Heavens

Constellation Eridanus and a cold spot in the cosmic microwave background

In 2004, astronomers examining a map of the radiation leftover from the Big Bang (the cosmic microwave background, or CMB) discovered the Cold Spot, a larger-than-expected unusually cold area of the sky. The physics surrounding the Big Bang theory predicts warmer and cooler spots of various sizes in the infant universe, but a spot this large and this cold was unexpected.

How to date the moon-forming impact event with meteorites

Through a combination of data analysis and numerical modeling work, researchers have found a record of the ancient Moon-forming giant impact observable in stony meteorites. Their work will appear in the April 2015 issue of the Journal Science. The work was done by NASA Solar System Exploration Research Virtual Institute (SSERVI) researchers led by Principal Investigator Bill Bottke of the Institute for the Science of Exploration Targets (ISET) team at the Southwest Research Institute and included Tim Swindle, director of the University of Arizona's Lunar and Planetary Laboratory.

Abell 3827 may show signs of self-interacting dark matter

Using the MUSE instrument on ESO's VLT in Chile, along with images from Hubble in orbit, a team of astronomers studied the simultaneous collision of four galaxies in the galaxy cluster Abell 3827. The team could trace out where the mass lies within the system and compare the distribution of the dark matter with the positions of the luminous galaxies.

Violent methane storms on Titan may solve dune direction mystery

With its thick, hazy atmosphere and surface rivers, mountains, lakes and dunes, Titan, Saturn's largest moon, is one of the most Earthlike places in the solar system.

As the Cassini-Huygens spacecraft examines Titan over many years, its discoveries bring new mysteries. One of those involves the seemingly wind-created sand dunes spotted by Cassini near the moon's equator, and the contrary winds just above.

In the Milky Way's stellar baby boom, Sol came late

In one of the most comprehensive multi-observatory galaxy surveys yet, astronomers find that galaxies like our Milky Way underwent a stellar "baby boom," churning out stars at a prodigious rate, about 30 times faster than today.

Our sun, however, is a late "boomer." The Milky Way's star-birthing frenzy peaked 10 billion years ago, but our sun was late for the party, not forming until roughly 5 billion years ago. By that time the star formation rate in our galaxy had plunged to a trickle.

The TRMM rainfall mission is about to end after 17 years

In 1997 when the Tropical Rainfall Measuring Mission, or TRMM, was launched, its mission was scheduled to last just a few years. Now, 17 years later, the TRMM mission has come to an end. NASA and the Japan Aerospace Exploration Agency (JAXA) stopped TRMM's science operations and data collection on April 8 after the spacecraft depleted its fuel reserves.

Magnetic activity bands and seasonal, year-long cycles on the Sun

Our sun is constantly changing. It goes through cycles of activity - swinging between times of relative calm and times when frequent explosions on its surface can fling light, particles and energy out into space. This activity cycle peaks approximately every 11 years. New research shows evidence of a shorter time cycle as well, with activity waxing and waning over the course of about 330 days.

Hubble discovers ghosts of quasars past

a set of enigmatic quasar ghosts -- ethereal green objects which mark the graves of these objects that flickered to life and then faded. The eight unusual looped structures orbit their host galaxies and glow in a bright and eerie goblin-green hue. They offer new insights into the turbulent pasts of these galaxies.

I see a red planet and I want it painted black

The planet Mercury’s puzzlingly dark color could result from its bombardment with carbon-rich micrometeorites, reports a study in Nature Geoscience. This may explain why the Moon is lighter in color than Mercury, even though the Moon’s surface contains more darkening iron.

Observations of Mercury reveal a planet that reflects little light and also has a low surface iron content, suggesting that another material is probably responsible for its observed dark surface. Comets are rich sources of carbon and they more frequently impact planets closer to the Sun.

Year in Space mission begins

Three crew members representing the United States and Russia are on their way to the International Space Station after launching from the Baikonur Cosmodrome in Kazakhstan at 3:42 p.m. EDT Friday (1:42 a.m., March 28 in Baikonur).

NASA astronaut Scott Kelly and Russian Federal Space Agency (Roscosmos) cosmonaut Mikhail Kornienko will spend about a year living and working aboard the space station to help scientists better understand how the human body reacts and adapts to the harsh environment of space.[image-51]

Ancient Martian lake system - evidence of two water-related events

A new analysis of an ancient Martian lake system in Jezero Crater, near the planet's equator, finds that the onslaught of water that filled the crater was one of at least two separate periods of water activity in the region surrounding Jezero.

Explosions of Jupiter's aurora linked to planet-moon interaction

On Earth, bursts of particles spewed by the Sun spark shimmering auroras, like the Northern Lights, that briefly dance at our planet's poles. But, on Jupiter, there's an auroral glow all the time, and new observations show that this Jovian display sometimes flares up because of a process having nothing to do with the Sun.

Our solar system may have once harbored Super-Earths

Long before Mercury, Venus, Earth, and Mars formed, it seems that the inner solar system may have harbored a number of super-Earths--planets larger than Earth but smaller than Neptune. If so, those planets are long gone--broken up and fallen into the sun billions of years ago largely due to a great inward-and-then-outward journey that Jupiter made early in the solar system's history.

Milky Way's center unveils supernova 'dust factory'

Sifting through the center of the Milky Way galaxy, astronomers have made the first direct observations - using an infrared telescope aboard a modified Boeing 747 - of cosmic building-block dust resulting from an ancient supernova.

Aurora australis: Aurora watchers shouldn't forget the Southern Lights

The past week saw a fantastic treat for aurora watchers. Generally it is the southern part of the country, Tasmania in particular, that sees the most impressive displays. But this aurora has been so intense that it was even seen across New South Wales and up around Brisbane it added a red glow to the sky.