Tag Archives: earth

Littlest Continent Had Biggest Role in Sea Level Drop

A unique and complex set of circumstances came together over Australia from 2010 to 2011 to cause Earth’s smallest continent to be the biggest contributor to the observed drop in global sea level rise during that time, finds a new study co-authored and co-funded by NASA.

In 2011, scientists at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the University of Colorado at Boulder reported that between early 2010 and summer 2011, global sea level fell sharply, by about a quarter of an inch, or half a centimeter. Using data from the NASA/German Aerospace Center’s Gravity Recovery and Climate Experiment (GRACE) spacecraft, they showed that the drop was caused by the very strong La Nina that began in late 2010. That La Nina changed rainfall patterns all over our planet, moving huge amounts of Earth’s water from the ocean to the continents. The phenomenon was short-lived, however. (more…)

Read More

Scientists want a detailed picture of Mount St. Helens’ plumbing

Earth scientists are laying plans for a two-year study covering a broad area of southwestern Washington to develop a better understanding of how Mount St. Helens gets its supply of volcanic magma.

“The main goal is to understand the plumbing system of the mountain,” said Kenneth Creager, a University of Washington professor of Earth and space sciences who is leading the study. (more…)

Read More

How Did Earth’s Primitive Chemistry Get Kick Started?

How did life on Earth get started? Three new papers co-authored by Mike Russell, a research scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., strengthen the case that Earth’s first life began at alkaline hydrothermal vents at the bottom of oceans. Scientists are interested in understanding early life on Earth because if we ever hope to find life on other worlds — especially icy worlds with subsurface oceans such as Jupiter’s moon Europa and Saturn’s Enceladus — we need to know what chemical signatures to look for.

Two papers published recently in the journal Philosophical Transactions of the Royal Society B provide more detail on the chemical and precursor metabolic reactions that have to take place to pave the pathway for life. Russell and his co-authors describe how the interactions between the earliest oceans and alkaline hydrothermal fluids likely produced acetate (comparable to vinegar). The acetate is a product of methane and hydrogen from the alkaline hydrothermal vents and carbon dioxide dissolved in the surrounding ocean. Once this early chemical pathway was forged, acetate could become the basis of other biological molecules. They also describe how two kinds of “nano-engines” that create organic carbon and polymers — energy currency of the first cells — could have been assembled from inorganic minerals. (more…)

Read More

Solar tsunami used to measure Sun’s magnetic field

A solar tsunami observed by NASA’s Solar Dynamics Observatory (SDO) and the Japanese Hinode spacecraft has been used to provide the first accurate estimates of the Sun’s magnetic field.

Solar tsunamis are produced by enormous explosions in the Sun’s atmosphere called coronal mass ejections (CMEs). As the CME travels out into space, the tsunami travels across the Sun at speeds of up to 1000 kilometres per second.

Similar to tsunamis on Earth, the shape of solar tsunamis is changed by the environment through which they move. Just as sound travels faster in water than in air, solar tsunamis have a higher speed in regions of stronger magnetic field. This unique feature allowed the team, led by researchers from UCL’s Mullard Space Science Laboratory, to measure the Sun’s magnetic field. The results are outlined in a paper soon to be published in the journal Solar Physics. (more…)

Read More

Using earthquake sensors to track endangered whales

The fin whale is the second-largest animal ever to live on Earth. It is also, paradoxically, one of the least understood. The animal’s huge size and global range make its movements and behavior hard to study.

A carcass that washed up on a Seattle-area beach this spring provided a reminder that sleek fin whales, nicknamed “greyhounds of the sea,” are vulnerable to collision when they strike fast-moving ships. Knowing their swimming behaviors could help vessels avoid the animals. Understanding where and what they eat could also help support the fin whale’s slowly rebounding populations. (more…)

Read More

Star with flare

NASA telescope provides insights into unusual dwarf star

Astronomer John Gizis of the University of Delaware, working with data obtained by NASA’s Kepler telescope, is studying a highly unusual dwarf star and its powerful flares that may hold clues to the likelihood of life on other planets as well as to the behavior of our sun.

Gizis, associate professor in the Department of Physics and Astronomy, discovered the star two years ago using a ground-based telescope and now has conducted additional research using Kepler observations over the past two years. (more…)

Read More

Moon and Earth have common water source

Researchers used a multicollector ion microprobe to study hydrogen-deuterium ratios in lunar rock and on Earth. Their conclusion: The Moon’s water did not come from comets but was already present on Earth 4.5 billion years ago, when a giant collision sent material from Earth to form the Moon.

PROVIDENCE, R.I. [Brown University] —Water inside the Moon’s mantle came from primitive meteorites, new research finds, the same source thought to have supplied most of the water on Earth. The findings raise new questions about the process that formed the Moon. (more…)

Read More

Marks on Martian Dunes May Be Tracks of Dry-Ice Sleds

PASADENA, Calif. — NASA research indicates hunks of frozen carbon dioxide — dry ice — may glide down some Martian sand dunes on cushions of gas similar to miniature hovercraft, plowing furrows as they go.

Researchers deduced this process could explain one enigmatic class of gullies seen on Martian sand dunes by examining images from NASA’s Mars Reconnaissance Orbiter (MRO) and performing experiments on sand dunes in Utah and California. (more…)

Read More