Over the years, the spacefaring nations of Earth have sent dozens of probes and rovers to explore Mars. Today there are three active satellites circling the red planet while two rovers, Opportunity and Curiosity, wheel across the red sands below. Mars is dry, barren, and apparently lifeless.
Soon, those assets could find themselves exploring a very different kind of world.
"There is a small but non-negligible chance that Comet 2013 A1 will strike Mars next year in October of 2014," says Don Yeomans of NASA's Near-Earth Object Program at JPL. "Current solutions put the odds of impact at 1 in 2000."
The nucleus of the comet is probably 1 to 3 km in diameter, and it is coming in fast, around 56 km/s (125,000 mph). "It if does hit Mars, it would deliver as much energy as 35 million megatons of TNT," estimates Yeomans.
An artist's concept of the Wind spacecraft sampling the solar wind. Justin Kasper's science result is inset.
March 8, 2013: Using data from an aging NASA spacecraft, researchers have found signs of an energy source in the solar wind that has caught the attention of fusion researchers. NASA will be able to test the theory later this decade when it sends a new probe into the sun for a closer look.
The discovery was made by a group of astronomers trying to solve a decades-old mystery: What heats and accelerates the solar wind?
The solar wind is a hot and fast flow of magnetized gas that streams away from the sun's upper atmosphere. It is made of hydrogen and helium ions with a sprinkling of heavier elements. Researchers liken it to the steam from a pot of water boiling on a stove; the sun is literally boiling itself away.
“But,” says Adam Szabo of the NASA Goddard Space Flight Center, “solar wind does something that steam in your kitchen never does. As steam rises from a pot, it slows and cools. As solar wind leaves the sun, it accelerates, tripling in speed as it passes through the corona. Furthermore, something inside the solar wind continues to add heat even as it blows into the cold of space."
A video from the Goddard Space Flight Center recaps the discovery of the new radiation belt.
Earth's radiation belts were one of the first discoveries of the Space Age. A new finding published in today's issue of Science shows that we still have much to learn about them. NASA's twin Van Allen Probes, launched just last August, have revealed a previously unknown third radiation belt around Earth.
"Even 55 years after their discovery, Earth's radiation belts still are capable of surprising us," said Nicky Fox, Van Allen Probes deputy project scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "We thought we knew the radiation belts, but we don't."
Feb. 13, 2013: Rewind to the late 1950s. The Soviet Union had just launched the first artificial satellite, Sputnik. The United States, caught short, was scrambling to catch up, kick-starting a Cold War space race that would last for decades. Space was up for grabs, and it seemed like anything could happen.
Into this void stepped the United Nations. In 1958, the General Assembly "recognizing the common interest of mankind in furthering the peaceful use of outer space ... and desiring to avoid the extension of present national rivalries into this new field...." established the Committee on the Peaceful Uses of Outer Space (COPUOS). COPUOS became a forum for development of laws and treaties governing space-related activities. Moreover, it set the stage for international cooperation on problems that no one nation could handle alone.
As the years went by, COPUOS membership ballooned from 18 to 74 nations, while items such as space debris, near-Earth asteroids, space-based disaster management, and global navigation were added to the committee's regular agenda. At each annual meeting in Vienna, Austria, COPUOS members confer about these issues, which present some key challenge or peril to the whole planet.
The following article produced by Dr. Tony Philips gives an insight to NASA's Understanding on Solar Variability and Terrestrial Climate..
Jan. 8, 2013: In the galactic scheme of things, the Sun is a remarkably constant star. While some stars exhibit dramatic pulsations, wildly yo-yoing in size and brightness, and sometimes even exploding, the luminosity of our own sun varies a measly 0.1% over the course of the 11-year solar cycle.
There is, however, a dawning realization among researchers that even these apparently tiny variations can have a significant effect on terrestrial climate. A new report issued by the National Research Council (NRC), "The Effects of Solar Variability on Earth's Climate," lays out some of the surprisingly complex ways that solar activity can make itself felt on our planet.
The above graph from SpaceWeather.com is clear that the NOAA-led Solar Cycle Prediction Panel (red line) had absurdly overestimated solar activity in the current cycle 24. I would say:
1. Looking at those NOAA predictions they were obviously daft with abrupt changes in smoothed slope and curvature which makes one wonder what procedures they used to make these estimates.
2. Low solar cycles generally are longer than strong ones so even though some are saying the peak of 24 may have now passed it is reasonable to expect another (low) peak in this cycle - maybe around turn of 2013-14.
NOTE in an even cycle the activity - temp correlation is much weaker than in an odd cycle. So even if sunspot numbers go up by some amount there can still be plenty of solar-lunar driven extra cold.
Perhaps Solar Max is already here--or maybe it has already passed. This plot of measured vs. predicted sunspot numbers illustrates the idea.
SOLAR CYCLE UPDATE: 2013 is only days away, and according to most forecasters, Solar Max should be approaching as well. But is it? Barely-increasing sunspot counts and anemic solar activity suggest an interesting possibility: Perhaps Solar Max is already here--or maybe it has already passed.
The blue curve traces monthly sunspot numbers measured since 2000. The red curve is the prediction of the NOAA-led Solar Cycle Prediction Panel. So far, Solar Cycle 24 is underperforming even compared to the panel's low expectations.
There is still a strong chance that Cycle 24 will rebound and peak in 2013 as expected. It might even be a double-peaked cycle like the cycle before it. As 2013 nears only one thing is certain: we don't know what will happen. Stay tuned....
Looks like I'm not the only one who seems to think SC24 has already peaked.......
SO THIS IS SOLAR MAXIMUM? - SpaceWeather.com Forecasters have long expected the Solar Max of 2013 to be the weakest of the Space Age. It might be even weaker than they thought. As shown in this 20-year plot of sunspot counts vs. time, the sun is underperforming [above]
Sunspot numbers are notoriously variable, so the actual counts could rapidly rise to meet or exceed the predicted curve. For now, however, the face of the sun is devoid of large sunspots, and there have been no strong flares in more than a week. The threshold of Solar Max looks a lot like Solar Min.
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