The discovery of over 4000 planets (4,171 confirmed and counting!) beyond our Solar System has revolutionized the field of astronomy. Unfortunately, one of the downsides of all these discoveries is how it has shaken up theories about how our Solar System formed. In the past, astronomers thought that the eight planets (or nine, or over one hundred, depending on your point of view) formed where they are currently located.
However, the discovery of gas giants that orbit close to their stars (aka. “Hot Jupiters”) has confounded this thinking. But according to a recent NASA-supported study, the recent discovery of a young gas giant could offer clues as to how Jupiter-like planets form and whether or not they migrate. This discovery was made possible thanks to the Spitzer Space Telescope, which continues to reveal things about our Universe even in retirement.
Continue reading “Do Hot Jupiters Form Close in, or Do They Migrate? A Newly-Discovered Planet Might Help Answer This”
Six billion Earth-like planets in the Milky Way? If true, that’s astounding. But the number needs some context.
The Milky Way has up 400 billion stars. So even if there are six billion Earth-like planets, they’re still spread far and wide throughout our vast galaxy.
Continue reading “Astronomers Estimate There Are 6 Billion Earth-Like Planets in the Milky Way”
NASA’s TESS, or Transiting Exoplanet Survey Satellite has one main job: finding exoplanets. But it’s also helping astronomers study a strange type of star that has so far defied thorough explanation. Those stars are Delta Scuti stars, named after their prototype.
Continue reading “TESS is Also Helping Astronomers Study Bizarre Pulsating Stars”
In the 17th century, astronomers witnessed many stellar events that proved that the starry sky was not “fixed and eternal.” This included stars whose brightness varied over time – aka. “variable stars.” By the 20th century, many variable stars had been cataloged and astronomers have discerned subclasses of them as well – notably, stars that swell and shrink, known as pulsating variables.
In all cases, these variable stars were found to have rhythmic pulsations that were visible from all sides. But a recent discovery by an international team has confirmed that there are variable stars that can pulse from only one side. This pulsating star, part of a system known as HD 74423, is located about 1,500 light-years from Earth and is the first of its kind to be found.
Researchers working with data from NASA’s TESS (Transiting Exoplanet Survey Satellite) have a found a planet that orbits two stars. Initially, the system was identified by citizen scientists as a pair of eclipsing binary stars without a planet. But an intern taking a closer look at that data found that it was misidentified.
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NASA’s TESS (Transiting Exoplanet Survey Satellite) has found its first Earth-sized planet located in the habitable zone of its host star. The find was confirmed with the Spitzer Space Telescope. This planet is one of only a few Earth-sized worlds ever found in a habitable zone.
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TESS, the Transiting Exoplanet Survey Satellite, has imaged an outburst from the comet 46P/Wirtanen. It caught the outburst in what NASA is calling the clearest images yet of a comet outburst from start to finish. A comet outburst is a significant but temporary increase in the comet’s activity, outside of the normal sunlight-driven vaporization of ices that creates a comet’s coma and tail.
Astronomers aren’t certain what causes them, but a new study based on this observation is shedding some light on them.
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Like many other spiral galaxies in the Universe, the Milky Way Galaxy consists of two disk-like structures – the thin disk and the thick disk. The thick disk, which envelopes the thin disk, contains about 20% of the Milky Way’s stars and is thought to be the older of the pair based on the composition of its stars (which have greater metallicity) and its puffier nature.
However, in a recent study, a team of 38 scientists led by researchers from Australia’s ARC Centre of Excellence for All Sky Astrophysics in Three Dimensions (ASTRO-3D) used data from the now-retired Kepler mission to measure starquakes in the Milky Way’s disk. From this, they have revised the official estimates on the age of the Milky Way’s thick disk, which they conclude is around 10 billion years old.
Continue reading “A New Way to Measure the Age of the Milky Way”
On April 18th, 2018, NASA’s Transitting Exoplanet Survey Satellite (TESS) took to space for the first time. By August, it began capturing the light curves of distant stars for signs of planetary transits, effectively picking up where the Kepler Space Telescope left off. Now, just a few months away from the end of its primary mission, NASA has put a year’s worth of images of the southern sky together to create the beautiful mosaic you see here.
Continue reading “TESS Has Now Captured Almost the Entire Southern Sky. Here’s a Mosaic Made of 15,347 Photographs”
Astronomers working with TESS (Transiting Exoplanet Survey Satellite) data have found a planet where it shouldn’t be: in the space recently filled by its host star when it was a red giant.
Continue reading “It Seems Impossible, But Somehow This Planet Survived its Star’s Red Giant Phase”