Category Astronomy/Space

Artist’s concept shows the gaseous exoplanet CoRoT-2b with a westward hot spot in orbit around its host star. Credit: NASA/JPL-Caltech/T. Pyle (IPAC)

Puzzling finding raises new questions about atmospheric physics of giant planets. The hottest point on a gaseous planet near a distant star isn’t where astrophysicists expected it to be – a discovery that challenges scientists’ understanding of the many planets of this type found in solar systems outside our own. Unlike our familiar planet Jupiter, hot Jupiters circle astonishingly close to their host star – so close that it typically takes fewer than three days to complete an orbit. And one hemisphere of these planets always faces its host star, while the other faces permanently out into the dark.

Not surprisingly, the “day” side of the pl...

Artistic rendition of strong winds disrupting the outer disc of material surrounding a stellar-mass black hole. The disk material (mostly in yellow) is first pulled from the outer parts of a nearby star (upper right-hand). The stellar-mass black hole sits at the center of the approximately 5 million kilometer disc, but it only consumes the material if and when it reaches the central 30 kilometers. Credit: NASA/Swift/A. Simonnet, Sonoma State University 

New research shows the first evidence of strong winds around black holes throughout bright outburst events when a black hole rapidly consumes mass. The study, published in Nature, sheds new light on how mass transfers to black holes and how black holes can affect the environment around them...

A precise measurement of the magnetic field in the corona of the black hole binary V404 Cygni. Science, 2017; 358 (6368): 1299 http://science.sciencemag.org/content/358/6368/1299

Chris Packham, associate professor of physics and astronomy at The University of Texas at San Antonio (UTSA), has collaborated on a new study that expands the scientific community’s understanding of black holes in our galaxy and the magnetic fields that surround them. Packham and astronomers observed the magnetic field of a black hole within our own galaxy from multiple wavelengths for the first time.

Black holes usually form when a massive star explodes and the remnant core collapses under the force of intense gravity...

NASA and MIT scientists analyzed subtle changes in Mercury’s motion to learn about the Sun and how its dynamics influence the planet’s orbit. The position of Mercury over time was determined from radio tracking data obtained while NASA’s MESSENGER mission was active. Credit: NASA’s Goddard Space Flight Center

Like the waistband of a couch potato in midlife, the orbits of planets in our solar system are expanding. It happens because the Sun’s gravitational grip gradually weakens as our star ages and loses mass. Now, a team of NASA and MIT scientists has indirectly measured this mass loss and other solar parameters by looking at changes in Mercury’s orbit.

The new values improve upon earlier predictions by reducing the amount of uncertainty...