Dr. John Barentine FRAS

Eternal Sunshine of the Spotless Sun

Well ahead of schedule according to where we're at in the current solar cycle, there are literally no sunspots on the solar disc today.

#Astronomy #Cycle25

Congratulations to the Roman Telescope team on first (science) light!

https://science.nasa.gov/blogs/roman/2026/09/15/nasa-activates-romans-primary-instrument-checks-out-coronagraph

#Astronomy

Don’t say there’s nothing new under the sun: meet McGetchin Crater, a lunar feature that's so fresh you might have to slap it.

#NASA scientists spotted this new crater, which formed sometime between April 11 and May 22, 2024, in routine images made by the Lunar Reconnaissance Orbiter spacecraft. It's the largest known recently formed crater in the Solar System. Researchers believe that a cratering event of this size on the Moon occurs only roughly once in ever 132 years.

Read more: https://science.nasa.gov/solar-system/moon/nasas-moon-orbiter-spots-new-once-in-century-moon-crater/

#Moon #PlanetaryScience

"The Exeter train delay is a fascinating story because it sits right at the point where emerging technologies first began to encounter the realities of the space environment."

https://www.space.com/astronomy/sun/space-weather-caused-a-16-minute-train-delay-in-1848-our-research-has-a-hint-of-a-detective-story

#SpaceWeather #SpaceEnvironment

If this result holds up, it’s potentially big: https://www.nature.com/articles/s41558-025-02481-0

In short, it implies that #LightPollution is decreasing the efficiency with which #plants remove carbon from the atmosphere. It concludes that artificial light at night increases “#ecosystem respiration” (plants, microbes, and animals releasing carbon dioxide through their activity and growth), but there is no corresponding increase in #photosynthesis.

The result is that plants exposed to ALAN emit more #carbon than they absorb from the #atmosphere. The authors write: “Our findings show that ALAN disrupts the fundamental energetic constraints on ecosystem metabolism, warranting the inclusion of light pollution in global change and carbon–climate feedback assessments.”

#ALAN

Pope Leo XIV today lamented light pollution, telling Vatican Observatory Foundation Board members "we have filled our skies with man-made light that blinds us to the lights God has placed there", evoking the words of his immediate predecessor.

Transcript: https://www.vatican.va/content/leo-xiv/en/speeches/2026/may/documents/20260511-vof.html

News item: https://www.vaticannews.va/en/pope/news/2026-05/pope-leo-xiv-vatican-observatory-foundation-science-faith.html

#Astronomy #Pope #Faith #DarkSkies

Is the Outer Space Treaty becoming a "League of Nations" for the cosmos?

In a new Opinion piece for Frontiers, we argue that existing space governance isn't fit for the era of private satellite megaconstellations. To protect our shared heritage, we need a shift toward "Space Environmentalism."

We still have the chance to build a future by design rather than by default—if we act before these norms are set in stone.

Read more: https://www.frontiersin.org/journals/space-technologies/articles/10.3389/frspt.2026.1748406/full

#SpacePolicy #Astronomy #SciencePolicy #SpaceEnvironmentalism

“'We’re all waiting. The mountain is a sacred space for us, and Hawaiians are really tired of having to fight military expansion in our home.'”

https://www.newsfromthestates.com/article/maui-residents-anxious-about-more-military-telescopes-atop-haleakal%C4%81

#Hawaii

"We conclude that satellites will be unavoidable during Square Kilometre Array observing conditions, risking a strong impact on the radiofrequency interference environment."

https://arxiv.org/abs/2604.22694

#Satellites #Astronomy #RadioAstronomy

On the front page of spaceweather.com today: "Last month, astronomer Gerald Rhemann attempted to photograph Comet Wierzchoś (C/2024 E1) during its closest approach to Earth. The comet was outnumbered 10:1 by #satellites.

"It's about to worsen. Right now, Earth is surrounded by almost 10,000 Starlinks with future plans calling for 42,000. Amazon’s Project Kuiper has begun launching its own planned 3,200-satellite broadband fleet, while China is building two more megaconstellations: Guowang (13,000 satellites) and "Qianfan" ("Thousand Sails", 15,000-plus). Together, they could eventually rival Starlink or even surpass it."

#Space #Astronomy

This morning's total #LunarEclipse as seen from Tucson, Arizona, in a three-image sequence.

I fed yesterday's #Artemis II "solar eclipse" image into astrometry.net to figure out which direction they were looking by obtaining a plate solution. The astronauts captured plenty of stars in order to be able to do exactly that.

https://www.nasa.gov/image-detail/amf-art002e009301/

"'[T]he crowding of orbit is not an accident waiting to happen. It is a manageable, predictable engineering workload and the argument worth making publicly is that regulators should be treating it that way, by asking for these numbers up front rather than reacting to headlines about near misses after the fact.'"

https://www.space.com/space-exploration/satellites/every-spacex-starlink-satellite-has-to-dodge-a-collision-almost-weekly-and-experts-fear-the-worst

#Satellites #Space #SpaceEnvironment

Nature Astronomy editorial: "With threats to #astronomy from all directions, we must consider the true value of astronomy. Astronomy educates the public; astronomy trains a data- and technology-centred workforce; astronomy supports other sciences, providing a laboratory to physicists and a chance to investigate other worlds to biologists and geologists; astronomy inspires curiosity and art and interest in science; astronomy involves big projects; astronomy gets people out into nature; astronomy is an international field, with global collegiality; astronomy adds to the repository of human knowledge. These are the aspects of astronomy that we should be regularly reminding our elected representatives about."

https://www.nature.com/articles/s41550-026-02830-9

"'This is not a hard number, like 99,999 is good and 100,001 is bad: clearly I’d prefer 50 000. But 100,000 causes losses at about the level of other technical losses, such as equipment failure.'"

https://petapixel.com/2026/07/28/no-more-than-100000-satellites-in-the-sky-if-we-want-to-preserve-astronomy/

#Space #Satellites #Astronomy #NightSky

This seems … problematic: commoditizing wasted outdoor light at night as a business opportunity. “These results demonstrate that an Ar + S atmosphere coupled with a carefully designed annealing profile provides a pathway toward high-voltage-output Sb2S3 thin-film solar cells, enabling BIPV systems to harvest low-intensity “waste” light, such as urban nighttime illumination, for hydrogen production via water splitting.”

https://onlinelibrary.wiley.com/doi/10.1002/smll.74447

#LightPollution #Environment #Energy

My colleague Nancy Clanton and I will put on an informative #webinar about residential #lighting (indoors and out!) next Wednesday, August 5, from 2pm-4pm EDT. Topics we will cover include:

Residential lighting fundamentals and design objectives

Evaluating natural light and daylighting strategies in residential spaces

Comparing ambient, task, and accent lighting applications

Selecting lighting fixtures and systems for functionality, aesthetics, and energy efficiency

Integrating lighting controls, automation, and smart home technologies

Designing exterior lighting for safety, usability, and curb appeal

Reviewing residential lighting codes, standards, and #sustainability considerations

American Institute of Architects (AIA) members and others may receive Continuing Education credit for attending this webinar.

Find out more and register for the event on: https://halfmoonseminars.org/product/webinars/residential-lighting-design-function-sustainability-and-energy-efficiency/

"As agencies turn priorities on paper into budget decisions, Sargent said the risk is that an application-focused model optimizes away the undirected science that has historically produced the most valuable surprises. 'If you try to centrally plan too much, then you might miss out on the kind of randomness of discovery,” Sargent said."

https://payloadspace.com/space-sciences-golden-age-problem/

#Space #SpacePolicy

"To approve [the Reflect Orbital #FCC application], after so many people, and so many experts like the ecologists, and scientific groups like the American Astronomical Society told you not to? It sure sounds arbitrary and capricious to me, and perhaps in this, when future litigation digs into that record, we might also find the kernel of its undoing."

https://joshuasokol.substack.com/p/diamonds-are-forever-forever-forever

#Space #SpaceEnvironmentalism #SunlightAsAService

#DarkSkies means jobs: “Northumberland National Park attracted 1.79 million visitors in 2025, contributing £146 million to the UK economy fueled by #astrotourism.”

https://streamlinefeed.co.ke/news/northumberland-national-park-records-1-79-million-visitors-in-post-covid-surge

#Tourism #Conservation #NationalParks #UnitedKingdom

PLAN-B's "Review of light and noise pollution impacts on terrestrial biodiversity and ecosystem services" is now published.

PDF: https://nora.nerc.ac.uk/id/eprint/541152/1/PLAN-B%20D1.1Review-Of-Light-And-Noise-Pollution-Impacts-On-Terrestrial-Biodiversity-And-Ecosystem-Services.pdf

#ALAN #LightPollution #Noise #EcosystemServices #Ecology #Pollution #Environment

New research shows our planet’s night is more volatile than ever.

A decade of satellite data reveals that while some areas are dimming due to policy changes or crisis, others are brightening at a rate that keeps the global average of light pollution rising by 2% annually.

It’s time to move from studying the glow to taking action. Read more: https://www.darkskyconsulting.com/blog/decoding-a-decade-of-rising-global-light-pollution

#DarkSkies #LightPollution #Science #Environment #NatureRestoration

From todays' APOD: "Can you find the comet? Somewhere through this web of satellite trails is Comet C/2025 R3 (PanSTARRS), a bright visitor passing through the inner Solar System. Now, the orbiting satellites themselves only appear as streaks because of the long camera exposure, over 10 minutes in this case."

https://apod.nasa.gov/apod/ap260427.html

"Despite the vast scale of the issue of light pollution, long-term research and widespread knowledge is lacking. I would therefore like to call on all readers to spread awareness about light pollution and related environmental issues that impact communities today. By taking collective action, society can work towards the transformation of the Anthropocene, into a posthumanist era where humans and nature collaborate to build homes in an entangled web of sacred mutualism. We could then create a sustainable world where environmental and animal rights become equal to human ones. This shift in thought may ultimately lead to a shift in action. So we might finally see the sky again."

https://www.diggitmagazine.com/light-pollution-anthropocene-environmental-cost-illumination

#Environment #LightPollution #Nature #RightsOfNature

New today in @Nature@mstdn.social: "Our findings challenge the prevailing perspective that changes in light radiance are largely gradual and unidirectional. Instead, the nightlights of Earth are surprisingly dynamic."

https://www.nature.com/articles/s41586-026-10260-w

And some reporting on the study and its implications by @skyandtelescope@bird.makeup: https://skyandtelescope.org/astronomy-news/light-pollution-is-increasingly-volatile-around-the-world/

#LightPollution #ALAN #ArtificialLightAtNight #RemoteSensing #DarkSkies #NighttimeLights

Astronomers for Planet Earth statement on both the pending Reflect Orbital and @SpaceX@mstdn.social 1M orbital data centers applications to the U.S. Federal Communications Commission: "A4E is firmly opposed to these projects, which compromise our field of interest, astronomy, and threaten the ecosystem and dark sky."

https://mailchi.mp/a3f870943c46/a4e-newsletter-q3-10346144

#Space #Satellites #SunlightAsAService #DataCenters #Environment #FCC

From @esoastronomy@mastodon.social's comment to the U.S. Federal Communication Commission on the #ReflectOrbital filing for clearance to operate an orbital sunlight reflector: “ESO expresses support for the submissions to the FCC by the global astronomical community and emphasises that the deployment of sunlight as a service will have far reaching implications to the #environment, and human health.”

#Astronomy #SunlightAsAService #Space #Satellites

Can we have vibrant cities AND #DarkSkies? Lighting designer Vellachi Ganesan shares how precision optics and smart tech are revolutionary advancements for creating better outdoor spaces and protecting the night sky.

http://www.darkskyconsulting.com/blog/vellachi-ganesan-interview-mar2026

#Lighting #OutdoorLighting #LightingDesign

Registration is open for IAU Symposium 409 ("Innovative Research and Techniques in Astronomy Communication") to be held in Tokyo and online 2-6 November 2026.

More information, registration, abstract submission and travel grant application links are on: https://iau.org/Iau/News/Ann2026/IAUS409.aspx

#Astronomy #Communication #SciComm #Conferences

This legislation, if signed into law by the U.S. President, will have a direct and harmful effect on conditions at a designated International Dark Sky Sanctuary.

The news item: https://apnews.com/article/mining-moratorium-boundary-waters-senate-vote-3e3f0827d52dd6d37f5e554b804ff27c

The legislation: https://www.congress.gov/bill/119th-congress/house-joint-resolution/140

The Sanctuary: https://darksky.org/places/boundary-waters-canoe-area-dark-sky-sanctuary/

The world is watching.

#DarkSkies #LightPollution #Environment #Congress

The bird-friendly “Addendum o” to ASHRAE 189.1 / International Green Construction Code is officially published. This is now available for jurisdictions to add on their own if they want, and it will be automatically incorporated into the full ASHRAE 189.1-2026 and 2027 IgCC.

Its scope statement now reads: “This section addresses requirements for building projects that pertain to site selection, site development, mitigation of heat island effect, light pollution reduction, bird-friendly design, and mitigation of transportation impacts.”

https://www.ashrae.org/file%20library/technical%20resources/standards%20and%20guidelines/standards%20addenda/189_1_2023_o_20260130.pdf

#LightPollution #Sustainability #Architecture

Some interesting history of #astronomy work by Fabio Falchi and co-workers showing that a modern adaptation of Ole Rømer's 17th century method of measuring the speed of light in vacuum yields a result within 1% of the modern value.

https://iopscience.iop.org/article/10.1088/1361-6404/ae3f66

#Physics

Thanks to @khulick@sciencemastodon.com for this great @skyandtelescope@bird.makeup piece on the @SpaceX@mstdn.social "one million orbital data centers" proposal.

"Let that number sink in for a moment. That’s 100 times more satellites than the company’s current Starlink constellation."

https://skyandtelescope.org/astronomy-news/spacex-aims-to-launch-1-million-ai-data-center-satellites/

#Space #Satellites #DataCenters #SpaceX #FCC