Astronomers have announced that they have discovered what they believe to be .ice cold earth”, a cold but potentially habitable rocky world similar to our own, less than 150 light-years away.
As explained in a recent article, studythis exciting Earth-like exoplanet candidate, named HD-137010 b, may be slightly larger than our planet, about 1.2 times more massive. Its yearly length may also be the same as ours, as it appears to swing around its gentle orange star every 355 days.
The researchers suggest that, judging by its year length, there is a 51% chance that HD-137010 b lies just inside its star’s habitable zone, avoiding the Sun’s boundaries where liquid water could form on its surface.
Plotting known rocky worlds around various stars reveals the rarity of Earth-like planets in the habitable zone (green). The graph on the right plots the incident luminous flux, or the amount of starlight that the planet receives. The stars at the top of each graph are rocky planets in our solar system. (Wenner et al. APJL2026. )
HD-137010 b orbits a star called HD-137010. K dwarf It is about 70 percent the size and mass of the Sun.
This cool, dim dwarf star would live much longer than a G-type star because of its more stingy hydrogen consumption. HD-137010’s lower mass means it has a longer main-sequence lifetime (the period of time it spends fusing hydrogen into helium). longer than the current age of the universe.
Overall, HD-137010 is an intriguingly unique find. “This is the first planetary candidate with Earth-like radius and orbital characteristics to pass through a sun-like star bright enough to allow substantial tracking observations,” the researchers said. say.
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Follow-up observations are needed to confirm the status of HD-137010 b’s planet, but researchers predict that “there is a high possibility that this is a real planet.”
They teased its existence using data from NASA’s now-retired Kepler Space Telescope, astronomy’s first dedicated planetary probe. means of transportation.
The transit method uses observatories like Kepler to “star” at the star and wait for the light to dim as a potential exoplanet passes by or in front of it. The resulting star silhouette causes a dip in the star’s light, which can reveal details of the exoplanet’s radius and orbit.
Astronomers have only witnessed HD-137010 b pass by once. Additionally, confirming exoplanet candidates requires observing multiple passes, so worlds with Earth-like orbits “require several years of observation,” he said.
But there are many reasons to be optimistic.
The discovery of HD-137010 b “demonstrates the detectability of temperate and cold Earth-sized exoplanets orbiting Sun-like stars through a single transit,” the researchers said. explain.
Future observations may have to wait for next-generation observatories such as: ESA Platosuch a world is at the observation limits of today’s facilities.
For now, existing orbital and stellar details suggest that HD-137010 b may be located within its star’s habitable zone. But because Earth receives less than a third of the energy it receives from the Sun, HD-137010 b could be between -68 degrees Celsius and -85 degrees Celsius (-90 degrees Fahrenheit and -121 degrees Fahrenheit), even colder than its famously frigid neighboring red star.
It may be colder than that, but MarsHD-137010 b may still exhibit fortuitous atmospheric conditions that allow for the presence of water on the surface.
Given what researchers know about other Earth-sized exoplanets in the star’s habitable zone, say “It is very plausible that moderate CO will occur.2-A rich atmosphere will encourage the production of liquid surface water. ”
But just as HD-137010 b’s long orbit complicates its confirmation, its Earth-like features come with another caveat. If there is CO2 With abundances similar to Earth’s, HD-137010 b could be trapped in a “snowball” climate.
This scenario would produce a fully glacial planet that is highly reflective, reflecting incoming starlight and reducing its surface temperature to about -100 degrees Celsius.
But HD-137010 b may not be the only one. Although it appears to be isolated, other known exosolar systems suggest otherwise.
Additional planets may exist inside or outside HD-137010’s orbit. In fact, such objects could form a “solar system-like structure” with multiple planets spread throughout the habitable zone and perhaps even more distant Jupiter-sized planets.
Related: Ancient ‘wet lava ball’ exoplanet defies expectations
With so many similarities to our own solar environment, could an “icy cold Earth” support life? Although a frozen world may seem unsuitable for life as we know it, The earth itself was a snowball It has been repeated many times over the course of 4.5 billion years of geological evolution.
This study Astrophysics Journal Letter.