A3veen.nl

Sterrenkundigen ontdekken de grootste superstructuur in het heelal / Unveiling the largest structures in the nearby Universe: Discovery of the Quipu superstructure - publication
2025-01-31
Wetenschappers hebben het grootste object in het heelal tot nu toe gevonden.
Quipu, zoals de superstructuur wordt genoemd, is een gigantisch lang snoer van clusters van sterrenstelsels, bij elkaar maar liefst 200 biljard zonsmassa (1 biljard is 10¹⁵) en 400 megaparsec lang, da’s 1,3 miljard lichtjaar. Quipu is een woord uit de Inca-taal en het heeft iets te maken met meten. Het onderzoek werd uitgevoerd door wetenschappers van het prestigieuze Max Planck Instituut in Duitsland en zij hebben deze superstructuur ontdekt, die bestaat uit afzonderlijke clusters en superclusters van sterrenstelsels, die allemaal gravitationeel met elkaar verbonden zijn. Naast Quipu zijn er nu nog vier andere superstructuren bekend, te weten Shapley, Serpens-Corona Borealis, Hercules en Sculptor-Pegasus.
Links:
Sterrenkundigen ontdekken de grootste superstructuur in het heelal: Quipu

I Heart Pluto Festival 2025
2025-02-13 - 2025-02-17
The 2025 I Heart Pluto Festival is an event celebrating the 95th anniversary of Pluto’s discovery on February 18, 1930, it is organized by Lowell Observatory.
February 18 marks the 95th anniversary of Pluto’s discovery in Flagstaff, Arizona and the 10th anniversary of the New Horizons spacecraft flyby of this storied planet. To celebrate, Lowell Observatory is hosting the Sixth Annual I Heart Pluto Festival from February 13-17, 2025 – themed “To Boldly Go Beyond New Horizons”.
Links:
I Heart Pluto Festival

Black Holes and Quantum Gravity (TV World Science Festival webcast)
2025-02-14 22:00 - 23:00 (Europe/Amsterdam)
Andrew Strominger, renowned for his work on black holes, string theory, and quantum gravity, joins Brian Greene to describe his latest results and how some of them may be testable by future observations.
This program is part of the Big Ideas series.
Links:
Black Holes and Quantum Gravity

A Spiral Structure in the Inner Oort Cloud - publication
2025-02-16
As the Galactic tide acts to decouple bodies from the scattered disk it creates a spiral structure in physical space that is roughly 15,000 au in length.
The spiral is long-lived and persists in the inner Oort cloud to the present time. In the pre-peer-reviewed paper ‘A Spiral Structure in the Inner Oort Cloud‘ scientists at the Southwest Research Institute discuss dynamics underlying the Oort spiral and (feeble) prospects for its observational detection.
Links:
NASA supercomputer finds billions of comets mimicking the Milky Way’s shape: ‘The universe seems to like spirals!’

Pluto : ontdekking (1930)
2025-02-18
Pluto is een dwergplaneet in de Kuipergordel, de voorlaatste zone van het zonnestelsel, en werd op 18 februari 1930 ontdekt door de Amerikaanse astronoom Clyde Tombaugh tijdens het vergelijken van fotografische platen met behulp van een blink comparator op het Lowell Observatory in Arizona gedurende een zoektocht naar een onbekende Planeet X in een baan buiten Neptunus, die was voorspeld door Percival Lowell.
De dwergplaneet is vernoemd naar de Romeinse god van de onderwereld, Pluto en werd tot 2006 geclassificeerd als de negende planeet. Hij heeft in de catalogus van planetoïden nummer 134340. De sterk excentrische baan van Pluto ligt grotendeels buiten die van de planeet Neptunus. Hij draait in 248 jaar om de zon en is gemiddeld bijna 40 maal zo ver ervan verwijderd als de Aarde. Pluto heeft vijf manen, waarvan de grootste – Charon – zoveel massa heeft dat Pluto en Charon rond een gemeenschappelijk zwaartepunt draaien dat buiten het oppervlak van Pluto zelf ligt, waardoor beide hemellichamen door sommigen als een dubbel-dwergplaneet worden gezien.
Links:
Alles wat je wil weten over dwergplaneet Pluto
Pluto Fact Sheet
I Heart Pluto Festival 2025
Is Pluto a planet or not? Who cares! Our love for the King of the Kuiper Belt is stronger than ever 95 years later

Detection of ferrihydrite in Martian red dust records ancient cold and wet conditions on Mars - publication
2025-02-25
Mars is widely known for its rusty red color — many people even refer to it as just the “Red Planet” — but research suggests the chemistry behind Mars’ rosy hue may actually hold important information.
For decades, spacecraft and rovers have gathered data pointing to a familiar explanation behind Mars’ redness: the rusting of iron minerals, namely iron oxide, in the planet’s dust. That’s the same compound that gives your standard “rust” on Earth its red color. Scientists already knew that on Mars, over billions of years, iron oxide has been ground into dust and carried across the planet by powerful winds, a process still shaping the Martian landscape today. However, not all iron oxides are the same, so experts have long debated the precise nature of Martian rust. Understanding how this rust formed offers a crucial glimpse into the planet’s past environment — was it once warm and wet, or always cold and dry? And, more importantly, did it ever support life?
Links:
What makes Mars the ‘Red’ Planet? Scientists have some new ideas

Planetenparade / Planetaire uitlijning 2025
2025-02-28
Links:
Planetenparade / Planetaire uitlijning 2024

SPHEREx - launch
2025-03-05 04:09 - 04:59
SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) is a future near-infrared space observatory that will perform an all-sky survey to measure the near-infrared spectra of approximately 450 million galaxies.
In February 2019, SPHEREx was selected by NASA for its next Medium-Class Explorers mission, beating out two competing mission concepts: Arcus and FINESSE. SPHEREx is scheduled to launch on March 5, 2025 at 04:09 (MET) on a Falcon 9 Block 5 rocket alongside the PUNCH microsatellites from Vandenberg Space Force Base. The principal investigator is James Bock at California Institute of Technology (Caltech) in Pasadena, California.
Links:
SPHEREx – NASA
Searching the entire sky for the secrets to our universe
An All-Sky Spectral Survey
How NASA’s SPHEREx Mission Will Share Its All-Sky Map With the World

Landelijke Sterrenkijkdagen 2025
2025-03-07 - 2025-03-09 | Nederland, Nederland
De Nederlandse sterrenwachten, planeteria en amateursterrenkundigen organiseren elk jaar de Landelijke Sterrenkijkdagen, belangstellenden krijgen de kans om met eigen ogen door telescopen naar hemellichamen te kijken.
Bij slecht weer is er een alternatief programma met lezingen, exposities, dia’s en informatie over sterrenkunde als hobby. De meeste sterrenwachten, een aantal Koninklijke Nederlandse Vereniging voor Weer- en Sterrenkunde (KNVWS) afdelingen en andere enthousiaste amateurs stellen in dat weekend hun deuren open om het geïnteresseerde publiek te laten kennismaken met sterrenkunde. Stichting ‘De Koepel’ te Utrecht was de coördinator van de landelijke Sterrenkijkdagen, vanaf 2014 is de KNVWS de coördinator.
Links:
Landelijke Sterrenkijkdagen
Landelijke Sterrenkijkdagen op 7, 8 en 9 maart 2025

Sporadic radio pulses from a white dwarf binary at the orbital period - publication
2025-03-12
In the past three years, astronomers have discovered a mysterious new type of radio source called these long period transients.
These objects emit bright radio signals that repeat every few minutes to every few hours. The astronomers have found about a dozen examples, but we still don’t understand which type of star could emit radio pulses in this peculiar way. In the research ‘Sporadic radio pulses from a white dwarf binary at the orbital period‘, the astronomers have discovered a new long period transient. Furthermore, they identified the stars responsible for the mysterious radio flashes – a breakthrough never achieved before.
Links:
Mysterious radio pulses from space have been tracked down – and the source is not what astronomers expected

Totale maansverduistering op 14 maart 2025
2025-03-14 07:26 - 08:33
Op vrijdag 14 maart 2025 vindt een totale maansverduistering plaats, een maansverduistering doet zich voor wanneer de Zon, de Aarde en de Maan op één lijn staan (met de Aarde in het midden), oftewel als Zon en Maan in oppositie staan.
Normaal weerkaatst de maan het licht van de zon naar de Aarde, maar tijdens een maansverduistering staat de aarde in de weg en ontvangt de Maan geen zonlicht: de Maan bevindt zich in de schaduw van de aarde en wordt dus donker, ofwel verduisterd. Maansverduisteringen treden in een patroon op. Deze zogenaamde Saros-cyclus herhaalt zich elke 18 jaar. In de Benelux is alleen het begin van de eclips zichtbaar. De verduistering heeft een grootte van 1.18 in de kernschaduw. Tijdens de totaliteit, die duurt van 07:26 tot 08:33, bevindt de Maan zich volledig in de kernschaduw van de Aarde en valt er geen direct zonlicht meer op de Maan. Echter, een beetje zonlicht valt door de aardatmosfeer en wordt gebroken, waardoor dit het maanoppervlak alsnog kan bereiken. Dit is met name rood licht, waardoor er een rode gloed over de Maan komt. Deze fase wordt in de volksmond ook wel Bloedmaan genoemd, en duurt bij deze eclips circa 67 minuten.
Links:
Totale maansverduistering op 14 maart 2025
The Next Full Moon is the Worm Moon
What to know about this week’s ‘blood worm moon’ total lunar eclipse
The Worm “Blood” Moon: Full Moon for March 2025

World Contact Day 2025
2025-03-15
World Contact Day was first declared in March 1953 by an organization called the International Flying Saucer Bureau (IFSB), as a day on which all IFSB members would attempt to send a telepathic message into space.
The IFSB voted to hold such a day in 1953, theorising that if both telepathy and alien life were real, a large number of people focussing on an identical piece of text may be able to transmit the message through space. IFSB members focused on the following message during 1953:
Calling occupants of interplanetary craft! Calling occupants of interplanetary craft that have been observing our planet EARTH. We of IFSB wish to make contact with you. We are your friends, and would like you to make an appearance here on EARTH. Your presence before us will be welcomed with the utmost friendship. We will do all in our power to promote mutual understanding between your people and the people of EARTH. Please come in peace and help us in our EARTHLY problems. Give us some sign that you have received our message. Be responsible for creating a miracle here on our planet to wake up the ignorant ones to reality. Let us hear from you. We are your friends.
The 1953 celebration is referenced in the song “Calling Occupants of Interplanetary Craft“, created in 1976 by Klaatu and later covered by The Carpenters.
Links:
Klaatu Track Facts
World Contact Day brings together E.T. enthusiasts from all over the world

JWST-TST High Contrast: Living on the Wedge, or, NIRCam Bar Coronagraphy Reveals CO2 in the HR 8799 and 51 Eri Exoplanets' Atmospheres - publication
2025-03-17
Astronomers have announced that the James Webb Space Telescope (JWST) has successfully captured its first direct images of carbon dioxide gas on a planet beyond the solar system, the findings are both a testament to the telescope’s power in direct imaging and provide valuable insights into how planets form, both within our solar system and across the universe.
The latest JWST observations focused on the HR 8799 system, which consists of four planets orbiting their host star about 130 light-years from Earth in the constellation Pegasus. Previous observations have shown four of them are more massive than Jupiter, and are in orbits with periods that range from decades to centuries. This system has long intrigued astronomers studying planet formation, largely because of its youth — at just 30 million years old, these planets still radiate leftover heat from their births, which JWST was able to observe in wavelengths that tease out the specific gases and other atmospheric details.
Links:
James Webb Space Telescope sees four giant alien planets circling nearby star

New DESI Results Strengthen Hints That Dark Energy May Evolve - publication
2025-03-19
The Dark Energy Spectroscopic Instrument (DESI) collaboration published an analysis of dark energy using their first three years of collected data, which spans nearly 15 million galaxies and quasars.
Researchers combined the DESI data with information from studies of the cosmic microwave background, supernovae, and weak gravitational lensing. The standard model of cosmology struggles to explain all the observations when taken together — but a model where dark energy’s influence changes over time seems to fit the data well. DESI is an international experiment with more than 900 researchers from over 70 institutions around the world and is managed by the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The collaboration shared their findings in multiple papers that will be posted on the online repository arXiv and in a presentation at the American Physical Society’s Global Physics Summit in Anaheim, California.
Links:
New DESI Results Strengthen Hints That Dark Energy May Evolve

Babelsberger Sternennächte – Sterne im Computertomographen | Dr. Axel Schwope (TV webcast)
2025-03-20 20:00 - 21:00
Die Leibniz-Instituts für Astrophysik Potsdam (AIP) Babelsberger Sternennächte finden online statt, in der Regel gibt es immer am 3. Donnerstag im Monat einen neuen Vortrag einer Wissenschaftlerin oder eines Wissenschaftlers des AIP, der ab 20 Uhr auf dem YouTube-Kanal von Urknall, Weltall und das Leben ausgestrahlt wird.
Links:
Babelsberger Sternennächte
Babelsberger Sternennächte – playlist

Can rotation solve the Hubble Puzzle? - publicatie
2025-03-21
A slowly spinning universe could solve the Hubble tension.
The study ‘Can rotation solve the Hubble Puzzle?‘ in Monthly Notices of the Royal Astronomical Society by researchers including István Szapudi of the University of Hawaiʻi at Mānoa Institute for Astronomy suggests the universe may rotate—just extremely slowly. The finding could help solve one of astronomy’s biggest puzzles. Current models say the universe expands evenly in all directions, with no sign of rotation. This idea fits most of what astronomers observe. But it doesn’t explain the so-called Hubble tension—a long-standing disagreement between two ways of measuring how fast the universe is expanding.
Links:
A slowly spinning universe could solve the Hubble tension
Een langzaam roterend heelal zou de Hubble spanning kúnnen oplossen

Livestream VSB -- Oneindigheid (TV webcast)
2025-03-21 20:00 - 22:00
Onmeetbaar en niet waarneembaar: oneindigheid is misschien wel één van de meest fascinerende concepten in de natuurwetenschap en filosofie.
“Hoe kan het heelal oneindig zijn?” is een vraag die het publiek ons met regelmaat stelt. Wat bedoelen astronomen met oneindig en hoe komen ze op dat idee? Christiaan Schriks neemt u mee om op deze onmogelijke, ongrijpbare en onvoorstelbare vraag toch iets van een ‘antwoord’ te geven.
Links:
Oneindigheid

Moon Dust to Mars Dreams: The Next Step Beyond Earth (TV webcast)
2025-03-21 21:00 - 22:00
Astronaut Woody Hoburg and leading planetary scientists join Brian Greene to explore ambitious new missions set to propel humanity deeper into space and sharpen our quest to discover life beyond Earth. This program is part of the Big Ideas series.
Links:
Moon Dust to Mars Dreams: The Next Step Beyond Earth

Witnessing the onset of reionization through Lyman-α emission at redshift 13 - publication
2025-03-26
Using the unique infrared sensitivity of NASA’s James Webb Space Telescope, researchers can examine ancient galaxies to probe secrets of the early universe.
An international team of astronomers has identified bright hydrogen emission from a galaxy in an unexpectedly early time in the universe’s history. The surprise finding is challenging researchers to explain how this light could have pierced the thick fog of neutral hydrogen that filled space at that time. The Webb telescope discovered the incredibly distant galaxy JADES-GS-z13-1, observed to exist just 330 million years after the big bang, in images taken by Webb’s NIRCam (Near-Infrared Camera) as part of the James Webb Space Telescope Advanced Deep Extragalactic Survey (JADES). Researchers used the galaxy’s brightness in different infrared filters to estimate its redshift, which measures a galaxy’s distance from Earth based on how its light has been stretched out during its journey through expanding space. The NIRCam imaging yielded an initial redshift estimate of 12.9. Seeking to confirm its extreme redshift, an international team lead by Joris Witstok of the University of Cambridge in the United Kingdom, as well as the Cosmic Dawn Center and the University of Copenhagen in Denmark, then observed the galaxy using Webb’s Near-Infrared Spectrograph instrument. In the resulting spectrum, the redshift was confirmed to be 13.0.
This equates to a galaxy seen just 330 million years after the big bang, a small fraction of the universe’s present age of 13.8 billion years old. But an unexpected feature stood out as well: one specific, distinctly bright wavelength of light, known as Lyman-alpha emission, radiated by hydrogen atoms. This emission was far stronger than astronomers thought possible at this early stage in the universe’s development. Before and during the era of reionization, the immense amounts of neutral hydrogen fog surrounding galaxies blocked any energetic ultraviolet light they emitted, much like the filtering effect of colored glass. Until enough stars had formed and were able to ionize the hydrogen gas, no such light — including Lyman-alpha emission — could escape from these fledgling galaxies to reach Earth. The confirmation of Lyman-alpha radiation from this galaxy, therefore, has great implications for our understanding of the early universe. The source of the Lyman-alpha radiation from this galaxy is not yet known, but it may include the first light from the earliest generation of stars to form in the universe. A powerful active galactic nucleus, driven by one of the first supermassive black holes, is another possibility identified by the team.
Links:
NASA’s Webb Sees Galaxy Mysteriously Clearing Fog of Early Universe

Gedeeltelijke Zonsverduistering van 29 maart 2025 / Partial Solar Eclipse
2025-03-29 11:17 - 13:04
Een zonsverduistering (of zoneclips) is een astronomisch verschijnsel waarbij de maan vanuit de aarde gezien de zon geheel of gedeeltelijk bedekt.
Zonsverduisteringen vinden plaats als de Aarde, Maan en Zon vrijwel op een lijn staan, met de Maan in het midden. Een zonsverduistering kan slechts op een deel van de Aarde worden waargenomen. De schaduw van de Maan vormt (min of meer) een ellips op het aardoppervlak, maar zal (min of meer) cirkelvormig zijn wanneer de schaduwkegel haaks op het aardoppervlak staat. Een totale verduistering is te zien waar de slagschaduw, dit wordt ook wel kernschaduw of umbra genoemd, van de Maan het aardoppervlak raakt. Er is dan sprake van een totaliteitszone. Een gedeeltelijke verduistering is te zien waar de halfschaduw, die ook wel penumbra genoemd wordt, van de Maan het aardoppervlak raakt. Bij deze laatste is er slechts een hap zichtbaar uit de Zon. Niet bij elke zonsverduistering raakt de kernschaduw van de Maan de Aarde; in dat geval is er nergens op aarde een totale verduistering te zien, maar enkel een gedeeltelijke. Een ringvormige zonsverduistering is een bijzondere variant van een gedeeltelijke zonsverduistering. De baan van de Maan om de Aarde is niet precies cirkelvormig, waardoor de Maan soms iets dichter bij, soms wat verder af van de Aarde staat. In het laatste geval kan het voorkomen dat de Maan slechts het middelste gedeelte van de Zon afdekt. Er is dan een ringvormige zonsverduistering te zien. Een bijzonder soort zonsverduistering doet zich voor wanneer een zonsverduistering in bepaalde gebieden totaal is en in andere gebieden als ringvormig wordt waargenomen. Er is dan sprake van een ringvormige/totale of hybride zonsverduistering.
Op zaterdag 29 maart 2025, tussen 11:17 en 13:04, vindt een gedeeltelijke zonsverduistering plaats. Bij helder weer zal vanuit Nederland en België de hele verduistering zichtbaar zijn. Je ziet de eclips als een hap die in eerste instantie uit de rechterkant van de Zon wordt genomen en steeds groter wordt. Halverwege de verduistering bevindt die hap zich aan de bovenkant, en tegen het einde van de eclips verdwijnt deze aan de linkerkant van de Zon. De verduistering duurt in de Benelux 1,8 uur. Tijdens het maximum van de eclips, om 12:10, zal 36% van de diameter van de Zon, ofwel 24% van haar oppervlakte, bedekt zijn. De Zon staat op dat moment 41° boven de zuidzuidoostelijke horizon en het maximum van de eclips is in onze streken goed zichtbaar. Aangezien de Maan ten noorden langs de Zon trekt, wordt de verduistering groter naarmate je je noordelijker bevindt. Zie de lokale gegevens voor een aantal plaatsen in de Benelux. Een bedekking van 24% is niet voldoende om het donker te maken in onze streken, maar meer dan genoeg om te worden opgemerkt met het blote oog (zonder vergroting, maar met bescherming). Daarnaast heeft de reductie aan zonlicht invloed op bijvoorbeeld de energieopwekking door zonnepanelen.
Links:
Partial Solar Eclipse Watch
Zonsverduistering van 29 maart 2025
Zonsverduistering op 29 maart 2025
Gedeeltelijke zonsverduistering
NASA website met historische en toekomstige verduisteringen
Interactive Google Maps over zonsverduisteringen
Zonsverduistering 2025 – Wat is het en wanneer vindt de volgende plaats?
Volkssterrenwacht Bussloo – Speciale openstelling

#GAM2025 Global Astronomy Month 2025
2025-04-01 - 2025-04-30
Inspired by the 100 hours of astronomy, this annual offshoot began upon the inception of Astronomers Without Borders and remains one of its flagship programs.
A mix of various programs ranging from Astro Arts to Observational Programs, this festival runs the whole month of April and features partners that creates a larger community of astronomy enthusiasts that span the globe.
Links:
Global Astronomy Month 2025

Babelsberger Sternennächte – Hunting for hidden X-ray treasures in Space | Dr. Iris Traulsen (TV webcast)
2025-04-01 20:00 - 21:00
Die Leibniz-Instituts für Astrophysik Potsdam (AIP) Babelsberger Sternennächte finden online statt, in der Regel gibt es immer am 3. Donnerstag im Monat einen neuen Vortrag einer Wissenschaftlerin oder eines Wissenschaftlers des AIP, der ab 20 Uhr auf dem YouTube-Kanal von Urknall, Weltall und das Leben ausgestrahlt wird.
Dr. Iris Traulsen nimmt das Publikum mit „Auf die Suche nach den Röntgenstrahlern im All“. Mit der überraschenden Entdeckung von Röntgenstrahlen aus dem Weltraum in den 1960er Jahren und der folgenden Entwicklung von astronomischen Röntgendetektoren öffnete sich ein neues Fenster ins Universum: Im Röntgenlicht sind energiereiche, exotische Prozesse zu sehen. Dieses “kosmische Labor” lässt uns noch unbekannte Eigenschaften bereits bekannter astronomischer Objekte wie auch noch unbekannte Arten von Objekten entdecken. Die Europäische Weltraumagentur ESA betreibt die große satellitengestützte Röntgenmission XMM-Newton, die seit Januar 2000 wissenschaftliche Beobachtungen durchführt. Seit etwa 20 Jahren arbeitet Iris Traulsen mit den XMM-Newton-Daten und berichtet, dass sich darin viele noch unbekannte astronomische Röntgenstrahler verbergen. Wie lassen sich diese aufspüren und für die Wissenschaft zugänglich machen? Der Vortrag lädt dazu ein, ins wissenschaftliche Team hinter den Kulissen eines Weltraumteleskops zu blicken und tiefer ins “heiße Universum“ einzutauchen.
Links:
Babelsberger Sternennächte
Babelsberger Sternennächte – playlist

#HumanSpaceFlightDay / Dag van de Ruimtevaart 2025
2025-04-12
The UN General Assembly, in its resolution A/RES/65/271 of 7 April 2011, declared 12 April as the International Day of Human Space Flight “to celebrate each year at the international level the beginning of the space era for mankind, reaffirming the important contribution of space science and technology in achieving sustainable development goals and increasing the well-being of States and peoples, as well as ensuring the realization of their aspiration to maintain outer space for peaceful purposes.”
12 April 1961 was the date of the first human space flight, carried out by Yuri Gagarin, a Soviet citizen. This historic event opened the way for space exploration for the benefit of all humanity. The General Assembly expressed its deep conviction of the common interest of mankind in promoting and expanding the exploration and use of outer space, as the province of all mankind, for peaceful purposes and in continuing efforts to extend to all States the benefits derived there from.
Links:
Day of Human Space Flight 12 April
World Space Week

The Sky at Night – Asteroid Strike? (TV BBC Four)
2025-04-14 23:00 - 23:30
The Sky at Night is a monthly documentary television programme on astronomy produced by the BBC.
The show had the same permanent presenter, Patrick Moore, from its first broadcast on 24 April 1957 until 7 January 2013. The latter date was a posthumous broadcast, which followed Moore’s death on 9 December 2012. This made it the longest-running programme with the same presenter in television history. Many early episodes are missing, either because the tapes were wiped, thrown out, or because the episode was broadcast live and never recorded in the first place. Beginning with the 3 February 2013 edition, the show was co-presented by Lucie Green and Chris Lintott. Since December 2013 Maggie Aderin-Pocock has been a presenter. The programme’s opening and closing theme music is “At the Castle Gate”, from the incidental music to Pelléas et Mélisande, written in 1905 by Jean Sibelius, performed by the Royal Philharmonic Orchestra and conducted by Sir Thomas Beecham.
This episode:
The team explore one of the biggest stories in space news, the ‘city killer’ asteroid 2024 YR4. First observed on 27 December 2024, it soon became one of the biggest threats from an asteroid ever detected, with the potential to cause a heat blast that could vaporise solid rock, wind blasts five times the speed of the strongest hurricane and a shockwave that would flatten buildings and trees for hundreds of miles. This was a potential natural disaster we needed to respond to as a planet. So how well did we do? Our team of presenters are on hand to find out, and while YR4 was later downgraded to a near miss, what has it told us about our ability to react when an asteroid strike is on its way? George Dransfield kicks off, talking us through the damage an asteroid like YR4 could do and why some say we are overdue an asteroid strike of this size. But how will we know if it’s truly on its way? Chris Lintott meets Dr Meg Schwamb at a football pitch – which it turns out is the perfect place to explain how the probability of a strike is calculated. Following the same highs and lows they do when a ball just misses the goal, they explain why the probability of asteroid 2024 YR4 hitting earth first rose so quickly before it fell. It turns out it wasn’t the maths being wrong!
Luckily, next time the numbers say an asteroid impact is on its way, we do have ways of defending ourselves, Maggie Aderin-Pocock takes a tea break to explain some of the options, from nudging it to nuking it – they all have their pros and cons. But to know our best plan of action, we need to understand more about the asteroids, and George meets up with Dr Carly Howett to find out how Nasa’s Lucy Mission could provide us with invaluable information for any future strikes. With this wealth of information about any potential asteroids heading our way, Maggie meets Prof Hugh Lewis in Southampton to discover how the international community is set up to respond to any future threats, and to find out who will decide what action to take and the possible consequences it may have. But the skies and the asteroids in it aren’t just a scary threat to humanity; when we stop and look up, there are some beautiful sights to be seen, and Pete Lawrence is on hand to tell us what to look out for in the coming months. Join us for an exciting episode that looks beyond the headlines, to see what efforts were made to protect us from an asteroid that could have wiped out a city the size of Greater London – and beyond.
Links:
The Sky at Night

Strongest hints yet of biological activity outside the solar system / New Constraints on DMS and DMDS in the Atmosphere of K2-18 b from JWST MIRI - publication
2025-04-17
Astronomers have detected the most promising signs yet of a possible biosignature outside the solar system, although they remain cautious.
Using data from the James Webb Space Telescope (JWST), the astronomers, led by the University of Cambridge, have detected the chemical fingerprints of dimethyl sulfide (DMS) and/or dimethyl disulfide (DMDS), in the atmosphere of the exoplanet K2-18b, which orbits its star in the habitable zone. On Earth, DMS and DMDS are only produced by life, primarily microbial life such as marine phytoplankton. While an unknown chemical process may be the source of these molecules in K2-18b’s atmosphere, the results are the strongest evidence yet that life may exist on a planet outside our solar system. The observations have reached the ‘three-sigma’ level of statistical significance – meaning there is a 0.3% probability that they occurred by chance. To reach the accepted classification for scientific discovery, the observations would have to cross the five-sigma threshold, meaning there would be below a 0.00006% probability they occurred by chance. The researchers say between 16 and 24 hours of follow-up observation time with JWST may help them reach the all-important five-sigma significance. Their results are reported in The Astrophysical Journal Letters. Earlier observations of K2-18b — which is 8.6 times as massive and 2.6 times as large as Earth, and lies 124 light years away in the constellation of Leo — identified methane and carbon dioxide in its atmosphere. This was the first time that carbon-based molecules were discovered in the atmosphere of an exoplanet in the habitable zone.
Those results were consistent with predictions for a ‘Hycean’ planet: a habitable ocean-covered world underneath a hydrogen-rich atmosphere. However, another, weaker signal hinted at the possibility of something else happening on K2-18b. To determine the chemical composition of the atmospheres of faraway planets, astronomers analyse the light from its parent star as the planet transits, or passes in front of the star as seen from the Earth. As K2-18b transits, JWST can detect a drop in stellar brightness, and a tiny fraction of starlight passes through the planet’s atmosphere before reaching Earth. The absorption of some of the starlight in the planet’s atmosphere leaves imprints in the stellar spectrum that astronomers can piece together to determine the constituent gases of the exoplanet’s atmosphere. The earlier, tentative, inference of DMS was made using JWST’s NIRISS (Near-Infrared Imager and Slitless Spectrograph) and NIRSpec (Near-Infrared Spectrograph) instruments, which together cover the near-infrared (0.8-5 micron) range of wavelengths. The new, independent observation used JWST’s MIRI (Mid-Infrared Instrument) in the mid-infrared (6-12 micron) range. DMS and DMDS are molecules from the same chemical family, and both are predicted to be biosignatures.
Both molecules have overlapping spectral features in the observed wavelength range, although further observations will help differentiate between the two molecules. However, the concentrations of DMS and DMDS in K2-18b’s atmosphere are very different than on Earth, where they are generally below one part per billion by volume. On K2-18b, they are estimated to be thousands of times stronger – over ten parts per million. Madhusudhan says that while the results are exciting, it’s vital to obtain more data before claiming that life has been found on another world. He says that while he is cautiously optimistic, there could be previously unknown chemical processes at work on K2-18b that may account for the observations. Working with colleagues, he is hoping to conduct further theoretical and experimental work to determine whether DMS and DMDS can be produced non-biologically at the level currently inferred. While he is not yet claiming a definitive discovery, Madhusudhan says that with powerful tools like JWST and future planned telescopes, humanity is taking new steps toward answering that most essential of questions: are we alone? The James Webb Space Telescope is a collaboration between NASA, ESA and the Canadian Space Agency (CSA). The research is supported by a UK Research and Innovation (UKRI) Frontier Research Grant.
Links:
Strongest hints yet of biological activity outside the solar system
Wetenschappers vinden ‘sterkste tekenen tot nu toe’ van mogelijk buitenaards leven
Er is geen Planet K2-18B! bescherm het buitenaardse leven!

Babelsberger Sternennächte – Solar Orbiter – Röntgenblick auf die Sonne / Das Röntgenteleskop STIX | Dr. Iris Traulsen (TV webcast)
2025-04-17 20:00 - 21:00
Die Leibniz-Instituts für Astrophysik Potsdam (AIP) Babelsberger Sternennächte finden online statt, in der Regel gibt es immer am 3. Donnerstag im Monat einen neuen Vortrag einer Wissenschaftlerin oder eines Wissenschaftlers des AIP, der ab 20 Uhr auf dem YouTube-Kanal von Urknall, Weltall und das Leben ausgestrahlt wird.
Röntgenblick auf die Sonne:
In diesem Vortrag geht es um wissenschaftliche Ergebnisse, die u.a. mit dem Röntgenteleskop STIX an Bord des Solar Orbiter gewonnen wurden. Die ESA-Raumsonde Solar Orbiter kreist seit 2020 um die Sonne und untersucht sie mittels zehn verschiedener Instrumente an Bord. STIX beobachtet die heißesten Regionen und energiereichsten Prozesse in Sonneneruptionen. Über die letzten Jahre hinweg ist die Sonnenaktivität stetig angestiegen, so dass Forschende bereits über 70,000 dieser Strahlungsausbrüche beobachten konnten. Ein Schwerpunkt der Forschung liegt auf der Kombination von STIX mit anderen Instrumenten. So haben die Wissenschaftlerinnen und Wissenschaftler z.B. die ersten 3D-Bilder von Sonneneruptionen im Röntgenbereich erzeugt. Mit STIX und anderen Instrumenten auf Solar Orbiter untersuchen sie außerdem das Material, das von der Sonne weggeschleudert wird, insbesondere energiereiche Teilchen und Plasmawolken, und welche Konsequenzen daraus für die Erde und das Weltraumwetter folgen.
Das Röntgenteleskop STIX:
Hier können Interessierte hinter die technischen Kulissen des Röntgenteleskops STIX schauen. Dr. Alexander Warmuth geht in diesem Vortrag auf verschiedene Fragen ein: Wie funktioniert eigentlich so ein Röntgenteleskop? Wie erzeugt es Röntgenbilder der Sonne, obwohl die Strahlung so energiereich ist, dass in dem Teleskop weder Linsen noch Spiegel verwendet werden können? Was sind die Anforderungen an ein Instrument, welches sich stärker der Sonne annähert als der sonnennächste Planet Merkur?
Links:
Babelsberger Sternennächte
Babelsberger Sternennächte – playlist

Meteorenzwerm α-Virginiden in april 2025
2025-04-18 05:00 - 17:00
De meteorenzwerm α-Virginiden bereikt op vrijdag 18 april 2025, rond 05:00, zijn maximum.
Wanneer de radiant in het zenit zou staan, zouden er van deze zwerm naar verwachting gemiddeld zo’n 5 meteoren per uur vallen. Rond 01:00 staat de radiant van de zwerm in het hoogste punt (op 36°) aan de hemel. Er is dan bij ons ieder uur slechts een enkele meteoor van deze zwerm zichtbaar. Samen met meteoren van andere zwermen, en sporadische meteoren, zijn er bij donkere, heldere hemel in totaal circa 3–8 meteoren per uur zichtbaar. Op een goed donkere plek zijn ongeveer drie keer zoveel meteoren zichtbaar als in een grote stad. De Maan komt om 02:19 op, is voor ongeveer 80% verlicht en kan flink storen; de zwakkere meteoren zullen hierdoor dit jaar niet zichtbaar zijn. Waarnemen voor de opkomst van de Maan kan dus gunstig zijn. Rond 06:00 gaat het schemeren en om 06:36 komt de Zon op. Over het algemeen zijn de de meteoren van een zwerm niet alleen op de dag van het maximum zichtbaar. Zo is gedurende circa 9 dagen rondom het maximum ruim de helft van het maximale aantal meteoren (1 per uur) van de α-Virginiden te zien. Tot 7 dagen voor en na het maximum zijn nog meteoren van deze zwerm te herkennen. Er zijn dus nog meer kansen, voor het geval het in de nacht van het maximum niet helder is. Iedere dag verder weg van het maximum zijn er echter wel ongeveer 20% minder meteoren per uur te zien. De typische snelheden van de meteoren in deze zwerm zijn met circa 17 km/s (ongeveer 60.120 km/uur) relatief laag. Er is geen speciale apparatuur nodig om meteoren waar te kunnen nemen.
Links:
Meteorenzwerm α-Virginiden in april 2025

A Search for Planet Nine with IRAS and AKARI Data - publication
2025-04-24
Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart, if the object really is Planet Nine, it would be larger than Neptune and exist 700 times further from the sun than Earth.
Phan and Goto used sky surveys from two infrared space telescopes launched 23 years apart: the Infrared Astronomy Satellite (IRAS), a NASA-Netherlands-U.K. satellite launched in 1983; and AKARI, a Japanese satellite launched in 2006. Because of Planet Nine’s long orbit, the researchers hypothesized that the time gap between the two data sets would be enough to see the potential planet move incrementally across the night sky. From an initial catalog of about 2 million objects within the IRAS and AKARI data sets, the researchers whittled down to pairs of dots of light whose spacing could be explained by a moving planet with a Planet Nine–like mass and distance. Then, they removed known sources such as stars, sources that didn’t move over time, and sources with too much noise, such as those near the bright galactic center. When 13 pairs remained, they checked each by eye. Only one candidate pair survived the scrutiny. The two dots had matching colors and brightnesses—a sign they were the same object.
Links:
Astronomers searching for Planet Nine find possible hints of different planet
Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

Biomass : ESA's forest mission
2025-04-29 - 2030-04-29
Biomass is an Earth observing satellite planned for launch by the European Space Agency (ESA) on 29 April 2025 from Kourou, French Guiana on a Vega C launch vehicle, the mission will provide the first comprehensive measurements of global forest biomass.
It is meant to last for five years, monitoring at least eight growth cycles in the world’s forests. The Biomass satellite is part of ESA’s Living Planet Programme, which consists of Earth observation missions. Its initial launch date was set to 2020, but that has since been delayed to 2025. The entire cost of the mission was placed at around 400 million euros. The main scientific instrument aboard Biomass will be a synthetic aperture radar (SAR) operating at 435 MHz. The satellite will measure 10 x 12 x 20m, weigh around 1.2 tonnes and it is set to orbit the Earth at an altitude of 666 km. All devices for assembly of the satellite structure, including vertical transport equipment, assembly and disassembly of satellite panels, assembly and disassembly of the Synthetic Aperture Radar are done by the Spanish company SENER.
Links:
Biomass – ESA
#ForestDay #IntlForestDay Day of Forests / Dag van het Bos 2025 (TV FAO webcast)

Cosmos 482 lander probe is expected to reenter Earth's atmosphere
2025-05-07 - 2025-05-13
The orbit of the Kosmos 482 (Russian: Космос 482 meaning Cosmos 482) lander probe is decaying and it is expected to reenter Earth’s atmosphere some time from May 9 to May 10, 2025, centered on roughly May 10 at 09:30 (07:30 UTC).
Because the probe was designed to withstand entry into the Venus atmosphere, it is possible the probe (or parts of it) will survive reentry at Earth and reach the surface. Kosmos 482, launched March 31, 1972, at 04:02:33 UTC, was an attempted Venus probe which failed to escape low Earth orbit. Its landing module, which weighs 495 kilograms, is highly likely to reach the surface of Earth in one piece as it was designed to withstand 300 G’s of acceleration and 100 atmospheres of pressure. Beginning in 1962, the name Kosmos was given to Soviet spacecraft which remained in Earth orbit, regardless of whether that was their intended final destination. The designation of this mission as an intended planetary probe is based on evidence from Soviet and non-Soviet sources and historical documents. Typically Soviet planetary missions were initially put into an Earth parking orbit as a launch platform with a rocket engine and attached probe. The probes were then launched toward their targets with an engine burn with a duration of roughly four minutes. If the engine misfired or the burn was not completed, the probes would be left in Earth orbit and given a Kosmos designation. Kosmos 482 was launched by a Molniya booster on March 31, 1972, four days after the Venera 8 atmospheric probe and may have been similar in design and mission plan. After achieving an Earth parking orbit, the spacecraft made an apparent attempt to launch into a Venus transfer trajectory. It separated into four pieces, two of which remained in low Earth orbit and decayed within 48 hours into south New Zealand and two pieces (presumably the payload and detached engine unit) went into a higher 210 km × 9,800 km, 52 deg inclination orbit.
An incorrectly set timer caused the Blok L stage to cut off prematurely, preventing the probe from escaping Earth orbit. The first of these pieces, four red-hot 13.6-kilogram titanium alloy spheres, with a diameter of 38 centimetres, landed within a 16-kilometre (10 mi) radius of each other just outside Ashburton, New Zealand at 1:00 AM on April 3, 1972. The spheres scorched holes in crops and made deep indentations in the soil, but no one was injured. A similarly shaped object was discovered near Eiffelton, New Zealand, in 1978. Space law required that the space junk be returned to its national owner, but the Soviets denied knowledge or ownership of the satellite. Ownership therefore fell to the farmer upon whose property the satellite fell. The pieces were thoroughly analyzed by New Zealand scientists which determined that they were Soviet in origin because of manufacturing marks and the high-tech welding of the titanium. The scientists concluded that they were probably gas pressure vessels of a kind used in the launching rocket for a satellite or space vehicle and had decayed in the atmosphere. The last remaining piece in orbit, the descent craft, reentered on 10 May, somewhere between 51.95 degrees north or south latitude. As of 10 May 2025, the European Space Agency reported that the descent craft was not detected by radar during a predicted pass over Germany at 07:32 UTC (09:32 CEST). Based on this, ESA concluded that reentry most likely already occurred earlier that morning. Later that day, the Russian space agency Roscosmos stated that the lander had harmlessly impacted the eastern Indian Ocean at 06:24 UTC west of Jakarta, Indonesia. The impact time and location given by Roscosmos may not be fully accurate.
Links:
Cosmos 482 – NASA NSSDCA Master Catalog
Old Soviet spacecraft to fall to Earth in early May 2025
Cosmos 482 landing module – Zichtbare passages
Objekt Live Tracking
More than 50 years after trying to reach Venus, a failed Soviet spacecraft is about to return to Earth
Kosmos 482 Descent Craft reentry forecasts
