Only one white dwarf star has ever been caught eating an asteroid. Recently, however, astronomers may have found another that just finished its meal.
Eating Asteroids
Although stars like our Sun don’t explode in violent supernovae like their massive counterparts, they don’t slink quietly into a peaceful old age either. When a solar-mass star reaches the end of its main sequence life, it first swells dramatically (the Sun may eventually grow so large that it consumes Earth and the device you’re reading this on), then shrinks down to a tiny but incredibly hot ember known as a white dwarf.
As one might imagine, this process is not kind to any planets or asteroids that were previously circling the star. While some might survive, others are sent spiraling inwards where they break apart and are accreted onto their hosts. Due to the extreme temperatures and surface gravity of white dwarfs, whatever falls on their surfaces is vaporized, sorted by weight, and quickly dragged out of sight. Since heavy elements cannot last long in a white dwarf’s atmosphere, whenever astronomers see their stains in the star’s spectrum, they know that the star must have recently consumed the rocky remains of their former asteroids and planets.
However, although researchers have found these stains in over a quarter of white dwarfs and consequently have reasoned that asteroid snacking must be common, they’ve only ever caught one star mid-meal. Recently, Ben Zuckerman (University of California, Los Angeles) and a team of collaborators may have found another, though it may have just finished dining.
Leftover Crumbs
The light curve of WD J0234-0406 measured by the Zwicky Transient Facility. Unlike WD 1145+017, which frequently changes brightness, this white dwarf appears remarkably steady despite the high-velocity gas surrounding it. [B. Zuckerman et al. 2026]
This new star, called WD J0234-0406, shares some characteristics with the “iconic” WD 1145+017 that was first spotted mid-meal, but it also differs in an interesting way. High-resolution spectroscopy reveals that both stars have gaseous material orbiting around them along highly non-circular paths. These have been interpreted as “precessing rings of high velocity gas” that previously belonged to parent asteroids. However, while WD 1145+017 appears to flicker as bits of disintegrating asteroids pass between it and our line of sight, WD J0234-0406 is rock steady. Neither TESS nor the Zwicky Transient Facility have detected any dips in light from the star despite the evidence that solid material must have recently drizzled into the star’s atmosphere.
The researchers suggest that this relative quiet is a matter of timing. While asteroids are actively breaking up around WD 1145+017, the parent bodies that supplied the gas and dust around WD J0234-0406 may have shattered long ago and have already been either vaporized or ground down into smaller particles. All that is left over are the crumbs slowly spiraling toward the star.
Although WD J0234-0406’s meal may not be as dramatic as WD 1145+017’s feast, it’s still exciting to expand the sample of known white dwarf-asteroid interactions. And, with the upcoming release of data from the DESI survey poised to reveal the spectra of tens of thousands of white dwarfs, the sample is likely to grow again soon.
Citation
“High-velocity Circumstellar Gas Orbiting a White Dwarf Star,” B. Zuckerman et al 2026 ApJ 1004 254. doi:10.3847/1538-4357/ae23c4
In the mid-'90s, the web was exploding, but finding anything of actual value on it felt like an elaborate negotiation with whatever proto-search engine happened to be standing closest to the door. Unlike now, when Google is widely seen as both portal and gatekeeper, sites like AltaVista, Lycos, Excite, HotBot, and Ask Jeeves promised to tame the chaos, each with its own suite of quirks, charms, and flaws.
The real story of pre-Google search is not that early engines were inferior. It's that they reflected a different Internet entirely, one where directories mattered, crawling was still an art, ranking was fragile, and the idea of “search” had not yet hardened into a single dominant interface.
A different kind of web
The first thing to remember about the pre-Google Internet is that there was no built-in assumption that you could search for everything. Many users found pages through Yahoo-style directories, bookmarks, newsgroups, email signatures, and links from site to site because the web was still small enough that human organization could compete with machine indexing. It was an era of Wild West-style discoverability. Search engines existed, but they were only one part of a larger ecosystem that blended curation and accident.
In the mid-'90s, the web was exploding, but finding anything of actual value on it felt like an elaborate negotiation with whatever proto-search engine happened to be standing closest to the door. Unlike now, when Google is widely seen as both portal and gatekeeper, sites like AltaVista, Lycos, Excite, HotBot, and Ask Jeeves promised to tame the chaos, each with its own suite of quirks, charms, and flaws.
The real story of pre-Google search is not that early engines were inferior. It's that they reflected a different Internet entirely, one where directories mattered, crawling was still an art, ranking was fragile, and the idea of “search” had not yet hardened into a single dominant interface.
A different kind of web
The first thing to remember about the pre-Google Internet is that there was no built-in assumption that you could search for everything. Many users found pages through Yahoo-style directories, bookmarks, newsgroups, email signatures, and links from site to site because the web was still small enough that human organization could compete with machine indexing. It was an era of Wild West-style discoverability. Search engines existed, but they were only one part of a larger ecosystem that blended curation and accident.
FaceTime Dual Capture is bringing simultaneous front-and-rear camera streaming to video calls in iOS 27, allowing compatible iPhones to show the caller and their surroundings without repeatedly switching between cameras.
The feature expands technology Apple introduced with the iPhone 17 family. Dual Capture already allows the Camera app to record through the Center Stage front camera and a rear camera at the same time. iOS 27 brings a similar capability directly into live FaceTime calls.
During a call, the front camera can continue showing the speaker while the rear camera displays whatever the iPhone is pointing toward. Someone attending a concert can share the performance and remain visible. A parent can show a child playing without disappearing from the conversation. A person asking for technical assistance can remain on screen while directing the rear camera toward the equipment causing the problem.
Dual Capture removes the awkward sequence of switching to the rear camera, showing something, and switching back to continue speaking face to face. Both perspectives remain available inside the same call.
Image Credit: Thomas Trutschel Photothek/Getty Images
FaceTime Dual Capture Changes Camera Switching
The normal FaceTime camera control changes from a simple front-or-rear choice on supported iPhones. When the caller activates the rear camera, iOS 27 keeps the front camera visible by default.
The main view displays the rear camera feed while a smaller window contains the front camera image. This picture-in-picture arrangement gives the other participant a continuous view of the caller’s reaction, commentary, or explanation.
To activate both cameras during a supported FaceTime call:
FaceTime > Start a video call > Tap the Flip button
Tapping the Flip button turns on the rear camera without immediately removing the front view. The other participant begins receiving both perspectives as part of the FaceTime stream.
The caller can disable the front view when it is no longer needed. This provides a conventional rear-camera presentation for situations where the surroundings should occupy the complete image.
To return to a single camera view:
FaceTime > Tap the camera view > Disable the front camera
The exact labels and placement may change before the public release of iOS 27 because the feature is still being tested in beta software. Its basic behavior is already established: the Flip control activates the rear camera while retaining the front camera feed.
Dual Capture does not create two independent FaceTime calls. Both images belong to one video stream, so the caller does not need a second account, device, or invitation.
The feature also differs from screen sharing. FaceTime screen sharing transmits applications and interface activity from the iPhone display. Dual Capture transmits live video from two physical cameras.
Image Source: Google
Which iPhones Support Dual Capture
Apple has limited FaceTime Dual Capture transmission to the iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air. Each model includes Apple’s 18MP Center Stage front camera and the Dual Capture capability introduced in the Camera app.
An older iPhone that supports iOS 27 cannot originate a Dual Capture stream. It continues to use the normal option of selecting either the front camera or a rear camera during a call.
Older models can still receive and display a Dual Capture feed when they are running iOS 27. This allows an iPhone 16 or another supported device to see both views transmitted from an iPhone 17, even though it cannot send the same presentation back.
Both participants need iOS 27 for the new FaceTime layout to work as intended. The transmitting device must also be one of the supported iPhone 17-generation models.
This limitation is based on Apple’s official feature support rather than the simple presence of front and rear cameras. Earlier iPhones have camera hardware capable of operating in several multi-camera applications, but Apple has not extended its native Dual Capture implementation to them.
Third-party applications have offered forms of simultaneous multi-camera recording for years through Apple’s developer frameworks. The difference is that iOS 27 integrates the experience into FaceTime, where users can activate it through the familiar camera-switching control.
iPhone 17 Owners Receive a Second Dual Capture Feature
Describing FaceTime Dual Capture as retro-compatible with the iPhone 17 does not fully explain its relationship with the hardware. The iPhone 17 family introduced Apple’s native Dual Capture recording in 2025, and iOS 27 now gives that existing camera system another purpose.
Inside the Camera app, Dual Capture produces a saved video containing front and rear views. Apple lists support for recording at up to 4K Dolby Vision at 30 frames per second on the iPhone 17.
FaceTime uses the camera pairing for live communication instead. Network quality, bandwidth, device temperature, and FaceTime processing can affect the transmitted resolution, so users should not assume that a call will preserve the Camera app’s maximum 4K recording specification.
The Center Stage front camera also contributes more than resolution. Its square sensor gives the iPhone greater freedom to adjust framing without requiring the device to be physically rotated. Center Stage can help keep the caller positioned inside the smaller front-camera view while the rear camera follows the subject being shared.
That combination makes Dual Capture more useful than placing two untreated camera feeds beside each other. FaceTime can preserve the speaker’s presence while directing most of the screen toward the event, object, or location being discussed.
The feature may require more processing power and energy than an ordinary single-camera call. Running two camera sensors while encoding and transmitting live video can increase battery consumption and device temperature, especially during long calls over cellular data.
Apple has not published separate battery estimates for Dual Capture FaceTime calls. Users planning extended sessions may want access to power and a stable Wi-Fi connection.
iOS 27 Prepares FaceTime for iPhone 18
FaceTime Dual Capture arrives shortly before Apple’s expected iPhone 18 generation, making it likely to become part of how the company demonstrates the new phones’ camera and communication abilities.
Apple has not announced the iPhone 18 lineup or confirmed its final camera specifications. Compatibility with FaceTime Dual Capture is therefore expected from the software’s “iPhone 17 and newer” positioning, but individual iPhone 18 models should not be treated as confirmed until Apple presents them.
The software release gives existing iPhone 17 owners access without requiring another hardware purchase. That approach also provides Apple with a working FaceTime feature before the next iPhone launch rather than introducing the camera mode and communication interface at the same moment.
Future hardware could improve the experience through faster processors, stronger image stabilization, upgraded sensors, or more efficient video encoding. None of those additions is required for the supported iPhone 17 family, which already contains the camera system needed to transmit both views.
Dual Capture is only one part of the FaceTime update. Apple is also improving video-call quality when the network connection is weak, addressing a problem that becomes especially relevant when two live camera views require transmission. Traditional Chinese support is joining FaceTime Live Captions as well.
The weak-connection improvement may determine how dependable Dual Capture becomes away from Wi-Fi. A feature designed for travel, events, repairs, and outdoor calls needs to tolerate changes in cellular bandwidth without freezing both views or forcing the session to end.
FaceTime Dual Capture remains part of the iOS 27 beta as Apple prepares the public update for September. Apple can still adjust the interface, performance, device requirements, and picture-in-picture behavior before the completed software reaches iPhone 17 owners.
Even the darkest corners of the universe are not completely empty. A recent study has used fast radio bursts to provide the first estimate of the baryon content in cosmic voids.
What’s in a Void?
Cosmological studies have revealed the large-scale filamentary structure of the universe known as the cosmic web. Chains of galaxies and galaxy clusters fall into spindly strands (or filaments) of matter overdensities, opening up cavernous cosmic voids that comprise the darkest corners of the universe. These seemingly vacant voids serve as critical test beds for cosmology, allowing researchers to constrain things like the nature of dark energy and the matter density of the universe.
Despite their name, voids are not completely empty but are instead underdensities with considerably less matter compared to the bustling filaments they border. The baryon (normal matter) content of cosmic voids has important implications for cosmological models and large-scale galactic feedback processes, but assessing how many baryons actually occupy voids has only recently become observationally accessible.
Sky maps centered on the north celestial pole showing the CHIME fast radio burst sample (top) and the SDSS void catalog (bottom). [Sharma et al 2026]
Fast radio bursts — brief, intense flashes of radio waves emitted by compact objects — have proven to be versatile tools for measuring both underdensities and overdensities throughout the universe. The dispersion measure of fast radio bursts, which tells us how many free electrons fall between the radio emitter and observer, can be directly used to map the baryon content along the lines of sight. Fast radio burst sight lines passing through overdensities will produce a dispersion measure excess, and those passing through underdensities will produce a dispersion measure deficit relative to the cosmic mean. Thus far, fast radio bursts have been used extensively to study overdense galaxy and cluster filaments, but their sensitivity to underdense regions like voids has yet to be explored.
Chiming In on the Baryon Search
In concept, directly stacking fast radio burst sight lines that coincide with the positions of known cosmic voids provides a direct measurement of the baryon underdensity inside voids. With no previous observational exploration of this quantity, Kritti Sharma (California Institute of Technology) and collaborators leveraged the second catalog of the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Bursts (CHIME/FRB) sample in conjunction with the Sloan Digital Sky Survey (SDSS) Baryon Oscillation Spectroscopic Survey (BOSS) void catalog to provide the first observational assessment of the baryon underdensity in cosmic voids.
Anticorrelations between fast radio burst dispersion measures and void positions. There is a clear dispersion measure deficit closer to voids centers. [Sharma et al 2026]
Stacking thousands of fast radio burst sight lines that spatially align with thousands of known voids, the authors measured a statistically significant dispersion measure deficit toward void centers. This deficit indicates that, as theory predicts, baryons inhabit cosmic voids at a suppressed level. The team used cosmological models to quantify the electron density contrast between the interior and exterior of voids, finding an approximate baryon underdensity of 60% ± 30% relative to the cosmic mean. Combining this result with existing thermal scattering measurements of the cosmic microwave background, the authors estimated a mean void gas temperature of about 1.1 million kelvin — voids are occupied by a suppressed amount of warm-hot diffuse gas.
This study provides a unique approach to baryon mapping and opens up the door for future investigation of cosmic voids. While not physically containing much, voids hold vast astrophysical and cosmological significance. With the astronomical stage primed with galaxy-mapping powerhouses like the Dark Energy Spectroscopic Instrument, Vera Rubin Observatory, Nancy Grace Roman Space Telescope, and Euclid Space Telescope, cosmic voids will become a cornerstone of cosmological studies.
Citation
“Baryons in the Darkest Sites of the Universe,” Kritti Sharma et al 2026 ApJL 1006 L3. doi:10.3847/2041-8213/ae81ac
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