Category Astronomy/Space

In this image, north is up. The southern portion of the left inset above shows the cratered plateau uplands informally named Vega Terra (note that all feature names are informal). A jagged scarp, or wall of cliffs, known as Piri Rupes borders the young, nearly crater-free plains of Piri Planitia. The cliffs break up into isolated mesas in several places. Credit: Image courtesy of NASA

Far in the western hemisphere, scientists on NASA’s New Horizons mission have discovered what looks like a giant “bite mark” on Pluto’s surface. They suspect it may be caused by a process known as sublimation – transition of a substance from a solid to a gas. The methane ice-rich surface on Pluto may be sublimating away into the atmosphere, exposing a layer of water-ice underneath.

Cutting diagonally across t...

An illustration of the binary black hole system in OJ287. The predictions of the model are verified by observations. Credit: Gary Poyner, UK

An international team using several optical telescopes and NASA’s SWIFT X-ray telescope. The rotational rate of this massive black hole is 1/3 of the maximum spin rate allowed in General Relativity. This 18 billion solar mass heavy black hole powers a quasar OJ287 which lies about 3.5 billion light years away from Earth. This quasar lies very close to the apparent path of the Sun’s motion on the celestial sphere as seen from Earth, where most searches for asteroids and comets are conducted. Therefore, its optical photometric measurements already cover more than 100 years...

60 percent of them have corresponding optical/infrared galaxies, whereas the remaining 40 percent are invisible in other wavelength. Credit: ALMA (ESO/NAOJ/NRAO), NAOJ, Fujimoto et al.

A research team using ALMA has detected the faintest millimeter-wave source ever observed. By accumulating millimeter-waves from faint objects like this throughout the Universe, the team finally determined that such objects are 100% responsible for the enigmatic infrared background light filling the Universe. By comparing these to optical and infrared images, the team found that 60% of them are faint galaxies, whereas the rest have no corresponding objects in optical/infrared wavelengths and their nature is still unknown.

The Universe looks dark in the parts between stars and galaxies...

Complete control of light waves would allow the miniaturization of traditional optical components, such as lenses, polarizers or beam-splitters, to nanoscale sizes while dramatically increasing their performance and resolution. Credit: Copyright Agency for Science, Technology and Research (A*STAR)

This may lead to new light-based technologies. Complete control of some of the key properties of light waves – polarisation and phase – at the nanoscale is of major interest for light-based technologies such as display screens, and in energy harvesting and data transmission. It would allow, for example, the miniaturization of traditional optical components, such as lenses, polarizers or beam-splitters, to nanoscale sizes...