Tag Archives: Meteorology

Storms on Earth create antimatter blasts in space

Star Trek fans will be familiar with the term “positron,” if not necessarily what a positron is. I’ll admit that, before researching this article, I certainly did not. But it now appears that the colossally powerful energy bursts that we call lightning are only part of the amazing energy interaction happening in our skies every day. And the other one includes a blast of.. positrons.

The Fermi Gamma Radiation Telescope is a satellite telescope run by NASA whose job it is to detect the presence of antimatter, which scientists expected to see streaming out of distant stars or black holes. When the satellite was hit by a blast of positron particles, a type of antimatter, the were surprised to find that the source was actually here on our own Earth:

Researchers studying thunderstorms have made a surprising discovery: The lightning we see with our eyes has a dark competitor that discharges storm clouds and flings antimatter into space. Astrophysicists and meteorologists are scrambling to understand “dark lightning.”

This “Dark Lightning” is yet another chain reaction that happens when electromagnetic energy builds up in clouds. Whereas electrons in lightning zap from one charged area to another, causing the brilliant bolts of energy we are familiar with, another reaction causes nearly-invisible (dark) bursts of electrons directly up and out of the cloud. This “avalanche,” as the video below describes it, causes a chain reaction that creates a short-term particle collider that shoots gamma radiation, and now we discover, positrons out into the universe.

So, what is a positron and what is antimatter? Particle physicists discovered long ago that, in order for the math of particle dynamics to work out right, every type of particle needed to have a nearly exact opposite version. Nearly, that is, in that the “Bizarro Particle” must have the same mass and an opposite value such as electrical charge. Neutrons can only exist if antineutrons can also exist; protons can only exist if antiprotons exist. And electrons can only exist if positrons – positively charged particles of the same mass as electrons – also exist. The confusing bit in this case is that we tend to think of electrons and protons as being opposite – and they are oppositely charged, but have different masses and are fundamentally different particles.

Collectively, all these antiparticles are known as antimatter. And far from being hypothetical as so much of modern quantum physics is, positrons have been detected regularly as early as 1932. For a much more in-depth primer on antimatter, read this excellent piece from Scientific American. Now, the video:

Martian blueberries, dry ice snowfalls and Curiosity tests robotic arm

The rate at which we are getting data back from Mars continues to amaze me. We have two working robots on the surface of Mars, plus the Mars Reconnaissance Orbiter, all beaming back new information in what seems like daily increments. With that in mind, I thought I’d summarize the current state of the Mars project as it happens.

“Blueberries” and.. not “blueberries”:

A subject on which I’m just catching up now. Apparently, the Mars rover Opportunity has been studying what scientists have nicknamed “blueberries” on the surface of Mars since it landed. The blueberries are actually round pellets of iron-rich sedimentary rock that scientists believe were formed when Mars still had liquid water on its surface.

But what Opportunity has discovered nowis a bit of a mystery. They look similar, but apparently have a completely different composition. Scientists used a laser spectrometer to analyze the contents and discovered that the new spherules have concentric spheres of composition. “They seem to be crunchy on the outside, and softer in the middle,” says Steve Squyres of Cornell University.

So… apparently, Mars is the Home of the Whopper? Time will tell..

Dippin’ Dots, my ass.

Curiosity flexes its arm:

Curiosity continues to go through system-wide diagnostics as it preps for its mission. One major component of the Mars Curiosity Rover is its robotic arm, loaded to the gills with scientific whiz-bang. Since September 5th, JPL engineers have been testing out the 7 foot long arm and its tools, getting ready for Curiosity to touch its first Martian rocks.

The robotic arm includes the Alpha Particle X-Ray Spectrometer (APXS), which is the same technology Opportunity used to test the composition of the blueberries. The arm is also equipped with a camera which it can use to take close-up, color photos of rocks. The press release notes that this is the fifth week of a two year mission, but doesn’t say what the next step will be.

Let it snow, let it snow, let it snow!:

For those of you dreading the oncoming Rochester winter, take heart! There is in fact a place with even shittier winters: the southern pole of Mars.

Scientists analyzing data from the Mars Reconnaissance Orbiter have discovered the best evidence yet that winter on Mars brings carbon dioxide snowfalls to its south pole. While scientists have known about carbon dioxide ice on the polar caps for decades, this represents the first time they’ve been able to show evidence that the atmosphere produces carbon dioxide clouds that grow thick enough to produce precipitation. Carbon dioxide, remember, freezes at -193°.

So, like, buck up, Rochesterians!

Bundle up! How dew point affects temperature as Rochester chills for fall.

As seasons change and days become shorter, Rochesterians begin to brace themselves for another long winter. Opening the front door on an early fall morning, you may expect familiar summer air only to be rudely welcomed by a blanket of frost.

Long before winter makes her presence felt on the northeast, the transition into fall not only brings the beauty of radiant deciduous trees but also the cool, crisp air of autumn.  Did you ever wonder why during this period, daytime temperatures may still climb into the 80s but come nightfall, temperatures dip well into the 40s? Or in a matter of minutes following sunset, temperatures will drop ten or almost twenty degrees?

This is a direct result of a decrease of daily dew point temperatures. The dew point temperature is the temperature at which the air needs to cool to reach saturation. What does this mean? Essentially, dew point temperature is the measure of water vapor or moisture in the air. To grasp the idea of dew point temperature, think back two months to the unbearably muggy days of July. At some point everyone has said, “It’s way too hot outside”. Hot temperatures are exacerbated by exceptionally high dew point temperatures (approximately 65° and greater) not allowing perspiration or sweat to evaporate efficiently, which creates an oppressively hot, sticky feeling.

This week, Rochesterians have begun to experience “fall” like weather, especially in the mornings. Sure colder temperatures are associated with this feeling.  However, fall brings a certain crisp, dry air, allowing more evaporation of perspiration, and thus comfortable conditions.

Since the dew point temperature is the temperature at which air needs to cool to reach saturation, it is important to note that temperature cannot be lower than dew point temperature. Thus, one can use this fact to help predict the low temperature for a given day.  When the sun sets and earth cools due to lack of incoming solar radiation (heat from sun), the temperature will usually cool to around the dew point temperature. This is why lows in the summer often stay in the mid 60s or even 70s while lows in early autumn will drop into the 40s or below.

Dew point temperature and air temperature can be equal to one another though, which results in 100% relative humidity causing the air to condense and form early morning dew. As fall progresses, temperatures continue to drop, along with the dew point temperature, eventually falling below the freezing mark (32°F).  When the relative humidity is 100% and the temperature is below freezing, water in the air deposits on the ground as frost.

When frost coats the ground for the first time in autumn, it’s a sure thing that beach season has come to an unfortunate end.