In 1839, the president of Harvard University invited William Bond to move into a house on campus and, by virtue of bringing along his own astronomical equipment, become the universityโs first astronomer in residence. With public interest spurred by the 1835 passage of Halleyโs Comet and the Comet of 1843, Harvard soon had enough moneyContinue reading "July 16, 1850: Bond and Whipple photograph Vega"
Astronomers have spotted four dead star white dwarf stars playing a game of cosmic hide-and-seek, all four of which were hiding in the glares of red dwarf companion stars.
This marks the first detection of white dwarfs existing in double star systems in our cosmic backyard. The white dwarfsare all located within around 65 light-years of Earth, and one of them is number nine in the top 10 closest white dwarfs to the solar system.
White dwarfs are the type of stellar remnants left behind when stars around the size of the sun run out of fuel needed for nuclear fusion. This leads to their cores collapsing. The lack of fusion also means these stellar remnants cool and become dim. Thus, the light of much larger and brighter red dwarf stars is incredibly effective at hiding white dwarfs.
"Nearby isolated white dwarfs are usually easy to find, but we couldn't see these four stars directly in visible wavelengths because their red dwarf companions were drowning out their light," team leader Mairi O'Brien of the University of Warwick in the UK said in a statement."It's a reminder that even in our own cosmic neighborhood, we can still find surprises if we look in the right way, at the right wavelengths."
Wobbles gave them away
Though astronomers have been diligently surveying our cosmic backyard for decades, white dwarfs are extremely good at remaining unseen. In fact, the only thing that gave these four hidden dead stars away? Curious "wobbles" caused in the motion of the stars they were hiding behind, like a hiding child causing a curtain to ripple.
The team followed up on these telltale clues by taking a closer look at these systems with NASA's long-serving Hubble Space Telescope. This investigation was conducted in ultraviolet light and using custom calibration to prevent flaring from the red dwarf companions from mimicking white dwarf signals.
This investigation not only revealed the four lurking white dwarfs, but also demonstrated that one of these systems, G 203-47, located just 25 light-years away, has some curious characteristics. Twenty-seven years elapsed between the initial radial wobble and the detection of this hidden dead star.
That isn't the weird thing, though. What is strange is that the red dwarf companion of this white dwarf only rotates once every 100 Earth days or so, yet it only takes about 15 days to orbit its dead star companion. This means that gravitational forces have failed to lock the red dwarf and white dwarf together, which is what happens in similar systems.
"What's fascinating is that G 203-47 shouldn't be rotating this slowly if it formed the same way as similar systems. This suggests that these binaries have had very different evolutionary histories," team member David Wilson, of the University of Colorado Boulder, said. "Some underwent violent, prolonged interactions early on that locked them tidally. Others, like G 203-47, experienced gentler, briefer encounters that left them in this unusual state."
An illustration of a red dwarf star orbiting a white dwarf dead star companion. (Image credit: Robert Lea (created with Canva))
The discovery of these white dwarfs helps researchers better understand the population numbers of the dead stars throughout the Milky Way. In fact, predictions would have suggested finding roughly four to five closely orbiting white dwarf-red dwarf pairs within around 65 light-years of our solar system, so finding four should instill a lot of confidence in our current theoretical models.
"Only about 30% of red dwarfs within 20 parsecs[65 light-years] have been systematically surveyed for hidden white dwarf companions," team member and University of Warwick researcher Pier-Emmanuel Tremblay said in the statement. "We think there could be as many as nine or 10 additional binary systemsin our local stellar environment that we havenโt found yet.
"If we put more targeted effort into observing red dwarfs, perhaps we will find more surprises like this."
Astronomers have, for the first time, directly mapped the magnetic field surrounding an unusual "lighthouse" pulsar, revealing an invisible cosmic highway that channels particles blasted from the rapidly spinning stellar remnant.
Using NASA's Imaging X-ray Polarimetry Explorer (IXPE) mission, researchers measured the magnetic field around the pulsar PSR J1101โ6101 โ nicknamed the "Lighthouse" โ and confirmed a long-standing prediction that its high-energy particles stream along magnetic field lines extending through the Milky Way. This discovery offers a rare look at how some of the universe's most extreme objects accelerate particles to nearly the speed of light, according to a statement from the space agency.
Pulsars are rapidly rotating neutron stars โ the ultra-dense remnants left behind when massive stars explode as supernovas. Their powerful magnetic fields channel beams of radiation from their magnetic poles that sweep across space as the stars spin, much like the beam of a lighthouse.
PSR J1101โ6101, which is located at the center of the Lighthouse Nebula, spins about 16 times every second and is traveling at supersonic speeds after receiving a powerful kick from the supernova that created it. As it tears through interstellar gas, it leaves behind a bright X-ray tail while producing a narrow filament that juts out almost perpendicular to its direction of travel. Astronomers had long suspected this unusual structure traced energetic electrons escaping along the Milky Way's magnetic field.
"We wanted to test that theory,"Jack Dinsmore, lead author of the study and undergraduate student at Stanford University, said in the statement. "The 'smoking gun' would come by measuring the polarization of the light, which indicates the magnetic field direction. If the magnetic field points along the filament, that confirms that the filament's particles are flowing along the field."
Unlike conventional X-ray telescopes, IXPE measures the polarization of X-rays โ the preferred orientation of their electric fields โ allowing scientists to reconstruct the geometry of otherwise invisible magnetic fields. Because the Lighthouse Nebula is relatively faint in X-rays, the researchers developed new analysis techniques to extract as much information as possible from the observations.
Using IXPE, astronomers measured the nebula's magnetic field for the first time, confirming that high-energy particles escape the pulsar by traveling along the Milky Way's magnetic field lines. (Image credit: X-ray: Chandra: NASA/CXC/Stanford Univ./J.T. Dinsmore et al.; IXPE: NASA/MSFC/J.T. Dinsmore et al., Radio: CSIRO/ATNF/ATCA; Optical: 2MASS/UMass/IPAC-Caltech/NASA/NSF; Image processing: NASA/CXC/SAO/L. Frattare)
The team found that the magnetic field runs parallel to a remarkably long filament extending away from the pulsar, confirming that high-energy particles are streaming along magnetic field lines. But the observations also uncovered an unexpected twist: the field is far more orderly than scientists anticipated. The unusually strong polarization signal suggests the filament contains much less magnetic turbulence than current models predict, offering new insight into how fast-moving pulsars inject energetic particles into the surrounding galaxy.
"The striking divergence in magnetic field orientations observed between radio and X-ray wavelengths provides compelling evidence for the highly structured nature of these objects," Niccolรฒ Bucciantini, co-author of the study from the Italian National Institute for Astrophysics, said in the statement. "This marks the first clear indication that particles of different energies occupy distinct regions within the system, hinting at the presence of multiple, and potentially very different, acceleration mechanisms at work."
Their findings were published July 9 in The Astrophysical Journal.
The universe is haunted by "cosmic ghosts" called neutrinos, and new research suggests they may be the "whispers" of stars that died in supernova explosions over the course of billions of years.
The discovery is an important step forward in our understanding of the life and death of stars and how they enrich their environments with metals, elements heavier than hydrogen and helium. It could also help better understand how black holes and neutron stars are born when massive stars die.
The second most common particles in the universe, neutrinos get their spooky nickname because they are chargeless and near-massless, so phantom-like that around 100 trillion neutrinos pass through you at nearly the speed of light every second, but over your entire life only one will interact with the atoms of your body, if you're lucky.
The newly suggested connection between neutrinos and a history of supernova blasts has emerged from the first detection of a flux of neutrinos called the Diffuse Supernova Neutrino Background (DSNB). It was detected by one of the world's largest neutrino detectors, the Super-Kamiokande, located 3,280 feet (1,000 meters) underground in Gifu Prefecture, Japan.
"Observing the world's first indication of the Diffuse Supernova Neutrino Background is a deeply meaningful achievement and has been a long-cherished goal since the beginning of the Super-Kamiokande project," Hiroyuki Sekiya of the University of Tokyo said in a statement.
Stars go out with a bang but continue with a whisper
Supernovas come in a range of types, but the ones this research concerns are so-called "core-collapse supernovas." These occur when stars much more massive than the sun reach the end of nucleosynthesis in their cores. When they are no longer able to fuse elements to create metals heavier than iron, the stars become unable to produce the outward energy that for millions of years has balanced them against the inward push of gravity.
Thus, with gravity the ultimate winner of this cosmic tug of war, the star's core collapses, sending violent shockwaves rippling outward into the outer stellar layers, which are ripped away. This leaves the core as a stellar remnant, either a neutron star or a black hole, initially surrounded by an expanding shell of supernova debris.
The energy from these events is carried away by particles of light (photons) spread across the electromagnetic spectrum, but also by neutrinos. Yet, despite the fact that supernovas have been erupting every second over the course of 13 billion years or so to produce the neutrinos that accumulate as the DSNB, this ghostly signal is still faint, a whisper rather than a shout.
The Crab Nebula as seen by the Hubble Space Telescope and ground-based telescopes in a composite view The nebula is the aftermath of a core-collapse supernova. (Image credit: NASA, ESA, NRAO/AUI/NSF and G. Dubner (University of Buenos Aires))
To "hear" these cosmic whispers, the team behind this research analysed almost 14 years of data from Super-Kamiokande in the form of Cherenkov light generated when neutrinos interact with 50,000 tons of ultrapure water.
This revealed a signal of neutrinos in line with what would be expected from the DSNB. This signal still needs to be confirmed, but it is a strong indicator of the DSNB, the first humanity has ever had.
Across the universe, supernova explosions occur several times per second. Since the birth of the universe, neutrinos emitted by these supernovae have diffused through space and accumulated over cosmic time. (Image credit: Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo)
"We are already planning on incorporating ongoing observations at Super-Kamiokande together with its successor detector, Hyper-Kamiokande, to further improve sensitivity in future collaborative studies," said team member Yosuke Ashida,of Tohoku University.
The team's results were presented on June 25, 2026, at Neutrino 2026: XXXII International Conference on Neutrino Physics and Astrophysics, held at the University of California, Irvine, USA.
The only three measurables in galactic astronomy are the position, luminosity and spectrum of the source light received in our telescopes. There is no distance information without unprovable assumptions, hence no direct measurement of size or age of the universe. Thus we may conclude it is young in agreement with the Bible.