A total solar eclipse took place on 2 July 2019. It was visible in the South Pacific and the southern tip of South America. The eclipse was imaged by the NOAA GOES-West weather satellite stationed over the equator above the Pacific Ocean. The video plays the eclipse 3x.
Dark areas on the globe are nighttime. The shadow of the Moon appears at the sunrise night-to-day boundary in the South Pacific. It moves east toward the southern tip of South America. It disappears at the sunset day-to-night boundary.
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The Renewables 2019 Global Status Report (GSR 2019) is in its 15th year. This report by the coalition called REN21 supports the objective to accelerate the development of renewable energy and decrease fossil fuel use globally. REN21 gathers large bodies of renewable energy data to give a clear picture of what the industries are doing, where they are headed, and what policies guide them. The full report linked above is lengthy and comprehensive with numerous supporting charts and data. My shorter summary follows.
Renewable power generation is here to stay. Solar photovoltaics (PV) and wind are now major contributors in the power sector. A growing number of countries generate over 20% of their electricity with PV and wind. Bolder energy policies are needed to make these systems sustainable.
The heating, cooling, and transport sectors need stronger policies to supply cleaner air and energy security for users. Globally, these sectors historically rely on fossil fuels which are heavily subsidized in many countries. In addition, policy efforts focused on these sectors has been insufficient compared to the power sector. The report shows the need to create fairer competition, letting renewable energies thrive in their markets. Only on a level playing field can renewables displace carbon-emitting fossil fuels.
Many cities have adopted the most ambitious goals for renewables around the world. In many instances they exceed national and state/provincial goals. It is a growing trend.
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I like to watch movements of the planets which bring them into close encounters, or conjunctions. Some conjunctions are at a time and position in the sky so images taken over a few days can show their movements. Such was the case June 2019. A big challenge to getting well-timed images is cloud cover. We have had too much of it.
This image is a composite of three evenings of images looking west-northwest at 9:30pm. The camera was on a tripod at the same spot framing two light poles. I cut and pasted the locations of Mercury and Mars from the images taken on June 7 and June 20 onto this image taken on June 11. The dates for each are labeled. Click here or on the image to embiggen in a separate tab.
Note that Mercury, in yellow highlight, moved toward the upper left between June 7 and 11. It moved farther to the upper left by June 20. Mars, in white, moved down to the right between June 7 and 11. It continued down to the right by June 20. I hoped to image the two planets on June 17 or 18 when they appeared very close together, the width of a full moon. But clouds happened.
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Marit Jentoft-Nilsen and Robert Simmon
Atmospheric carbon dioxide has been monitored since 1958 at NOAA’s Mauna Loa Atmospheric Baseline Observatory in Hawaii. Values cycle up and down due to the amount of green vegetation available to convert CO2 to O2 by photosynthesis. Plants of the northern hemisphere reach maturity in June-August and reduce the level of CO2 from the previous month. Decomposition and respiration returns carbon dioxide to the atmosphere in the fall and winter. This is known as the fast carbon cycle. The carbon cycle of earth is discussed fully here.
The mean value of CO2 for May 2019 set the highest level in 61 yrs. This chart shows the monthly values plotted for the recent 5 years.
The full record for the Mauna Loa Observatory clearly shows the seasonal and long-term trends. The long-term rate is increasing evidenced by the greater steepness of the plot. More charts and analysis are available at this link.
If you have followed my blog long enough, you might recall that I like to photograph Iridium flares. Link to examples. The constellation of 66 communications satellites provides a worldwide phone system. I get email notices when a flare, sunlight reflecting off an antenna, is visible at my location.
Recently, I have received notices about flares from three weather satellites of the European Union (EUMETSAT). They are known as Metop A, B, and C. Their polar orbits and altitude allow weather to be monitored continuously. Antennae sometimes reflect bright sunlight down to Earth causing a flare. I was notified of one at 9:54pm local time on 9 Jun 2019.
Using the NightCap app on my iPad, I set it on the sidewalk, angled it toward the correct part of the sky and let it capture a time exposure for a couple of minutes. A small plane flew over at low altitude just after I started the exposure. Right after that, the Metop-C satellite passed over leaving a faint flare trail. Both were going north, lower left. Notice the handle of the Big Dipper drawn in the top left. The two pointer stars of the dipper are not visible. I like when serendipity happens.
I stepped outside and looked up toward the sun. An arc of faint color caught my attention. It was actually a full circle of color around the sun. These halos are 22˚ in radius from the sun caused by refraction of light through ice crystals of the high cirrus clouds between me and the sun. The color saturation has been enhanced a little to show the redness of the inner edge and blueness of the outer edge due to their different wavelengths of light.
I went out several minutes later. The cirrus clouds were gone, as was the halo. It was my lucky day.
The NASA Twins Study Science teams published their final stages of integrated research in the journal Science 12 April 2019. This video provides a short summary. More extensive details from each of the ten studies are explained in this article from NASA.
The Twins Study
How does an extended mission in space lasting as long as a year affect the human body? To answer that question, NASA used astronaut twins Mike Kelly and Scott Kelly as subjects. Scott spent 340 days aboard the Space Station from 27 March 2015 to 1 March 2016. Mike remained on Earth. Each was tested in a variety of ways by the research teams in order to compare results of long duration space flight.
Scott Kelly (left) and Mike Kelly (right) | NASA
Scott Kelly wrote the book Endurance about his experience. It is an excellent account of the lives of Mark and Scott, how they became astronauts, and behind the scenes events in the space program.
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