The Daily Galaxy --Great Discoveries Channel: Sci, Space, Tech

Supermassive Black Holes Created by Colliding Galaxies --New Discovery

Collisions between two galaxies may explain why supermassive black holes form develop in them, according to a new research by an international team headed by Dr John Silverman of the University of Kashiwa, Japan. These supermassive black holes are usually found in the most massive galaxies, and that their size is proportional to the "bulge" in the center of the galaxy -- that is the mass of the stars in the middle.

Image of the Day: Jupiter's Io --Volcanic Hotpsot of the Solar System

Recent analysis of data from NASA's Galileo spacecraft reveals a subsurface ocean of molten or partially molten magma beneath the surface of Jupiter's volcanic moon Io. The finding is the first direct confirmation of this kind of magma layer at Io and explains why the moon is the most volcanic object known in the Solar System. The research was conducted by scientists at the University of California, Los Angeles; the University of California, Santa Cruz;, and the University of Michigan, Ann Arbor.

"Scientists are excited we finally understand where Io's magma is coming from and have an explanation for some of the mysterious signatures we saw in some of the Galileo's magnetic field data," said Krishan Khurana, lead author of the study and former co-investigator on Galileo's magnetometer team at UCLA. "It turns out Io was continually giving off a 'sounding signal' in Jupiter's rotating magnetic field that matched what would be expected from molten or partially molten rocks deep beneath the surface."

"Search for Earth's Twin" --Is the End of the Kepler Mission Imminent?

Is the USA walking away from a mission that hopes to answer one the the truly great questions of the 21st Century: Are we alone in the Universe?

According to widespread rumor, word has leaked out that the Obama administration intends to terminate NASA’s planetary exploration program. The Mars Science Lab Curiosity, being readied on the pad, will be launched, as will the nearly completed small MAVEN orbiter scheduled for 2013, but that the now-orbiting Kepler Telescope will be turned off in midmission, stopping it before it can complete its goal of finding potential twin Earths.

EcoAlert: Ocean Circluation Found Impacting Greenhouse Gases

 New research from the University of Missouri indicates that Atlantic Ocean temperatures during the greenhouse climate of the Late Cretaceous Epoch were influenced by circulation in the deep ocean. These changes in circulation patterns 70 million years ago could help scientists understand the consequences of modern increases in greenhouse gases.

Is Saturn's Enceladus Emerging as the Solar System's Habitable Hotspot?

Enceladus-flyby-browse Saturn's icy moon Enceladus is emerging as the most habitable spot beyond Earth in the Solar System for life as we know it, scientists said last week at a meeting of the Enceladus Focus Group at the SETI Institute in Mountain View, California.

"It has liquid water, organic carbon, nitrogen [in the form of ammonia], and an energy source," says Chris McKay, an astrobiologist at NASA's Ames Research Center in Moffett Field, California. Besides Earth, he says, "there is no other environment in the Solar System where we can make all those claims."

Milky Way's Newly Discovered Spiral Arm --Will it Prove to Host a Habitable Zone?

A large new spiral arm of the Milky Way peppered with dense concentrations of molecular gas has been discovered by two Harvard astronmers. What are the odds that this new arm might host an Earth-like planet capable of evolving advanced form of life?

Enigmatic Radio-Waves Near Milky-Way's Central Region May Hold Clues to Enduring Mystery

Twenty years ago, astronomers discovered a number of enigmatic radio-emitting filaments concentrated near the center of the Milky Way Galaxy. These features initially defied explanation, but a new study of radio images of the Galactic center may point to their possible source. These mysterious "filaments" of radio-wave emission may hold the ultimate proof of the existence of dark matter, researchers have said. A recent report suggests the filaments' emission arises from dark matter particles crashing into each other.

Image of the Day: Source of a Mysterious Outburst from the Edge of the Milky Way

This image of the variable star V838 Monocerotis near the edge of our Milky Way Galaxy, about 20,000 light-years from our sun, was recorded by the Hubble Space Telescope in September 2006.

The picture spans about 14 light-years. Ever since a sudden outburst was detected in January 2002, this enigmatic star has fascinated astronomers, who expect the expanding echoes to continue to light up the dusty environs of V838 Mon for at least the rest of the current decade. Researchers have now found that V838 Mon is likely a young binary star, but the cause of its extraordinary outburst remains a mystery.

V838 Monocerotis did not expel its outer layers. Instead, it grew enormously in size. Its surface temperature dropped to temperatures that were not much hotter than a light bulb. This behavior of ballooning to an enormous size, but not losing its outer layers, is very unusual and completely unlike an ordinary nova explosion.

Gigantic Loop of Black Holes and Neutron Stars

Arp 147 contains the remnant of a spiral galaxy (right) that collided with the elliptical galaxy on the left. This collision has produced an expanding wave of star formation that shows up as a blue ring containing in abundance of massive young stars. These stars race through their evolution in a few million years or less and explode as supernovas, leaving behind neutron stars and black holes.

Unusual Hollow Discovered on Mercury

NASA's MESSENGER spacecraft has discovered strange hollows on the surface of Mercury. Images taken from orbit reveal thousands of peculiar depressions at a variety of longitudes and latitudes, ranging in size from 60 feet to over a mile across and 60 to 120 feet deep. No one knows how they got there.

"These hollows were a major surprise," says David Blewett, science team member from the Johns Hopkins University Applied Physics Laboratory. "We've been thinking of Mercury as a relic – a place that's really not changing much anymore, except by impact cratering. But the hollows appear to be younger than the craters in which they are found, and that means Mercury's surface is still evolving in a surprising way."

Mars Reconnaissance Orbiter spotted similar depressions in the carbon dioxide ice at Mars' south pole, giving that surface a "swiss cheese" appearance. But on Mercury they're found in rock and often have bright interiors and halos.

"We've never seen anything quite like this on a rocky surface."

If you could stand in one of these "sleepy" hollows on Mercury's surface, you'd find yourself, like Ichabod Crane, in a quiet, still, haunting place, with a black sky above your head.
"There's essentially no atmosphere on Mercury," explains Blewett. "And with no atmosphere, wind doesn't blow and rain doesn't fall. So the hollows weren't carved by wind or water. Other forces must be at work."

As the planet closest to the Sun, Mercury is exposed to fierce heat and extreme space weather. Blewett believes these factors play a role.

A key clue, he says, is that many of the hollows are associated with central mounds or mountains inside Mercury's impact craters. These so-called “peak rings” are thought to be made of material forced up from the depths by the impact that formed the crater. Excavated material could be unstable when it finds itself suddenly exposed at Mercury's surface.