-
Posts
-
By hellowalkman · Posted
This could exactly be how our Sun but it's not as simple by Sayan Sen Image by Drew Rae via Pexels An international team led by Université de Montréal (University of Montreal) PhD student Érika Le Bourdais has found that the ancient white dwarf star LSPM J0207+3331 is still pulling in planetary debris, even though it has been cooling for about three billion years. White dwarfs are dense, Earth-sized stellar remnants left behind when Sun-like stars exhaust their nuclear fuel and shed their outer layers. The star, located 145 light-years away in the constellation Triangulum, is the oldest and coldest white dwarf known to have a surrounding disk of dust. The star was first spotted in 2019 by a citizen scientist through the Backyard Worlds: Planet 9 project. Its cool temperature immediately suggested that it was very old, since white dwarfs gradually lose heat over time. Using the W. M. Keck telescopes in Hawaii, astronomers later confirmed that the star shows infrared signals consistent with dust rings formed by asteroids breaking apart under its strong gravity. Such infrared excesses occur when a star emits more infrared light than expected, often because warm dust surrounding it absorbs and re-radiates energy. “This discovery challenges our understanding of planetary system evolution,” said Le Bourdais. “The fact that we still see planetary debris being accreted three billion years after the star became a white dwarf suggests that asteroids, comets, and even planets can remain in orbit around these stars for a very long time.” Spectroscopic analysis—a technique that studies light to identify the chemical elements present in an object—revealed thirteen heavy elements in the star’s atmosphere: sodium, magnesium, aluminium, silicon, calcium, titanium, chromium, manganese, iron, cobalt, nickel, copper, and strontium. Normally, heavy elements sink quickly in hydrogen-rich white dwarfs, making them hard to detect. “We expected to see only a few elements, but we found dozens!” explained Le Bourdais. The research paper adds more detail. The absence of carbon features suggests the debris came from a carbon-volatile-depleted source. The abundance pattern shows slight deficits of magnesium and silicon compared to iron but otherwise resembles Earth-like material. This points to a differentiated rocky body—one whose materials have separated into distinct layers such as a metallic core and rocky mantle—with a metallic core fraction higher than Earth’s. In other words, the star is accreting the remains of a large rocky object, similar in structure to Earth or the asteroid Vesta. “White dwarfs offer one of the only ways we can directly measure the composition of exoplanets,” said Patrick Dufour, co-author and professor at Université de Montréal. “When planetary debris come too close, they are torn apart by the star’s gravity and end up polluting its atmosphere, leaving a detailed chemical fingerprint of its composition.” The team also detected weak Ca II H & K line core emission, making this only the second known isolated polluted white dwarf to show this feature. These are specific spectral signatures produced by ionised calcium and can indicate unusual physical activity in a star’s upper atmosphere. The finding suggests that extra physical processes may be happening in or above the star’s upper atmosphere. The study stresses the importance of including heavy elements in model atmosphere calculations, since leaving them out can distort the inferred structure and lead to inaccurate stellar parameters. Earlier work suggested the star’s infrared excess came from two dust rings. The new analysis shows that a single silicate dust disk—a ring composed largely of rock-forming minerals rich in silicon and oxygen—can explain the observed signal at 11.6 μm, simplifying the picture of the system’s structure. The question of how debris ended up falling into the star so late remains open. One idea is that giant planets in the system slowly destabilised smaller bodies over billions of years. Another possibility is that a passing star disturbed the orbits of debris. “Future observations with the James Webb Space Telescope or archival data found in the European Space Agency’s Gaia mission could help distinguish between a planetary rearrangement and the gravitational effect of a close stellar encounter,” said John Debes, co-author and researcher at the Space Telescope Science Institute. Dufour noted that hydrogen-rich white dwarfs are the most common type, and the coolest among them are the oldest stars in the galaxy. “We didn't have the habit of looking for signs of accretion in them. This unique case motivates us to expand our search to more of these stars.” The findings show that even after billions of years, planetary systems can remain active and complex. Substantial accretion events—the gradual accumulation of surrounding material onto a celestial object—can still occur long after a star’s death, offering a rare window into the composition and fate of distant worlds. Source: University of Montreal, IOPScience This article was generated with some help from AI and reviewed by an editor. Under Section 107 of the Copyright Act 1976, this material is used for the purpose of news reporting. Fair use is a use permitted by copyright statute that might otherwise be infringing. -
-
By +Edouard · Posted
Given the hefty price tag this thing will likely have I doubt many everyday home users will be in the market for one especially given the current climate. -
By Copernic · Posted
ESET 19.1.14 by Razvan Serea NOD32 for Windows is the best choice for protection of your personal computer. Almost 20 years of technological development enabled ESET to create state-of-the-art antivirus system able to protect you from all sorts of Internet threats. ESET Internet Security boasts a large array of security features, usability enhancements and scanning technology improvements in defense of your your online life. ESET Internet Security ESET Internet Security keeps your computer or laptop safe with intelligent multi-layered protection combining proven antivirus, antispyware, firewall, anti-rootkit and antispam capabilities. Based on ESET NOD32 Antivirus, it protects you from viruses, worms, spyware, and all Internet threats. It conserves resources and improves computer speed. You are protected at the highest level while you work, social network, play online games or plug in removable media. ESET NOD32 Antivirus Your best defense against viruses, trojans and other forms of malware—and the top choice for IT professionals. Powered by the ThreatSense® engine with advanced heuristics, which blocks far more unknown threats than the competition. The latest generation of the legendary ESET NOD32 Antivirus takes your security to a whole new level. Built for a low footprint, fast scanning, it packs security features and customization options for consistent and personalized security online or off. ESET Smart Security Ultimate protection for everyday web users, thanks to ESET’s trademark best balance of detection, speed and usability. Stay safe from viruses and spyware. Stay protected from ransomware - Blocks malware that tries to lock you out of your own data. Receive free support by email or telephone in your local language, wherever you are. Bank and shop online more safely - automatically secures transactions on internet banking sites, and helps to protect you on online payment gateways. Stop hackers from accessing your PC - Personal Firewall prevents hackers from gaining access to your computer and keeps you invisible when you use public Wi-Fi. Keep your kids safe online - block unwanted internet content by categories or individual websites and keep your kids safe online with Parental Control. Safer webcam and home router - Get an alert when anyone tries to access your webcam, and check your home router for vulnerabilities. Safely store passwords, and encrypt your data. Safely store, generate and prefill your passwords, and encrypt your files and removable media (USB keys). Includes protection for smartphones and tablets. Protect all of your devices - mix and match security protection for up to 3 or 5 devices. ESET Security Ultimate ESET Security Ultimate offers all-in-one protection with antivirus, anti-malware, and anti-phishing features. It includes a personal firewall, secure online banking, and a password manager for enhanced security. Parental controls and data encryption keep family and sensitive information safe. It also provides regular updates to ensure you're always protected against the latest threats. It's user-friendly and ensures comprehensive digital security, perfect for those seeking reliable protection without complexity. ESET 19.1.14.0 changelog: Fixed: GUI crahes Fixed: IPM issues Download: ESET NOD32 Antivirus 64-bit | NOD32 Antivirus 32-bit | ARM 64 | ~ 80.0 MB (Free Trial) Download: ESET Internet Security 64-bit | ESET Internet Security 32-bit Download: Eset Smart Security Premium 64-bit | Eset Smart Security Premium 32-bit Download: ESET Security Ultimate 64-bit | ESET Security Ultimate 32-bit ARM64: Antivirus | Internet Security | Smart Security | ESET Security Ultimate Link: ESET Home Page Get alerted to all of our Software updates on Twitter at @NeowinSoftware -
By o0o.paw · Posted
+1 for Rufus. I bought NTLite a few years ago to scrape all the bloat out of Windows 11. It is not a perfect solution as there is a steep learning curve if you don't really know what you are doing (me included). I have finally got a Windows install that just works. I only keep things I use and nothing else.
-
-
Popular Contributors
-
Tell a friend
.thumb.png.b7089ebbdf00d96b3b92dddbd04bac02.png)
.thumb.jpg.97db76d73f0f840ec31db7c170de109d.jpg)
Recommended Posts