Search Results for “planetary migration”

Mars and Earth may not have always been neighbours

21 December 2017 Astronomy Now

A study published in the journal Earth and Planetary Science Letters posits that Mars formed in what today is the Asteroid Belt, roughly one and a half times as far from the Sun as its current position, before migrating to its present location.

Kepler-223 star system has four mini-Neptunes in synchronised orbits

12 May 2016 Astronomy Now

A four-planet system orbiting the star Kepler-223 in the constellation Cygnus is actually a rarity: Its planets, all miniature Neptunes nestled close to the star, are orbiting in a unique resonance that has been locked in for billions of years. For every three orbits of the outermost planet, the second orbits four times, the third six times and the innermost eight times.

Massive exoplanet in hellish 18-hour orbit faces tidal destruction

24 February 2020 Astronomy Now

A massive exoplanet is found in an 18-hour orbit around its host star, one of the shortest-period exoplanets discovered to date.

Possible exomoon signal found

29 July 2017 Keith Cooper

Strong hints have been found of a possible exomoon candidate orbiting a gas giant planet over 4,000 light years away in the constellation of Cygnus the Swan. Should the moon be confirmed later this year by the Hubble Space Telescope, it will be the first moon ever discovered around a planet beyond our Solar System.

Astronomers capture best view ever of disintegrating comet

16 September 2016 Astronomy Now

The sharpest, most detailed observations of a comet breaking apart have been captured with the NASA/ESA Hubble Space Telescope. The images suggest that the roughly 4.5-billion-year-old comet, named 332P/Ikeya-Murakami, may be spinning so fast that material is ejected from its surface. The resulting debris is now scattered along a 3,000-mile-long trail.

Warm Jupiters are not as lonely as expected

15 July 2016 Astronomy Now

After analysing four years of observations from NASA’s Kepler space telescope, astronomers from the University of Toronto have given us our clearest understanding yet of a class of exoplanets called “warm Jupiters,” showing that many have unexpected planetary companions.

Newborn giant exoplanet found orbiting close to its parent star

20 June 2016 Astronomy Now

A team of astronomers has confirmed the existence of a young planet known as K2-33b, only 11 million years old, that orbits very close to its star (at 0.05 astronomical units), with an orbital period of 5.4 days. Approximately five times the size of the Earth, the new planet is a “super-Neptune” and the youngest such planet known.

Understanding stellar adolescence through T-Tauri stars

13 June 2016 Astronomy Now

A newborn star typically goes through four stages of adolescence. It begins life as a protostar, accreting material and developing a proto-planetary disc. Slowly, stellar winds and radiation blow away the surrounding shell of gas and dust. Next, when the surrounding envelope has cleared, is called the T-Tauri phase. Finally, accretion stops and the source’s radiation comes from the star’s photosphere.

A highly eccentric “hot Jupiter” exoplanet

29 March 2016 Astronomy Now

Astronomers have observed the extreme temperature variations of HD 80606 b, a Jupiter-sized exoplanet with a highly eccentric, comet-like orbit that brings it scorchingly close to its parent star every 111 days. The researchers also calculated the planet’s rotation rate — the first exoplanet rotation rate ever obtained.

‘Cannibalism’ between stars

5 February 2016 Astronomy Now

Stars are born inside a rotating cloud of interstellar gas and dust. Before finding itself on the star, however, most of the cloud lands onto a circumstellar disc forming around the star. The manner in which the material is transported through the disc onto the star, causing the star to grow in mass, has recently become a major research topic in astrophysics.