Indholdsfortegnelse for December 2025 i BBC Sky at Night

How did Earth come to host such an extraordinary abundance of life? It's a question that many branches of science have tried to answer. In astronomy, one theory suggests life didn't begin here at all – it arrived from space, hitching a ride on comets or asteroids. This idea, known as panspermia, isn't new. First put forward in the 19th century, it has gained ground as recent research, including sample-return missions, have brought fresh ways to test it. Join Nick Spall on page 67 as he explores the evidence. Back in the late 1800s, we only knew about 500 or so asteroids in the Solar System. Today, that number has soared past 1.4 million! And thanks to smart telescopes, it's now easier than ever for amateur stargazers to get involved…

Find it at www.skyatnightmagazine.com/bonus-content DECEMBER HIGHLIGHTS Webb's ‘impossible’ black holes Seb Hoenig reveals how studies of the early Universe could show that JWST has got black holes all wrong. Your best images of the Universe Our extended gallery featuring the best astro images sent to us by BBC Sky at Night Magazine readers. Download the full Messier Catalogue Download our guide to Messier objects to your phone or tablet, with coordinates to find each one with your telescope. The Virtual Planetarium…

Observatories based on Earth have a constant problem: our atmosphere distorts starlight as it makes its way to the ground. That's why we put telescopes in space to avoid the interference. Now, researchers at Johns Hopkins University have come up with a mathematical solution that could give ground-based telescopes near space-quality vision. Called ImageMM, the algorithm models how light travels from the stars and how it's influenced by our atmosphere. “Think of the atmosphere as a restless sheer curtain, constantly shifting and shimmering, so the scene behind it always looks blurred,” says Yashil Sukurdeep, who helped develop the algorithm. “Our algorithms learn to see past that curtain, reconstructing the still, sharp image hidden behind it.” “By sharpening our view of the sky, we can see farther, fainter targets and push…

When the OSIRIS-REx spacecraft returned its sample of asteroid Bennu to Earth, scientists around the world scrambled to get their hands on its precious cargo. The early results justify their excitement: Bennu, which is believed to be largely unaltered since the early days of the Solar System, has surprisingly complex chemistry. Even molecules as complex as amino acids appear to be liberally sprinkled throughout. Results like these have intensified interest in the chemistry that takes place in protoplanetary discs, where objects like Bennu – and Earth – form. If complex molecules form naturally in such conditions, then it's possible that the ingredients for life could be delivered to newly formed and forming planets. To understand the soup of chemicals we now expect in protoplanetary discs, we rely on a plucky…

In 2024, SpaceX was responsible for just over half of the world's orbital launches, a market share that's expected to climb above 60 per cent by the end of 2025. And with a cost of $2,750 per kilogram on a reused Falcon 9, this most-flown booster in US history sits head and shoulders above any other launch service provider in the world. Other rockets struggle to compete with SpaceX's proven reusability and high launch cadence. The now-retired Shuttle averaged $54,400/kg, ULA's Atlas V and Vulcan may reach $9,800/ kg and Blue Origin's New Glenn promises launch prices of just $1,500/kg. SpaceX believes its giant Starship vehicle may achieve costs as low as $250–$600/kg when it becomes fully operational. Since first stages and payload fairings constitute 80 per cent of the…

GEMINIDS 2025 The wonderful Geminid meteor shower reaches its peak mid-month, with virtually no Moon to spoil the show HEAD HUNTER Six deep-sky gems to discover above Orion CHASING SHADOWS Track the strange nebula that can't stop flickering About the writers Astronomy expert Pete Lawrence is a skilled astro imager and a presenter on The Sky at Night monthly on BBC Four Steve Tonkin is a binocular observer. Find his tour of the best sights for both eyes on page 54 Also on view this month… ✦ 24P/Schaumasse brightens ✦ Callisto shadow transit ✦ Regulus occulted ✦ 16 Psyche at opposition ✦ Ursid meteor shower Red light friendly To preserve your night vision, this Sky Guide can be read using a red light under dark skies Get the Sky Guide…

BEST TIME TO SEE: As shown Jupiter is heading towards an equinox. This is when the planet's alignment with the Sun is such that the Sun appears to cross its equatorial plane. Earth has two equinoxes every year, one in late March and one in late September. Jupiter's year is a little longer – equivalent to 11.9 Earth years – and so its equinoxes are further apart, occurring approximately every six years. Jupiter's axial tilt is quite small at just 3.1°, but the time around a Jovian equinox is still special, allowing a number of unusual mutual events to occur between its largest moons. In addition, Callisto's orbit appears edge-on enough for the moon and its shadow to start interacting with Jupiter's disc. If you're an avid Jupiter watcher, you'll…

In the world of astronomy, we cherish things that change in appearance, because those changes reveal information. Plotting the light curve of a variable star, for example, tells us a great deal about the star and what causes its variability. Shifts in planetary atmospheres or even on the surface of the Sun offer insights into how these bodies work. The movement of light across the lunar surface reveals how the terrain and its features are ‘constructed’. But when it comes to changing appearances, the deep sky doesn't immediately spring to mind. Yet some deep-sky objects do vary. Obvious examples include galaxies that host supernovae outbursts. But there's an amazing object – well within the range of amateur equipment – that changes for a different reason. Hubble's Variable Nebula (NGC 2261)…

Many of the sights on this Christmas night tour are big enough and bright enough to spot with the naked eye, making them easy – or at least easier! – to track down with your new telescope. But some will be more challenging, and you might not find them all on your first attempt. But that's ok – it's all part of learning how to use your telescope. Every seasoned stargazer you see looking into a complex setup covered in more wires and cables than a nuclear reactor was once a beginner like you. Take your time – you'll get there!…

“In my view, and those of researchers like Fred Hoyle, life permeates the Universe and had its origins early on at the centre of the Galaxy. Fred and I made the case for the existence of complex organic building blocks in comets and interstellar clouds back in the 1970s and ‘80s. We were proved correct. The case for panspermia is building. The ISRO's 2001 balloon experiments collected samples 30–41km (19–25 miles) above the Earth. These showed new strains of bacteria never seen before. The survivability of bacteria and viruses in space, as well as plant seeds and even complex life like tardigrades, has been proven via the recent EXPOSE tests on the ISS. Viruses such as the worldwide 1918–19 flu pandemic may have arrived from space – illnesses from that…

PHOTO OF THE MONTH FREE BONUS CONTENT Find our extended Gallery at www.skyatnightmagazine.com/bonus-content Emission nebula NGC 6164 Cecil Navick and Francis Bozon, captured remotely via Obstech, El Sauce Observatory, Chile, 4 May–28 June 2025 Cecil and Francis say: “We chose NGC 6164 because it's rarely photographed, plus it's a target well suited to our scope's focal length and the camera's highly sensitive sensor.” Equipment: ZWO ASI6200MM camera, PlaneWave CDK14 astrograph, Mathis MI-750 mount Exposure: 118h total Software: PixInsight, Astro Pixel Processor, Photoshop Cecil and Francis's top tips: “For this type of object, we needed long exposures of 600 seconds, with selective filters to bring out the maximum signal. Substantial exposure time is essential; in this case – once we'd sorted through the best images – 118 hours!” The Andromeda Galaxy Jayden…

VITAL STATS Price £279 Optics 130mm parabolic Newtonian Focal length 650mm, f/5 Focuser 1.25-inch rack and pinion Mount German equatorial Extras 20mm and 10mm eyepieces, red dot finder, smartphone adaptor, accessory tray, screwdriver Weight 11.4kg Supplier Optical Vision Limited Tel 01359 244200 www.opticalvision.co.uk Any beginner telescope kit should be easy to use and come complete, with no need for extra purchases. Sky-Watcher's latest addition to its StarQuest line, the DX130P, offers new astronomers exactly that: a novice-friendly all-in-one solution that turned out to be a genuine pleasure to review. Unpacking the boxes, we discovered a smart metallic black optical tube assembly, tubular steel tripod with accessory tray, Sky-Watcher's new StarQuest DX equatorial mount with counterweight and bar, and a box of accessories that included a red dot finder, two eyepieces,…

On a Mission Valerie Neal Smithsonian Books £29 • HB This is an inspiring tribute to the trailblazing women who shaped NASA's human spaceflight programmes. Meticulously researched and thoughtfully written, it charts the evolution of their roles in space exploration, offering both historical insight and personal stories that bring these pioneers to life. Neal sets the stage with a look at the cultural and institutional barriers women faced in entering aviation and spaceflight, highlighting the misconceptions about the female body and psyche that long kept women from consideration. Chapter two introduces us to the ‘firsts’ – those who broke barriers and redefined what was possible. Here we meet Sally Ride, the first American woman in space; Kathy Sullivan, the first American woman to perform a spacewalk; Mae Jemison (pictured), the…

When to use this chart 1 Dec 00:00 AEDT (30 Nov, 13:00 UT) 15 Dec 23:00 AEDT (12:00 UT) 31 Dec 22:00 AEDT (11:00 UT) The chart accurately matches the sky on the dates and times shown for Sydney, Australia. The sky is different at other times as the stars crossing it set four minutes earlier each night. DECEMBER HIGHLIGHTS As comet 24P/Schaumasse nears its January perihelion, it approaches maximum brightness (eighth magnitude) in late December in Coma Berenices, on the Virgo border. It rises in the early hours alongside the new Moon on the 20th. In December's final week, it crosses the Virgo Cluster, forming striking conjunctions with several of its brightest members, such as Markarian's Chain, and passing within 1.5° of M98 (25th), M99 (26th), M100 (27th), M88 (29th) and…

Television Find out what The Sky at Night team have been exploring in recent and past episodes on page 18 Online Visit our website for space news, astrophoto galleries, observing guides and more Social media Follow us on X (Twitter), Facebook and Instagram for the latest astro news Podcasts Stargazing advice plus interviews with top space scientists – all in our monthly Star Diary podcast Tablet/phone Get each month's issue on your Apple or Android device, now with bonus image galleries eNewsletter The best targets to observe each week, delivered to your inbox. Visit bit.ly/skynewsletter Find out more at: www.skyatnightmagazine.com…

If there's one thing you don't want passing through your galaxy, it's a rogue black hole destroying everything in its path. Astronomers believe just such an intruder ploughed through spiral galaxy NGC 3627 in the constellation of Leo – leaving behind a 20,000-lightyear trail of destruction. By analysing images from the JWST and ALMA, researchers found this streak of compressed gas and dust, which looks similar to the contrail left by a jet engine – only 100 billion times bigger. As the trail doesn't follow the galaxy's rotation or curvature, the team suspect it was caused by the fly-by of a massive, compact object with a mass roughly 10 million times that of the Sun. There are only a few objects in the cosmos this massive. If it wasn't a…

On the intersection of Crenshaw Boulevard and Jack Northrop Avenue in Hawthorne, California, stands an unlikely monument – a modern-day obelisk that bears silent witness to a space revolution. Fourteen storeys tall and partially screened by toughened glass, this SpaceX Falcon 9 was the first orbital-class rocket to launch into space and then return to land intact. Ten years ago, it inspired millions. Today, it inspires even more. Its nine Merlin engines gleam in the California sunlight. Four aluminium grid fins, like great mechanised ears, helped guide this behemoth back from space to alight on a Cape Canaveral landing pad. And four extendable landing legs, spanning 18 metres (60ft) from tip to tip, recall the night of 21 December 2015, when it blasted into space, flipped around in mid-flight and…

Tuesday 2 Ganymede's shadow crosses Jupiter's disc between 06:11 and 09:26 UT this morning. The event ends under daylight conditions. Thursday 4 The 98%-lit waxing gibbous Moon occults the Pleiades from around 03:00 UT. Uranus is 4.6° south of the Moon at this time. Today's Moon is full at 23:14 UT, around 12 hours after perigee, making this a perigee full Moon. Monday 8 Saturn's largest moon Titan transits the planet's globe this evening between 17:38 and 23:58 UT. Callisto begins to transit Jupiter's disc between 02:11 and 06:20 UT. Friday 12 Ganymede is eclipsed by Jupiter's shadow from 23:54 UT this evening, reappearing at 05:59 UT on 13 December. Saturday 13 There's an optimum opportunity this evening to spot this month's Moonwatch feature (see page 52), the crater Scheiner. If you're clouded out, there's…

The annual Geminid meteor shower reaches peak activity towards the middle of December. This is a rich shower with a peak zenithal hourly rate (ZHR) of 150 meteors per hour. It's a wonderful one to observe if you have clear, dark skies, as the radiant – close to the star Castor (Alpha (α) Geminorum) – rides high across the December sky. A meteor shower's radiant position is the area of sky from which its meteors appear to emanate. The Geminids are active 4–17 December, but rates are typically fairly low across much of this period. It's only when you get within days of the predicted peak that activity increases significantly. This year's peak is predicted to occur at 08:00 UT on 14 December, meaning you should have a decent chance…

KEY TO STAR CHARTS When to use this chart 1 December at 00:00 UT 15 December at 23:00 UT 31 December at 22:00 UT On other dates, stars will be in slightly different positions because of Earth's orbital motion. Stars that cross the sky will set in the west four minutes earlier each night. How to use this chart Hold the chart so the direction you're facing is at the bottom. The lower half of the chart shows the sky ahead of you. The centre of the chart is the point directly over your head. Sunrise/sunset in December* Moonrise in December* *Times correct for the centre of the UK Lunar phases in December FREE BONUS CONTENT Paul and Pete's night-sky highlights Southern Hemisphere guide www.skyatnightmagazine.com/bonus-content…

Most people can recognise the iconic shape of Orion, formed from seven bright stars, representing the body of a hunter. Once you've picked it out, it's easy to locate Orion's ‘head’, marked by the star Meissa (Lambda (λ) Orionis). This mag. +3.4 star forms the northern point of a small right-angled triangle with mag. +4.4 Phi1 (φ1) and +4.1 Phi2 (φ2) Orionis. The name Meissa comes from the Arabic ‘Al-Maisan’, meaning ‘the Shining One’. A lovely description, but one intended for another star: Alhena (Gamma (γ) Geminorum). The name was mistakenly transferred to Lambda Orionis, an error that persists to the present day. Meissa has a spectral class of O8 III, the O8 indicating that it's a hot blue-white star, and the III indicating that it's a giant. It's estimated…

1. Collinder 69 Orion's head is marked by the star Meissa (Lambda (λ) Orionis). With the naked eye, Meissa is joined by Phi1 (φ1) and Phi2 (φ2) Orionis to form a right-angled triangle around 45 arcminutes wide. A small scope will show many more stars intertwined with the main group, with a distinctive line of three seventh-magnitude stars between Meissa and Phi1. These are all part of the Collinder 69 cluster, also known as the Lambda Orionis Cluster. Larger instruments and OIII or H-beta filters reveal faint nebulosity, identified as Sharpless 2-264, particularly around the brighter stars. □ SEEN IT 2. NGC 2169 NGC 2169 marks the southern right angle in a right-angled triangle formed with mag. +4.4 Nu (ν) and +4.4 Xi (ξ) Orionis. Measuring 7 arcminutes across and…

We humans are always wondering whether we're alone in the Universe. But what if we are one of a long line of species that were around long before our planet even existed? This intriguing idea, that life didn't originate on Earth but arrived from elsewhere in the Galaxy, has always been controversial, but it's one that keeps resurfacing. In fact, it's only gaining credence as we uncover more potential signs of life on other planets. If we do find proof that life exists elsewhere, the question that then arises is: did that life evolve separately on each planet, or did it travel there from an earlier source? And if we can entertain the idea that that could have happened elsewhere, why not on Earth? The ‘panspermia’ theory asserts that the…

VITAL STATS Price £869 Sensor Sony IMX585 Resolution 8MP, 3,856 x 2,180 Exposure range 11ms–900 seconds Extras Narrowband and LRGB filters, 12V power cable and adaptor, USB 3.0 cable, extension tube, screwdriver, filter mounting tweezer, camera bag Size 105mm x 102mm Weight 480g Supplier Rother Valley Optics Tel 01909 774521 www.rothervalleyoptics.co.uk QHY's miniCAM8 has got to be one of the most interesting recent releases on the astrophotography market: a petite, all-in-one imaging solution at an attractive price point. QHY has added a dual-stage thermoelectric cooling fan to Sony's extremely popular IMX585 sensor, plus a suite of well-considered accessories, including an integrated eight-position filter wheel with complete LRGB and Ha, SII and OIII narrowband filter set, cables and adaptors. We anticipate this package could encourage newcomers to our wonderful hobby, as…

1 Omegon red dot finder for DSLR Price £60 • Supplier The Widescreen Centre www.widescreen-centre.co.uk DSLR cameras coupled with long lenses are a great route into astrophotography. This LED finder, with five brightness levels, fits into a DSLR's hot shoe bracket and simplifies the process of finding your targets. 2 Planets sweatshirt Price £44.95 • Supplier VO Clothing www.vo.clothing This unisex sweatshirt is perfect for all astronomers. Made from combed and ringspun cotton, it's manufactured using eco-friendly methods and arrives in plastic-free packaging. Available in navy, green or black, it comes in sizes XS to 2XL. 3 Bresser LER zoom 1.25-inch deluxe 8mm-24mm eyepiece Price £225 • Supplier Bresser UK www.harrisontelescopes.co.uk We love a zoom eyepiece for grab-and-go astronomy! This version features multi-coated lenses and is made from black anodised…

Ben Evans Spaceflight expert “SpaceX and others now stand on the cusp of a revolution, promising to make access to space cheaper, more routine and more frequent than ever before.” Ben examines the rise and rise of reusable rockets on page 35 Jane Green Science journalist “I really enjoyed revisiting the many reasons that stars twinkle. It's always fun to deconstruct and share why they sparkle as they do.” Jane takes us through the science of scintillation on page 40 Stuart Atkinson Seasoned astronomer “Got a new telescope? The night sky over Christmas will be a great gift for new scope owners.” If you're wondering where to point your stargazing present, Stuart has 10 great suggestions on page 60…

I've just read Stuart Atkinson's account of his trials and tribulations whilst trying to capture comet A6 Lemmon (www.skyatnightmagazine.com). I was smiling as I read, because it almost exactly matched my own frustrations. I have been waiting for the comet to brighten enough to image with my Seestar S30 smart scope, and have twice in the last week got excited by clear, blue, daytime skies, only to have my hopes dashed by evening clouds rolling in off the Atlantic. I had all but given up until today. While not cloudless, at least the clouds were separate and fast-moving. I managed to gather nearly 30 minutes of data from our Bortle 2 sky and only had to discard a handful of subs due to passing satellites. All the best and clear…

Universal Time (UT) and British Summer Time (BST) Universal Time (UT) is the standard time used by astronomers around the world. British Summer Time (BST) is one hour ahead of UT RA (Right ascension) and dec. (declination) These coordinates are the night sky's equivalent of longitude and latitude, describing where an object is on the celestial ‘globe’ Family friendly Objects marked with this icon are perfect for showing to children Naked eye Allow 20 minutes for your eyes to become dark-adapted Photo opp Use a CCD, planetary camera or standard DSLR Binoculars 10x50 recommended Small/ medium scope Reflector/SCT under 6 inches, refractor under 4 inches Large scope Reflector/SCT over 6 inches, refractor over 4 inches GETTING STARTED IN ASTRONOMY If you're new to astronomy, you'll find two essential reads on…

Comet 24P/Schaumasse is a brightening comet best seen in the morning sky during December. On the morning of 1 December, find it near the star Algieba (Gamma (γ) Leonis). It then tracks across the body and tail of Leo throughout the month, passing north of Denebola (Beta (β) Leonis) on the night of 18/19 December. A few days after this, it enters the constellation of Coma Berenices on a track that will take it across a rich, deep galaxy field, encountering the likes of M98, M99, M100, M88, M91 and M90. Throughout December, 24P/Schaumasse's integrated magnitude is expected to increase from around mag. +11.5 on 1 December to +10.0 on New Year's Eve. This places it within small-telescope territory and, given clear skies, it's going to be an exciting object…

You may have bought this December issue of BBC Sky at Night Magazine because you've been given – or you've treated yourself to – a new telescope for Christmas. And you may be wondering what to do with it now you've got it. If so, we're here to help! Every stargazer starts here. Even those with Dobsonian telescopes the size of a WW2 battleship cannon or the latest computer-controlled astrophotography rigs once stood where you are now and asked: “So… what do I do next?”. If you haven't got a clue what to look at through your new telescope as darkness falls on Christmas Day, this feature is for you. Think of it as a cosmic selection box of fascinating festive treats, sights that will make you say “Wow!” and…