Taxonomy term

star

Second stars can distort planet size estimates

When light from a star is blocked by another celestial body — as when the moon obstructed light from the much-larger sun during the recent solar eclipse — astronomers can estimate the density of exoplanets that orbit the star. And from the density, they can determine whether a planet is rocky like Earth or gaseous like Jupiter. But a new study in the Astronomical Journal shows that such density assessments, which are normally calculated from the size of the planet, may be skewed by the presence of “hidden” stars.

08 Nov 2017

High-powered simulation tracks evolution of universe in detail

The universe burst into existence 14.6 billion years ago, and has been expanding ever since. Of course, humans have only been around to glimpse the most recent fraction of stellar history. Now, a new high-powered computer simulation called Illustris, which traces more than 13 billion years of cosmological evolution, is giving scientists and the public alike an armchair view of how things came to look the way they do.

26 Sep 2014

Twinkle, twinkle new little star

What’s red, sparkly and far from home? Not Dorothy’s shoes, but a Thorne-Zytkow object (TZO), a type of hybrid star theorized since 1975 to exist but not observed until now.
 

10 Sep 2014

Unprecedented low water-vapor levels detected on exoplanets

In a recent study, a team of astronomers found that the atmospheres of Jupiter-sized planets located outside of the solar system are much drier than predicted. The discovery has raised questions about the commonly held understanding of the processes involved in planet formation.

13 Aug 2014

North star loses mass but still shines bright

The North Star, the Pole Star, the Guiding Star, Polaris: Its many names reflect the many centuries humans have gazed northward to it for guidance. Because Earth’s North Pole is aligned with Polaris’ position in the sky, the star appears motionless, providing a steadfast beacon for early sailors and adventurers alike. But the star itself is far from motionless. In fact, Polaris is a specific type of star known as a Cepheid variable, which pulsates, varying in size and luminosity over a period of days and, according to recent observations, also ejects large amounts of mass into space.

03 May 2012

Scientists find watery super-Earth

The search for Earth-like planets has never looked better. Scientists say they have discovered a water-rich planet that is only 2.7 times larger than Earth. Although positioned just outside the habitable zone for life, the planet gives scientists their best hope yet that other Earth-like planets exist in our universe.

16 Dec 2009

Online stargazing with GigaGalaxy Zoom

Blogging on EARTH

In need of a sense of perspective? The European Southern Observatory has a new way to look at the universe: with a zoom button.

16 Sep 2009