Astronomers have found plenty of white dwarf stars surrounded by debris disks. Those disks are the remains of planets destroyed by the star as it evolved. But they’ve found one intact Jupiter-mass planet orbiting a white dwarf.
Are there more white dwarf planets? Can terrestrial, Earth-like planets exist around white dwarfs?
According to new research we can start writing the eulogy for four exoplanets around a Sun-like star about 57 light years away. But there’s no hurry; we have about one billion years before the star becomes a red giant and starts to destroy them.
The Fomalhaut system is nearby in astronomical terms, and it’s also one of the brightest stars in the night sky. That means astronomers have studied it intensely over the years. Now that we have the powerful James Webb Space Telescope the observations have intensified.
The Fomalhaut system has a confounding and complex dusty disk, including a dusty blob. The blob has been the subject of an ongoing debate in astronomy. Can the JWST see through its complexity and find answers to the systems unanswered questions?
With thousands of known exoplanets and tens of thousands likely to be discovered in the coming decades, it could be only a matter of time before we discover a planet with life. The trick is proving it. So far the focus has been on observing the atmospheric composition of exoplanets, looking for molecular biosignatures that would indicate the presence of life. But this can be difficult since many of the molecules produced by life on Earth could also be produced by geologic processes. A new study argues that a better approach would be to compare the atmospheric composition of a potentially habitable world with those of other planets in the star system.
Most of the planets in the Universe orbit a star. They are part of a system of planets, similar to our own solar system. But a few planets drift alone in the cosmos. For whatever reason, be it a near collision or slow gravitational perturbations that destabilize its orbit, these planets are cast out of their star system and sent adrift. These rogue planets are notoriously challenging to find, but as we start to discover them we’re finding they are a bit more common than we’d thought. Now a new study posits a reason why.
When the JWST activated its penetrating infrared eyes in July 2022, it faced a massive wish-list of targets compiled by an eager international astronomy community. Distant, early galaxies, nascent planets forming in dusty disks, and the end of the Universe’s dark ages and its first light were on the list. But exoplanets were also on the list, and there were thousands of them beckoning to be studied.
But one distant solar system stood out: HR 8799, a system about 133 light-years away.
Despite the fact that we’ve discovered thousands of them, exoplanets are hard to find. And some types are harder to find than others. Naturally, some of the hardest ones to find are the ones we most want to find. What can we do?
Keep working on it, and that’s what a trio of Chinese scientists are doing.
As planet-hunting scientists find more and more planets, they’ve encountered some puzzles. One of them concerns the lack of Neptune-size worlds orbiting close to their stars. Astronomers think that these planets aren’t massive enough to retain their atmospheres in the face of their stars’ powerful radiation, which strips it away.
But at least one of these planets has retained its atmosphere. How?
Earth is our only example of a habitable planet, so it makes sense to search for Earth-size worlds when we’re hunting for potentially-habitable exoplanets. When astronomers found seven of them orbiting a red dwarf star in the TRAPPIST-1 system, people wondered if Earth-size planets are more common around red dwarfs than Sun-like stars.
A recent study published in The Astrophysical Journal Letters used data obtained by the James Webb Space Telescope’s (JWST) Mid-Infrared Instrument (MIRI) to identify the presence of quartz nanocrystals in the upper atmosphere of WASP-17 b, an exoplanet whose mass and radius are approximately 0.78 and 1.87 that of Jupiter, respectively, and is located approximately 1,324 light-years from Earth. WASP-17 b is classified as a “puffy” hot Jupiter due to its 3.7-day orbital period, meaning the extreme temperatures could cause unique chemical processes to occur within its atmosphere, but the astronomers were still surprised by the findings.