Space and astronomy news
In 1936 astronomers watched as FU Orionis, a dim star in the Orion constellation, brightened dramatically. The star’s brightness increased by a factor of 100 in a matter of months. When it peaked, it was 100 times more luminous than our Sun.
Astronomers had never observed a young star brightening like this.
Continue reading “The Hubble and FU Orionis: a New Look at an Old Mystery”
Like a performer preparing for their big finale, a distant star is shedding its outer layers and preparing to explode as a supernova.
Astronomers have been observing the huge star, named WOH G64, since its discovery in the 1970s. It’s one of the largest known stars, and also one of the most luminous and massive red supergiants (RSGs). The star is surrounded by an envelope of expelled star-stuff, which could indicate it’s getting ready to explode.
Continue reading “The First Close-Up Picture of Star Outside the Milky Way”
Some binary stars are unusual. They contain a main sequence star like our Sun, while the other is a “dead” white dwarf star that left fusion behind and emanates only residual heat. When the main sequence star ages into a red giant, the two stars share a common envelope.
This common envelope phase is a big mystery in astrophysics, and to understand what’s happening, astronomers are building a catalogue of main sequence-white dwarf binaries.
Continue reading “Main Sequence and White Dwarf Binaries are Hiding in Plain Sight”
In recent years, astronomers have developed techniques to measure the metal content of stars with extreme accuracy. With that capability, astronomers have examined sibling stars to see how their metallicity differs. Some of these co-natal stars have pronounced differences in their metallicity.
New research shows that stars engulfing rocky planets are responsible.
Continue reading “Up to a Third of Stars Ate Some of their Planets”
When we think of exoplanets that may be able to support life, we hone in on the habitable zone. A habitable zone is a region around a star where planets receive enough stellar energy to have liquid surface water. It’s a somewhat crude but helpful first step when examining thousands of exoplanets.
However, there’s a lot more to habitability than that.
Continue reading “Habitable Worlds are Found in Safe Places”
TESS, the Transiting Exoplanet Survey Satellite has been on the lookout for alien worlds since 2018. It has just hit the news again having identified an extreme triple star system where two stars orbit each other every 1.8 days. The third component circles them both in 25 days – this puts the entire system within the orbit of Mercury with a little wriggle room to spare! To visual observers, it looks like a single star but the power of TESS revealed a flicker as the stars line up and pass one another along our line of sight. Eventually, the two inner stars will merge, triggering a supernova event!
Continue reading “TESS Finds a Triple Star System that Could Fit within Mercury’s Orbit”
Photosynthesis changed Earth in powerful ways. When photosynthetic organisms appeared, it led to the Great Oxygenation Event. That allowed multicellular life to evolve and resulted in the ozone layer. Life could venture onto land, protected from the Sun’s intense ultraviolet radiation.
But Earth’s photosynthetic organisms evolved under the Sun’s specific illumination. How would plants do under other stars?
Continue reading “Plants Would Still Grow Well Under Alien Skies”
Astronomers have solid evidence for the existence of stellar-mass black holes and supermassive black holes. However, evidence for Intermediate Black Holes (IMBHs) is more elusive. Their existence remains hypothetical.
However, study by study, evidence is accumulating for IMBHs. The latest comes from the globular cluster M15, where a fast-moving star suggests the presence of something massive. Could it be an elusive IMBH?
Continue reading “A Star Was Kicked Out of a Globular Cluster by an Intermediate-Mass Black Hole”
Although stars are enormous, they’re extremely far away, and appear as point sources in telescopes. Usually, you never get to see more than a pixel. Now astronomers have used the Atacama Large Millimeter/submillimeter Array (ALMA) to resolve details on the surface of the star R Doradus and track its activity for 30 days. The images revealed giant, hot bubbles of gas 75 times larger than the entire Sun. R Doradus is 350 times larger than our Sun, but only 180 light-years away.
“This is the first time the bubbling surface of a real star can be shown in such a way,“ said Wouter Vlemmings, a professor at Chalmers University of Technology in Sweden, and lead author of the study, in a press release from the European Southern Observatory (ESO). “We had never expected the data to be of such high quality that we could see so many details of the convection on the stellar surface.”
Continue reading “High Resolution Images Show Bubbling Gas on the Surface of Another Star”
Humanity’s been fortunate to have a star situated over Earth’s north pole. The star, known as Polaris, or the North Star, has guided many sailors safely to port. But Polaris is a fascinating star in its own right, not just because of its serendipitous position.
Continue reading “Polaris, Earth’s North Star, Has A Surprisingly Spotted Surface”