TL;DR
Prime made for students and young adults
- Fast, free delivery for dorm and study essentials
- Prime Video and Amazon Music included
- Member-only deals
Astronomers reanalyzed archival Hubble data and found a high abundance of niobium in material around white dwarf HS 0209+0832, a clue they say is consistent with a planet formed from material expelled by the dying star. FUSE observations and TESS brightness variations support the interpretation, but the planet remains a candidate and its formation and future are not settled.
Astronomers say a niobium signature in archival Hubble data may point to a second-generation planet around the white dwarf HS 0209+0832. The study, published Monday in Nature Astronomy, proposes that the candidate gas giant formed from material expelled as its parent star died; the evidence supports that interpretation but does not establish the planet’s existence beyond doubt.
When Hubble observed HS 0209+0832 in 1999, its spectrum contained about 100 unidentified chemical features. Jamie Williams, the study’s lead author and a doctoral candidate at the University of Warwick, revisited the archive using an updated chemical database. He found that niobium matched many of the previously unexplained features. The team reports an unusually high abundance of the element in the system.
The researchers checked the Hubble result against observations from NASA’s retired Far Ultraviolet Spectroscopic Explorer mission, which also showed strong niobium signatures. Separately, NASA’s TESS satellite monitored the white dwarf for four months and recorded repeating changes in brightness. The team interprets those variations as evidence of an orbiting object about 3.7 million miles, or 6 million kilometers, from the star.
Based on the available observations, the team estimates that the candidate is a gas giant about Jupiter’s size and is rapidly losing atmosphere. The white dwarf is still hot, and the researchers propose that its energy is stripping material from the planet. That escaping matter could create a disk around the star and fall onto its surface, where Hubble could detect the chemical elements. This is the team’s explanation for the niobium signal, rather than a directly observed account of the planet forming or losing mass.
A Possible Planet After a Star’s Death
If confirmed, the candidate would offer evidence that planet formation can occur after a star has shed its outer layers, using material released during its death. The planets in our solar system formed from material left over when the Sun was born. A second-generation world would represent a different route: the team proposes that chemically enriched debris around a stellar remnant gathered into a new planet.
The proposed object is also in an extreme setting. At an estimated 6 million kilometers from its white dwarf, it orbits much closer than Mercury does to the Sun, and the star’s remaining heat may be eroding its atmosphere. Studying this system could help researchers test how planets behave around stellar remnants and whether such worlds can persist as their stars cool. The reported observations do not yet establish how common these planets are or whether this candidate will follow the long-term path proposed by the researchers.
Products Worth Considering
Shark Navigator Robot Vacuum with 30-Day Self-Emptying Base, White (AV2110S)
Sonos Era 100 SL Compact Microphone-Free Speaker, White
Philips Hue Secure Wired Video Doorbell, 2K, Black
As an affiliate, we earn on qualifying purchases.
How the Hubble Clue Was Found
A white dwarf is the compact remnant core left after a low-mass star has used its nuclear fuel and expelled its outer envelope. In the scenario described by the research team, some of that expelled material could collect into a disk and eventually form a planet. That would make the planet “second-generation”; Earth and the other planets in our solar system are first-generation worlds, formed from material remaining after the Sun’s birth.
The key clue came from reexamining old data rather than from a new Hubble observation. The unidentified features in the 1999 Hubble spectrum became more interpretable after Williams compared them with an updated database. The niobium match prompted the team to investigate further. Co-author Boris Gaensicke said that niobium had not been reported in other white dwarfs analyzed by the researchers, and that recognizing it helped the team make sense of the observations.
Niobium is one of the elements heavier than iron. The study’s co-author Nicholas Stone said such heavy elements are not produced in the cores of stars through ordinary thermonuclear fusion. He described their presence as a sign of the unusual conditions inside dying stars and of material expelled into space. In this system, the researchers link the niobium in material falling onto the white dwarf to the proposed planet and its possible atmosphere loss.
““Rather than the white dwarf stage being a kind of epilogue to the story of a star and its planets, this research points to the systems we are familiar with only being the first chapter of a potentially much longer tale, with some new characters showing up.””
— Jamie Williams, lead author and doctoral candidate at the University of Warwick
The Candidate Still Needs Confirmation
The researchers describe a possible planet, not a confirmed one. TESS recorded periodic brightness variations, which the team interprets as indicating an orbiting object; the observations described in the report do not by themselves settle the object’s nature. The reported evidence also does not directly show a planet forming from the star’s ejecta. That origin is the team’s explanation for the chemistry and orbital evidence.
Several details remain open: how second-generation planets form, how often they occur, and how they evolve around white dwarfs. The team also estimates that the candidate is losing atmosphere, but the source material does not provide a measured rate of loss or a timeline for how long the process may continue. Williams’s suggestion that the planet may survive as the star cools is a researcher’s expectation, not a settled outcome.
More White Dwarf Systems to Study
Williams plans to use Hubble over the next several years to investigate these systems and build observations that can help researchers assess how common second-generation planets may be and how they develop. Further data could test whether the niobium-rich material, brightness variations and proposed planet-loss process fit together as the team suggests.
For now, the study adds a candidate to a still poorly understood class of possible worlds. Follow-up observations and comparisons with other white dwarfs will be needed to clarify the object’s nature, the proposed formation process and the candidate’s longer-term evolution.
Key Questions
Has Hubble confirmed a planet around HS 0209+0832?
No. The study reports evidence consistent with a planet, including niobium in archival Hubble data and periodic brightness variations seen by TESS. The researchers describe the object as a candidate.
What does “second-generation planet” mean?
It means a planet that forms from material expelled by a star as it dies, rather than from the material left over when the star was born. The team proposes this process for the candidate around white dwarf HS 0209+0832.
Why is niobium relevant to the study?
The researchers found that niobium matched many previously unidentified features in Hubble’s 1999 spectrum. They say the element can signal material produced in the unusual conditions of a dying star and expelled into space.
What do researchers estimate about the candidate?
The team estimates that it is a Jupiter-size gas giant orbiting about 6 million kilometers from the white dwarf and rapidly losing atmosphere. These are estimates and interpretations reported by the study, not a complete direct measurement of the planet’s properties.
Source: primary
