Paris (AFP) – The Moon, our planet’s constant companion for some 4.5 billion years, may have been forged by a rash of smaller bodies smashing into an embryonic Earth, researchers said Monday.
Such a bombardment birth would explain a major inconsistency in the prevailing hypothesis that the Moon splintered off in a single, giant impact between Earth and a Mars-sized celestial body.
“The multiple impact scenario is a more ‘natural’ way of explaining the formation of the Moon.”
In such a scenario, scientists expect that about a fifth of the Moon’s material would have come from Earth and the rest from the impacting body.
Yet, the makeup of the Earth and the Moon are near identical — an improbability that has long perplexed backers of the single-impact hypothesis.
“In the early stages of the Solar System, impacts were very abundant, therefore it is more natural that several common impactors formed the Moon rather than one special one.”
“The multiple impact scenario is a more ‘natural’ way of explaining the formation of the Moon,” said Raluca Rufu of the Weizmann Institute of Science in Rehovot, who co-authored the new study published in the journal Nature Geoscience.
Such multiple hits would have excavated more Earth material than a single one, which means the moonlets would more closely resemble our planet’s composition, said the study authors. Read the rest of this entry »
NASA’s Solar Dynamics Observatory (SDO) was commanded to roll 360 degrees on one axis. The maneuver was performed in 7 hours and time-lapsed here. It’s done to take ‘precise measurements of the solar limb’ according to the SDO team at NASA’s Goddard Space Flight Center.
The sun appears to take a dizzying flip in a new video captured by NASA’s Solar Dynamics Observatory (SDO) spacecraft .
SDO did a full somersault on July 6 over the course of about 7 hours, taking pictures of the sun every 12 seconds all the while.
These photos, which SDO team members combined into a video, are pretty wild.
The video seems “to show the sun spinning, as if stuck on a pinwheel,” NASA officials wrote in an image description Friday (July 15).
It’s now officially spring! These are the funny ring-tailed Lemurs from the Twycross Zoo in Atherstone, England. As soon as just a bit of sun comes, that’s it, arms are stretched out to catch some Sun rays.
[VIDEO] Robotic Spacecraft MESSENGER Is Out of Fuel, Doomed to Crash Into Mercury This Afternoon at More Than 8,750 MPHPosted: April 30, 2015
The robotic spacecraft MESSENGER has run out of fuel. With no way to make major adjustments to its orbit around the planet Mercury, the probe will smash into the surface at more than 8,750 miles per hour (3.91 kilometers per second). The impact will add a new crater to the planet’s scarred face that engineers estimate will be as wide as 52 feet (16 meters).
— ABC News (@ABC) February 10, 2015
Sun’s Solar Flares Captured on NASA Video
The sun emitted a significant solar flare, peaking at 7:24 p.m. EST on Dec. 19, 2014. NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer
(AFP)—Americans are enthusiastic about the promise of science but lack basic knowledge of it, with one in four unaware that the Earth revolves around the Sun, said a poll out Friday.
The survey included more than 2,200 people in the United States and was conducted by the National Science Foundation.
Nine questions about physical and biological science were on the quiz, and the average score — 6.5 correct — was barely a passing grade.
Just 74 percent of respondents knew that the Earth revolved around the Sun, according to the results released at the American Association for the Advancement of Science meeting in Chicago.
Fewer than half (48 percent) knew that human beings evolved from earlier species of animals.
Forecasters at NOAA’s Space Weather Prediction Center said a coronal mass ejection (CME) arrived near Earth at 2:32 p.m. EST, Jan. 9, 2014, which initiated the start of a geomagnetic storm. Effects from the storm are expected to continue through January 10, with minor disruptions to communications and GPS.
Download here. (Credit: NOAA)
The sunspot in Region 1944 produced the eruption at 1:32 p.m. EST Tuesday, Jan. 7, 2014, and remains active and is well positioned to deliver more storm activity in the next several days. NOAA’s SWPC will continue to monitor the region for activity.
How space weather affects real-time technology
Economies around the world have become increasingly vulnerable to the ever-changing nature of the sun. Solar flares can disrupt power grids, interfere with high-frequency airline and military communications, disrupt Global Positioning System (GPS) signals, interrupt civilian communications, and blanket the Earth’s upper atmosphere with hazardous radiation.
Monitoring and forecasting solar outbursts in time to reduce their effect on space-based technologies have become new national priorities. And NOAA’s Space Weather Prediction Center (SWPC), part of NOAA’s National Weather Service, is the nation’s official source of space weather forecasts, alerts, and warnings.
The meteor that injured more than 1,500 people when it exploded and showered debris over Russia in February may have had a close shave with the Sun earlier, researchers said.
A study of its composition showed the space rock had undergone “intensive melting” before entering Earth’s atmosphere and streaking over the central Russia’s Chelyabinsk region in a blinding fireball, they said in a statement.
Warming Cooling Alarmism
During the 1970s the media promoted global cooling alarmism with dire threats of a new ice age. Extreme weather events were hyped as signs of the coming apocalypse and man-made pollution was blamed as the cause. Environmental extremists called for everything from outlawing the internal combustion engine to communist style population controls. This media hype was found in newspapers, magazines, books and on television;
“The ice age is due now anytime”
– Professor George Kukla, Columbia University, 1974
“Climate experts believe the next ice age is on its way.”
– Leonard Nimoy, 1978
The sun is gearing up for a major solar flip, NASA says.
In an event that occurs once every 11 years, the magnetic field of the sun will change its polarity in a matter of months, according new observations by NASA-supported observatories.
The flipping of the sun’s magnetic field marks the peak of the star’s 11-year solar cycle and the halfway point in the sun’s “solar maximum” — the peak of its solar weather cycle. NASA released a new video describing the sun’s magnetic flip on Monday (Aug. 5).
“It looks like we’re no more than three to four months away from a complete field reversal,” Todd Hoeksema, the director of Stanford University’s Wilcox Solar Observatory, said in a statement. “This change will have ripple effects throughout the solar system.”
As the field shifts, the “current sheet” — a surface that radiates billions of kilometers outward from the sun’s equator — becomes very wavy, NASA officials said. Earth orbits the sun, dipping in and out of the waves of the current sheet. The transition from a wave to a dip can create stormy space weather around Earth, NASA officials said.
“The sun’s polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity,” Stanford solar physicist Phil Scherrer said in a statement. “This is a regular part of the solar cycle.”
While the polarity shift can stir up some stormy weather, it also provides extra shielding from dangerous cosmic rays. These high-energy particles, which are accelerated by events like supernova explosions, zip through the universe at nearly the speed of light. They can harm satellites and astronauts in space, and the wrinkled current sheet better protects the planet from these particles.
The effects of the rippled sheet can also be felt throughout the solar system, far beyond Pluto and even touching the Voyager probes near the barrier of interstellar space.
“The sun’s north pole has already changed sign, while the south pole is racing to catch up,” Scherrer said. “Soon, however, both poles will be reversed, and the second half of solar max will be underway.”
The current solar maximum is the weakest in 100 years, experts have said. Usually, at the height of a solar cycle, sunspot activity increases. These dark regions on the sun’s surface can give birth to solar flares and ejections, but there have been fewer observed sunspots this year than in the maximums of previous cycles.