Great look at the Sahara snows. Turns out snow in the Sahara while rare, is not unheard of.
NASA — For the second time in three years, snow has accumulated in the desert near the northern Algerian town of Aïn Séfra. Sometimes called the “gateway to the desert,” the town of 35,000 people sits between the Sahara and the Atlas Mountains. On January 8, Landsat 8 captured data for these natural-color images of the snow in the Sahara. The Landsat 8 image was draped over a global digital elevation model, built from data acquired by NASA’s Shuttle Radar Topography Mission.
According to news and social media accounts, anywhere from 10 to 30 centimeters (4 to 12 inches) of snow accumulated on January 8, 2018, on some higher desert elevations (1000 meters or more above sea level). Social media photos showed citizens sliding down snow-covered sand dunes. Warming temperatures melted much of it within a day.
Snow in the Sahara and other parts of North Africa is infrequent, but not unprecedented. Measurable snow fell near Aïn Séfra in December 2016. Substantial snow also blanketed the Atlas Mountains in Morocco in February 2012 and January 2005.
Image Credits: NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey and topographic data from the Shuttle Radar Topography Mission
Using actual scientific data along with Hollywood techniques, a team at the Space Telescope Science Institute in Baltimore, Maryland, and the Caltech/IPAC in Pasadena, California put together this excellent visualization. Thanks to NASA for the video.
I happened to think about the Parker Solar Probe scheduled to be launched between 31 July and 19 August 2018. This launch also uses the Delta IV the same family of lift vehicles as the NROL – 47 launch today uses although the Parker Solar Probe will use the Delta IV heavy.
There will be more about Parker Solar Probe coming in time and what a mission this will be. The probe will come within 5.95 million km / 3.7 million miles from the surface of the Sun at closest approach. Yes it will get HOT, the sun shade will reach an estimated 1,377 deg C / 2,500 deg F. The spacecraft will also be moving VERY fast at that point whizzing by at an astounding 700,000 kmh / 438,000 mph!!
The European Southern Observatory (ESO) just released this image of the surface of a red giant star. Take a look at our future. Excellent work! Image: ESO
ESO — Located 530 light-years from Earth in the constellation of Grus (The Crane), π1 Gruis is a cool red giant.
It has about the same mass as our Sun, but is 700 times larger and several thousand times as bright . Our Sun will swell to become a similar red giant star in about five billion years.
An international team of astronomers led by Claudia Paladini (ESO) used the PIONIER instrument on ESO’s Very Large Telescope to observe π1 Gruis in greater detail than ever before. They found that the surface of this red giant has just a few convective cells, or granules, that are each about 120 million kilometres across — about a quarter of the star’s diameter . Just one of these granules would extend from the Sun to beyond Venus. The surfaces — known as photospheres — of many giant stars are obscured by dust, which hinders observations. However, in the case of π1 Gruis, although dust is present far from the star, it does not have a significant effect on the new infrared observations .
Just look at the size of those nozzles! Well they have to be big, they will be at the base of the world’s most powerful rocket:
NASA — Space Launch System (SLS) solid rocket booster prime contractor Orbital ATK recently completed work at its Utah facilities on the booster nozzles for Exploration Mission-1 (EM-1), the first flight of SLS and the Orion spacecraft. SLS, the world’s most powerful rocket, and Orion will take humans on deep space missions, and the boosters provide most of the power to get the spacecraft off the ground. The powerhouse SLS five-segment solid rocket boosters are the largest ever built for flight and will provide more than 75 percent of the thrust during the first two minutes of spaceflight. Here, technicians are putting the finishing touches on the exit cones’ paint, including photogrammetric markings that will help engineers assess clearances between the boosters and ground structures during the initial moments after liftoff. At Kennedy Space Center in Florida during the integration phase of the program, the exit cones will be mated with the rest of the nozzle assemblies, which are also complete. During spaceflight, the booster nozzles direct the expanding gases from the burning solid propellant downward, helping the heavy-lift vehicle escape Earth’s gravity and send Orion to lunar orbit.
Just the other day I was wondering what was going on at Arecibo. You may recall Arecibo and the rest of Puerto Rico was pretty much turned into a disaster zone by Hurricane Maria. The rebuilding progress for Puerto Rico has been slow.
Arecibo on the other hand is apparently up and running just fine and it even got a look at asteroid Phaethon. Very pleased to hear of the return of this great observatory!
Original caption from NASA:
These radar images of near-Earth asteroid 3200 Phaethon were generated by astronomers at the National Science Foundation’s Arecibo Observatory on Dec. 17, 2017. Observations of Phaethon were conducted at Arecibo from Dec.15 through 19, 2017. At time of closest approach on Dec. 16 at 3 p.m. PST (6 p.m. EST, 11 p.m. UTC) the asteroid was about 6.4 million miles (10.3 million kilometers) away, or about 27 times the distance from Earth to the moon. The encounter is the closest the object will come to Earth until 2093.
The Arecibo Planetary Radar Program is funded by NASA’s Near-Earth Object Observations Program through a grant to Universities Space Research Association (USRA), from the Near-Earth Object Observations program. The Arecibo Observatory is a facility of the National Science Foundation operated under cooperative agreement by SRI International, USRA, and Universidad Metropolitana.
The busy week of launches wasn’t the only thing going on of course, NASA announced the discovery of an eighth planet around a star called Kepler-90. The discovery was made using AI and the system is as large as our own.
Big news indeed.
From NASA: Our solar system now is tied for most number of planets around a single star, with the recent discovery of an eighth planet circling Kepler-90, a Sun-like star 2,545 light years from Earth. The planet was discovered in data from NASA’s Kepler Space Telescope. This artist’s concept depicts the Kepler-90 system compared with our own solar system.
The newly-discovered Kepler-90i — a sizzling hot, rocky planet that orbits its star once every 14.4 days — was found using machine learning from Google. Machine learning is an approach to artificial intelligence in which computers “learn.” In this case, computers learned to identify planets by finding in Kepler data instances where the telescope recorded changes in starlight caused by planets beyond our solar system, known as exoplanets.
NASA Ames manages the Kepler and K2 missions for NASA’s Science Mission Directorate. JPL managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.
Image Credit: NASA/Ames Research Center/Wendy Stenzel