In this era of exoplanet discovery, astronomers have found over 5,000 confirmed exoplanets, with thousands more awaiting confirmation and many billions more waiting to be discovered. These exoplanets exist in a bewildering spectrum of sizes, compositions, orbital periods, and just about every other characteristic that can be measured.
Learning about them has also shed light on our Solar System. We used to think of it as an archetypal arrangement of planets since it’s all we had to go on. But now we know we might be the outlier because we have no Super-Earth.
We have it relatively easy on the Earth. Our Sun is relatively calm. The space weather environment in the solar system is altogether placid. Things are nice. But new research has shown that we may be the exception rather than the rule, and that many exoplanets face much harsher conditions than we do.
Tragically sometimes stars engulf their own planets. While most stars are able to quickly cover up the evidence for their crime, a new study by astronomers has revealed that in some cases the evidence can linger for up to two billion years.
Although we have found thousands of exoplanets in recent years, we really only have three methods of finding them. The first is to observe a star dimming slightly as a planet passes in front of it (transit method). The second is to measure the wobble of a star as an orbiting planet gives it a gravitational tug (Doppler method). The third is to observe the exoplanet directly. Now a new study in the Astrophysical Journal Letters has a fourth method.
In our solar system, we have two types of planets. Small, warm, rocky worlds populate the inner region, while the outer region has cold gas giants. Intuitively this makes a lot of sense. When the solar system was forming, the Sun’s light and heat must have pushed much of the gas toward the outer system, leaving heavier dust and rock to form the inner worlds. Giants could only grow in the cold, dark outer solar system. But we now know our solar system is more the exception than the rule. Many star systems have large gas planets that orbit close to their stars. These hot Jupiters and hot Neptunes are unlike anything in our solar system, and astronomers are keen to understand what they may be like.
In this age of exoplanet discovery, we’ve discovered thousands of exoplanets of different types. The hot Jupiter is one of the most unusual types. There’s nothing like it in our Solar System.
Hot Jupiters are massive gas planets, and they attract a lot of attention because they’re so close to their stars and reach blistering temperatures. Their existence spawns a lot of questions about their formation and evolution. A new study is trying to answer some of those questions by determining hot Jupiters’ ages.
NASA’s Kepler planet-hunting spacecraft was deactivated in November 2018, about ten years after it launched. The mission detected over 5,000 candidate exoplanets and 2,662 confirmed exoplanets using the transit method. But scientists are still working with all of Kepler’s data, hoping to uncover more planets in the observations.
A team of researchers have announced the discovery of one more planet in the Kepler data, and this one is nearly a twin of Jupiter.
Hubble’s most remarkable feature might be its longevity. The Hubble has been operating for almost 32 years and has fed us a consistent diet of science—and eye candy—during that time. For 13 of its 32 years, it’s been checking in on a protoplanet forming in a young solar system about 530 light-years away.
Planet formation is always a messy process. But in this case, the planet’s formation is an “intense and violent process,” according to the authors of a new study.