Connect with us

Published

on

Since time immemorial, humans around the world have gazed up in wonder at the night sky. The starry night sky has not only inspired countless works of music, art, and poetry but has also played an important role in timekeeping, navigation and agricultural practices in many traditions.

For many cultures, the night sky, with its stars, planets and the Milky Way, is considered just as important a part of the natural environment as the forests, lakes and mountains below. Countless people around the world gaze at the night sky: not only amateur and professional astronomers, but also casual observers who enjoy looking up at the stars to contemplate our place in the cosmos.

However, the night sky is changing. Not only is ground-based light pollution increasing rapidly, but growing numbers of satellites and space debris in orbit around Earth are also impacting the night sky.

Earlier research showed that satellites and space debris may increase the overall brightness of the night sky. In a new paper in Nature Astronomy, my colleagues and I applied this knowledge to predicting the performance of a major astronomical sky survey. We found this phenomenon may make the survey 7.5 percent less efficient and US$21.8 million (roughly Rs. 180 crore) more expensive.

A brighter sky

As a cultural astronomer, I am interested in the role of the night sky in cultural traditions around the world. In particular, I am interested in how light pollution and increasing satellite numbers affect different communities.

The number of satellites in orbit is growing rapidly. Since 2019, the number of functional satellites in orbit has more than doubled to around 7,600. The increase is mostly due to SpaceX and other companies launching large groups of satellites to provide high-speed internet communications around the world.

By the end of this decade, we estimate, there may be 100,000 satellites in orbit around the Earth. Collisions that generate space debris are more likely as space fills with new satellites. Other sources of debris include the intentional destruction of satellites in space warfare tests.

Increasing numbers of satellites and space debris reflect ever more sunlight towards the night side of Earth. This will almost certainly change the appearance of the night sky and make it harder for astronomers to do research.

One way satellites impact astronomy is by appearing as moving points of light, which show up as streaks across astronomers’ images. Another is by increasing diffuse night sky brightness. This means all the satellites that are too dim or small to be seen individually, as well as all the small bits of space debris, still reflect sunlight, and their collective effect is to make the night sky appear less dark.

Hard times for astronomers

In our research, we present the first published calculations of the aggregate effects of satellites and space debris in low-Earth orbit on major ground-based astronomy research facilities.

We looked at the effect on the planned large-scale survey of the night sky to be carried out at the Vera Rubin Observatory starting in 2024. We found that, by 2030, reflected light from objects in low-Earth orbit will likely increase the diffuse background brightness for this survey by at least 7.5 percent compared to an unpolluted sky.

This would diminish the efficiency of this survey by 7.5 percent as well. Over the ten-year lifetime of the survey, we estimate this would add some $21.8 million (roughly Rs. 180 crore) to the total project cost.

Brighter night skies mean longer exposures through telescopes are needed to see distant objects in the cosmos. This will mean that for projects with a fixed amount of observing time, less science will be accomplished, and there will be increased competition for telescope access.

In addition, brighter night skies will also reduce the detection limits of sky surveys, and dimmer objects may not be detected, resulting in missed research opportunities.

Some astrophysical events are rare and if researchers are unable to view them when they occur, there might not be an opportunity to easily see a given event again during a survey’s operational period. One example of faint objects is near-Earth objects – comets and asteroids in orbits close to Earth. Brighter night skies make it more likely such potentially hazardous objects may remain undetected.

A dramatic and unprecedented transformation

Increases in diffuse night sky brightness will also change how we see the night sky with the unaided eye. As the human eye cannot resolve individual small objects as well as a telescope can, an increase in satellites and space debris will create an even greater increase in the apparent brightness of the night sky. (When using a telescope or binoculars, one would be able to make out more of the dimmer satellites individually.) The projected increase in night sky brightness will make it increasingly difficult to see fainter stars and the Milky Way, both of which are important in various cultural traditions. Unlike “ground-based” light pollution (which tends to be the worst near large cities and heavily populated areas), the changes to the sky will be visible from essentially everywhere on Earth’s surface.

Our models give us a conservative lower limit for a likely increase in night sky brightness. If numbers of satellites and space debris continue to grow at the expected rate, the impacts will be even more pronounced.

As we note in our paper, “we are witnessing a dramatic, fundamental, and perhaps semi-permanent transformation of the night sky without historical precedent and with limited oversight”. Such a transformation will have profound consequences for professional astronomy as well as for anyone who wishes to view an unpolluted night sky.


From smartphones with rollable displays or liquid cooling, to compact AR glasses and handsets that can be repaired easily by their owners, we discuss the best devices we’ve seen at MWC 2023 on Orbital, the Gadgets 360 podcast. Orbital is available on Spotify, Gaana, JioSaavn, Google Podcasts, Apple Podcasts, Amazon Music and wherever you get your podcasts.
Affiliate links may be automatically generated – see our ethics statement for details.

Continue Reading

Science

Solar Sail Satellites Could Enhance Space Weather Forecasting and Alerts

Published

on

By

Solar Sail Satellites Could Enhance Space Weather Forecasting and Alerts

Satellites equipped with solar sails may soon improve early warnings for space weather events that could disrupt technological infrastructure on Earth. These sails, which harness light from the sun for propulsion, are being explored as a cost-effective alternative to traditional propulsion systems. Scientists believe this advancement could enhance monitoring of solar activity and provide earlier alerts for geomagnetic storms, reducing potential risks to power grids, satellites, GPS systems, and air traffic operations. Current space weather forecasting systems operate from a fixed point in space, but solar sail technology could allow satellites to move beyond conventional locations for improved data collection.

Advancement in Space Weather Forecasting

As reported by space.com, according to the National Oceanic and Atmospheric Administration’s (NOAA) Office of Space Weather Observations, which manages operational satellite systems, solar sails could allow spacecraft to travel beyond the Earth-sun Lagrange Point One (L1). This location, approximately 1.5 million kilometres from Earth, provides a stable position for solar observation. Irfan Azeem, Division Chief of the Research to Operations and Project Planning Division at NOAA, told Space.com that solar sails present a more efficient alternative to chemical propulsion, enabling satellites to move upstream of L1 for faster data retrieval. This could extend alert times for geomagnetic storms by up to 50 percent.

New Mission Underway

A project named Solar Cruiser, a collaboration between NOAA and NASA, is focused on developing a full-scale solar sail spacecraft. The sail, spanning 1,653 square metres, is designed to be deployed with four individual quadrants. NOAA has reported that the construction of the quadrants is expected to be completed by February 2026, with plans to secure a rideshare launch by 2029. Scientists are optimistic about the impact of this technology in space weather forecasting, as it could provide earlier detection of solar flares and coronal mass ejections, ultimately improving preparedness for disruptive space weather events.

For the latest tech news and reviews, follow Gadgets 360 on X, Facebook, WhatsApp, Threads and Google News. For the latest videos on gadgets and tech, subscribe to our YouTube channel. If you want to know everything about top influencers, follow our in-house Who’sThat360 on Instagram and YouTube.


OpenAI Will Not Launch o3 as Standalone AI Model in Favour of Unified GPT-5



New Downloads of DeepSeek Suspended in South Korea, Data Protection Agency Says

Related Stories

Continue Reading

Science

New Study Suggests Intelligent Life May Be More Common Than Thought

Published

on

By

New Study Suggests Intelligent Life May Be More Common Than Thought

A new study challenges the long-standing belief that intelligent life is an unlikely occurrence, suggesting that human-like evolution may be a natural outcome under the right planetary conditions. The research puts forward an alternative to the “hard steps” theory, which argues that the emergence of complex life is rare due to a series of improbable evolutionary leaps. Instead, the latest findings indicate that life evolves in response to planetary changes, making intelligent civilisations more probable than previously estimated. The study has been conducted by a team of experts, including astrophysicists and geobiologists, who assert that Earth’s environmental conditions played a crucial role in determining when complex life could emerge.

New Interpretation of Evolutionary Steps

According to a study published in Science Advances, the probability of intelligent life developing on other planets is higher than once believed. The research, led by Dan Mills, a postdoctoral researcher at The University of Munich, suggests that key evolutionary steps were not mere coincidences but rather responses to planetary changes. Mills explained that atmospheric oxygen levels, nutrient availability, and oceanic conditions dictated when complex organisms could thrive. He stated to Phys.org that Earth’s history was shaped by a sequence of “windows of habitability” that allowed life to advance in a systematic manner.

A Shift in Perspective

The widely accepted “hard steps” model, introduced by theoretical physicist Brandon Carter in 1983, argues that the emergence of intelligent beings is extremely rare. It is based on the premise that Earth’s evolutionary timeline was lengthy relative to the sun’s lifespan, making human-like intelligence an anomaly. However, the new research, co-authored by Jennifer Macalady, Professor of Geosciences at Pennsylvania State University, proposes that life progresses at a planetary timescale rather than an astrophysical one. Macalady told phys.org that rather than relying on astronomical predictions, geological factors should be considered to understand the evolution of life.

The findings suggest that if planetary conditions determine the timing of evolution, other planets may develop intelligent life at different rates. Jason Wright, Professor of Astronomy and Astrophysics at Pennsylvania State University and a co-author of the study, said that the framework increases the probability of detecting extraterrestrial life. He added that future research should focus on identifying biosignatures in exoplanetary atmospheres, such as oxygen and other life-supporting elements.

Future Research Directions

To assess the validity of this alternative model, researchers plan to examine whether previously assumed “hard steps” in evolution were truly rare occurrences. The study outlines proposals for experiments involving both unicellular and multicellular life forms under varying environmental conditions. The team suggests further investigation into whether certain evolutionary developments, such as oxygenic photosynthesis or the emergence of eukaryotic cells, have independently occurred multiple times throughout Earth’s history but were lost due to extinction events.

Continue Reading

Science

Giant Blobs Deep in Earth’s Mantle May Be Over a Billion Years Old

Published

on

By

Giant Blobs Deep in Earth’s Mantle May Be Over a Billion Years Old

Massive structures buried deep within the Earth’s mantle have been found to be more than a billion years old, according to recent research. These continent-sized formations, referred to as large low-seismic-velocity provinces (LLSVPs), are believed to be both older and hotter than their surrounding mantle. Situated at the boundary between the mantle and the outer core, approximately 3,000 kilometres beneath the Earth’s surface, these formations have puzzled scientists for decades. Their nature and origin have remained unclear, with seismic waves slowing down significantly when passing through them, suggesting distinct physical and compositional properties.

Blobs Deep Beneath Earth’s Surface

According to the study published in Nature, seismic data from over 100 significant earthquakes were analysed to understand these structures. As reported by space.com, Arwen Deuss, a seismologist at Utrecht University in the Netherlands, told Live Science that the primary observation has been the reduction in speed of seismic waves passing through these regions. However, an unexpected result was the reduced energy loss of these waves compared to the surrounding mantle, suggesting that factors beyond temperature influence these massive formations.

Role of Crystal Size in LLSVPs

Computer models have indicated that the mineral composition of these formations may be responsible for the observed phenomena. It has been proposed that the size of crystalline minerals within the LLSVPs plays a significant role. The research suggests that seismic waves lose energy when encountering grain boundaries between crystals. Smaller crystals result in increased energy loss due to the presence of more boundaries, whereas larger crystals cause lesser resistance. Deuss explained to Live Science that the surrounding mantle is composed of older tectonic plates that have broken into smaller fragments over time, whereas the LLSVPs contain much larger crystals that have remained undisturbed for extensive periods.

Implications for Earth’s Mantle and Surface

It has been suggested that these deep mantle structures have played a role in shaping the Earth’s surface. LLSVPs are believed to contribute to volcanic activity, with mantle plumes originating from these regions, bringing deep material to the surface. The composition of volcanic rocks worldwide could potentially be linked to these mantle formations, according to the study.

The age of these structures has been a subject of speculation, but the study provides substantial evidence supporting their billion-year existence. Deuss stated to Live Science that confirmation of their age allows for further exploration of their origins, stability, and long-term impact on Earth’s geological processes. Additional studies are expected to investigate how these formations have influenced the movement of tectonic plates and the overall behaviour of the mantle.

Continue Reading

Trending