ALMA tagged posts

Illustration of the dust ring surrounding HD 181327. Credit: Amanda Smith, University of Cambridge

Astronomers have found evidence of ice and comets orbiting a nearby sun-like star, which could give a glimpse into how our own solar system developed. Using Atacama Large Millimeter Array (ALMA), the researchers, led by the University of Cambridge, detected very low levels of CO around the star, in amounts that are consistent with the comets in our own solar system. The results are a first step in establishing the properties of comet clouds around sun-like stars just after the time of their birth.

Comets are essentially ‘dirty snowballs’ of ice and rock, sometimes with a tail of dust and evaporating ice trailing behind them, and are formed early in the development of stellar systems...

ALMA image of the planet-forming disk around the young, Sun-like star TW Hydrae. The inset image (upper right) zooms in on the gap nearest to the star, which is at the same distance as the Earth is from the Sun, suggesting an infant version of our home planet could be emerging from the dust and gas. The additional concentric light and dark features represent other planet-forming regions farther out in the disk. Credit: S. Andrews (Harvard-Smithsonian CfA), ALMA (ESO/NAOJ/NRAO)

New images reveal never-before-seen details in the planet-forming disk around a nearby Sun-like star, including a tantalizing gap at the same distance from the star as the Earth is from the Sun. The disks of dust and gas that surround young stars are the formation sites of planets...

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...