Hi there welcomeSid said:
What is particularly interesting about this star is that it was discovered in transit, and because it was only the size of Saturn they incorrectly classified it as an exoplanet. They also recently estimated the minimum mass for a star at 6.7% of Sol, or 70.2 solar masses assuming the same solar metallicity. However, the 6.7% of Sol is theoretical, whereas EBLM J0555-57Ab is observational.Sid said:
Those numbers seem inconsistent with each other, perhaps it's a typo. I'm more familiar with the numbers found in the Wiki on Main Sequence stars: "The lower limit for sustained proton–proton nuclear fusion is about 0.08 M☉ or 80 times the mass of Jupiter.[30]" So the 0.08 is right, but not the 13 times, making this star about the smallest mass you can have and still be a main sequence star.DrSteve said:
The minimum mass required for a star to form is about 0.08 times the mass of our Sun, or 80 times the mass of Jupiter. This is known as the hydrogen-burning limit, where a star is able to sustain nuclear fusion in its core.
No, an object with a mass lower than the minimum cannot form a star. Objects with masses lower than 0.08 solar masses are unable to generate enough heat and pressure in their cores to sustain nuclear fusion, which is necessary for a star to form.
Objects with masses lower than the minimum for star formation are typically classified as brown dwarfs. They are not massive enough to become stars, but are still much larger than planets. Brown dwarfs emit very little light and heat, making them difficult to detect.
Yes, there are stars with masses close to the minimum of 0.08 solar masses. These are known as red dwarfs and are the most common type of star in the universe. They are smaller and cooler than our Sun, but can still sustain nuclear fusion in their cores.
Yes, there is an upper limit for star mass. It is estimated that the maximum mass for a star is around 150 solar masses. Stars with masses higher than this are unable to maintain stability and often explode in a supernova. However, the exact upper limit is still a topic of research and debate among scientists.