Category Astronomy/Space

Artist’s concept of the spacecraft. Credit: FMI

A fleet of tiny spacecraft could visit over 300 asteroids in just over 3 years, according to a mission study led by the Finnish Meteorological Institute. The Asteroid Touring Nanosat Fleet concept comprises 50 spacecraft propelled by innovative electric solar wind sails (E-sails) and equipped with instruments to take images and collect spectroscopic data on the composition of the asteroids. Each nanosat would visit 6 or 7 asteroids before returning to Earth to deliver the data. The concept will be presented by Dr Pekka Janhunen at the European Planetary Science Congress (EPSC) 2017 in Riga on Tuesday 19th September.

“Asteroids are very diverse and, to date, we’ve only seen a small number at close range...

NGC 7674, seen just above the center, is a luminous spiral galaxy with a powerful active nucleus. Credit: NASA, ESA, the Hubble Heritage Team

A study using multiple radio telescopes confirms that supermassive black holes found in the centers of galaxies can form gravitationally bound pairs when galaxies merge. “The dual black hole we found has the smallest separation of any so far detected through direct imaging,” said David Merritt, professor of physics at Rochester Institute of Technology The supermassive black holes are located in the spiral galaxy NGC 7674, ~400 million light years from earth, and are separated by a distance less than one light year...

The dotted white arrow points to curved strata recording point bar growth and river migration. The boundaries of ancient valley walls are defined by textural and albedo changes and are also associated with lateral river migration. Stacked above the point bars and completely confined within the dotted white and black lines are topographically inverted river deposits outcropping as ridges (e.g., black arrow). In places (e.g., south of the dotted white arrow), the ridges run against the dotted boundaries, suggesting flow was once redirected along a valley wall. Credit: B.T. Cardenas et al., Geological Society of America Bulletin

River deposits exist across the surface of Mars and record a surface environment from over 3.5 billion years ago that was able to support liquid water at the surface...

Sampling of a dust devil during field campaign ‘Morocco 2016’. The samples are still under analysis. Credit: Jan Raack/Dennis Reiss

Swirling columns of sand and dust, known as dust devils, are a feature of desert areas on Mars and on Earth. Now, a study of terrestrial dust devils has shown that around 2/3 of the fine particles lifted by these vortices can remain suspended in the atmosphere and be transported around the globe. The findings have implications for the climate and weather of both planets and, potentially, human health here on Earth.

The study by Raack and an international team of collaborators gives important insights into the contribution of dust devils to mineral aerosols in planetary atmospheres...