Tuesday (May 7).

Back to Article List

Considering its distance, the uncertainty in its location, and the breadth of its orbital path, this hypothetical planet is exceedingly difficult to detect.

If the James Webb Space Telescope can see galaxies billions of light-years away, why can’t it find the proposed Planet X somewhere in our solar system beyond Pluto?

Terry Murray
Cincinnati, Ohio

Your excellent question demonstrates that at times celestial reality can defy terrestrial intuition.

One would think that astronomical objects within our solar system would be more readily observable than galaxies billions of light-years away. However, in astronomy, apparent brightness is more important than proximity. For instance, the Andromeda Galaxy (magnitude 3.4) appears approximately 12,000 times brighter in our sky than Pluto at its maximum brightness (magnitude 13.6) despite the former’s 2.5-million-light-year distance. All the same, one can observe Pluto with a sufficiently powerful telescope because its location is precisely known at any given time.

Finding Planet X, assuming it exists, is far more complicated. In January 2016, Caltech astronomers Konstantin Batygin and Mike Brown published a paper in The Astronomical Journal in which they cited evidence for a giant planet that might be five to 10 times more massive than Earth, with an average distance between 400 and 800 AU from the Sun. Pluto’s average heliocentric distance is 39 AU. Even if Planet X is truly a giant and reflects a lot of light, it will appear quite faint because the intensity of light diminishes with the square of the distance. At the minimum 400-AU distance, the Sun will appear at least 100 times fainter than it does at 39 AU. Any reflected light from Planet X will appear even fainter after traversing the solar system a second time to reach Earth.

Considering its distance, the uncertainty in its location, and the breadth of its orbital path, this planet would be exceedingly difficult to detect in conventional sky searches. And astronomers will not only have to detect Planet X, but also distinguish it from background stars by virtue of the motion it exhibits relative to them. Recall that Clyde Tombaugh (1906–1997) detected Pluto after a year of meticulous searching with a blink comparator, a machine that compares two different images of the sky to look for differences. The search field for Planet X is broader and, owing to its greater distance and commensurately slower orbital motion, its changes in position relative to the background will be smaller and more difficult to detect, even with current technology.

Edward Herrick-Gleason
Planetarium Director, Southworth Planetarium,
University of Southern Maine, Portland, Maine

Multiple space agencies are looking to send crewed missions to the Moon’s southern polar region in this decade and the next. Moreover, they intend to create the infrastructure that will allow for a sustained human presence, exploration, and economic development. This requires that the local geography, resources, and potential hazards be scouted in advance and navigation strategies that do not rely on a Global Positioning System (GPS) developed. On Sunday, April 21st, the Chinese Academy of Sciences (CAS) released the first complete high-definition geologic atlas of the Moon.

This 1:2.5 million scale geological set of maps provides basic geographical data for future lunar research and exploration. According to the Institute of Geochemistry of the Chinese Academy of Sciences (CAS), the volume includes data on 12,341 craters, 81 impact basins, 17 types of lithologies, 14 types of structures, and other geological information about the lunar surface. This data will be foundational to China’s efforts in selecting a site for their International Lunar Research Station (ILRS) and could also prove useful for NASA planners as they select a location for the Artemis Base Camp.

Ouyang Ziyuan and Liu Jianzhong, a research professor and senior researcher from the Institute of Geochemistry of the CAS (respectively), oversaw these efforts. Since 2012, they have led a team of over 100 scientists and cartographers from relevant research institutions. The team spent more than a decade compiling scientific exploration data obtained by the many orbiters, landers, and rovers that are part of the Chinese Lunar Exploration Program (Chang’e), and other research about the origin and evolution of the Moon.

According to the CAS, the atlas includes an “upgraded lunar geological time scale” for “objectively” depicting the geological evolution of the Moon, including the lunar tectonics and volcanic activity that once took place. As a result, the volume could not only be significant in terms of lunar exploration and site selection. Still, it could also improve our understanding of the formation and evolution of Earth and the other terrestrial planets of the Solar System – Mercury, Venus, and Mars. As Jianzhong indicated in a CAS press release,

“The world has witnessed significant progress in the field of lunar exploration and scientific research over the past decades, which have greatly improved our understanding of the moon. However, the lunar geologic maps published during the Apollo era have not been changed for about half a century and are still being used for lunar geological research. With the improvements of lunar geologic studies, those old maps can no longer meet the needs of future scientific research and lunar exploration.”

Jianzhong also claims that the atlas could help inform future sample collection on the Moon. This includes the Chang’e-6 mission (consisting of an orbiter and lander), which launched this past Friday (May 3rd). The orbiter element will reach the Moon in a few days, and the lander element is expected to touch down the far side of the Moon by early June. By 2026, it will be joined by the Chang’e-7 mission, consisting of an orbiter, lander, rover, and a mini-hopping probe. While Chang’e-6 will obtain lunar soil and rock samples, Chang’e-7 will investigate resources and obtain samples of water ice and volatiles.

According to Gregory Michael, a senior scientist from the Free University of Berlin, the release of this atlas represents the culmination of decades of work, and not just by Chinese scientists:

“This map, in particular, is the first on a global scale to utilize all of the post-Apollo era data. It builds on the achievements of the international community over the last decades, as well as on China’s own highly successful Chang’e program. It will be a starting point for every new question of lunar geology and become a primary resource for researchers studying lunar processes of all kinds.”

Aside from updating data on lunar features and geology, the new maps reportedly double the resolution of the Apollo-era maps. These maps were compiled by the US Geological Survey in the 1960s and 70s using data from the Apollo missions. Among them was a global map at the scale of 1:5,000,000, though other regional maps and those that showed the terrain near the Apollo landing sites were of higher resolution. Geological and geographical information on the Moon has advanced considerably since then, requiring updated maps that reflect the objective of returning to the Moon with the intent to stay.

In addition to the Geologic Atlas of the Lunar Globe, the CAS also released a book called Map Quadrangles of the Geologic Atlas of the Moon. This document includes 30 sector diagrams that collectively form a visualization of the entire lunar surface. Both are available in Chinese and English, have been integrated into a digital platform called Digital Moon, and will eventually become available to the international research community.

Further Reading: CAS

The first Hispanic woman to launch into space is now the second female astronaut to be awarded the United States’ highest honor.

Ellen Ochoa, who later directed NASA’s Johnson Space Center in Houston, was bestowed with the Presidential Medal of Freedom during a ceremony at the White House on Friday (May 3). Ochoa is the 10th astronaut to receive the medal.

“For most, the American dream is to be successful in whatever endeavor you choose here on Earth. For Dr. Ellen Ochoa, her dream was in the heavens,” said President Joe Biden, who presided over the ceremony. “Ellen was the first Hispanic woman to go to space, ushering in a whole new age of space exploration and what it means for every generation to reach for the stars.”

Individuals chosen for the Presidential Medal of Freedom have significantly contributed to the prosperity, values or security of the United States, world peace or other societal, public or private endeavors, according to the White House.

“Wow, what an unexpected and amazing honor!” said Ochoa, upon first hearing that she was going to be honored, according to a statement issued by NASA. “I’m so grateful for all my amazing NASA colleagues who shared my career journey with me.”

Related: Pioneering women in space: A gallery of astronaut firsts

Ochoa was working as a research engineer at NASA’s Ames Research Center in California when she was selected with the agency’s 13th group of astronauts in 1990. She flew on four space shuttle missions between 1993 and 2002, logging more than 40 days in Earth orbit.

During Ochoa’s first flight, STS-56, she used the space shuttle’s robotic arm to deploy and retrieve a satellite that observed the sun’s outer atmosphere, the corona. The mission was devoted to collecting data about the relationship between the sun’s energy output and Earth’s atmosphere and how those factors affected the planet’s ozone layer.

On her subsequent three missions, STS-66, STS-96 and STS-110, Ochoa continued to assist in the study of Earth’s atmosphere; she was among the first astronauts to enter the International Space Station; and later helped install a segment of the station’s backbone truss.

Ochoa was the 18th U.S. woman to launch into space and 22nd worldwide. She was the 295th person to leave Earth’s atmosphere and the 288th to enter orbit, as recorded in the Association of Space Explorers’ Registry of Space Travelers.

In 2013, Ochoa was named the 11th director of NASA’s Johnson Space Center, home to mission control and the U.S. astronaut corps. Only the second woman to hold the position, Ochoa served for five years, during which she oversaw the selection of the first crews to launch on commercial spacecraft and first yearlong mission aboard the International Space Station.

In addition to the Presidential Medal of Freedom, Ochoa has been recognized for her role in the U.S. space program with NASA’s highest award, the Distinguished Service Medal, and in 2017 was inducted into the U.S. Astronaut Hall of Fame in Florida. Schools bear her name today in California, New Jersey, Oklahoma, Texas and Washington.