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Hurricanes Have No Place to Hide, Thanks to Better Satellite Forecasts
If you’ve ever looked at a hurricane forecast, you’re probably familiar with “cones of uncertainty,” the funnel-shaped maps showing a hurricane’s predicted path. Thirty years ago, a hurricane forecast five days before it made landfall might have a cone of uncertainty covering most of the East Coast. The result? A great deal of uncertainty about who should evacuate, where it was safe to go, and where to station emergency responders and their equipment.
Over the years, hurricane forecasters have succeeded in shrinking the cone of uncertainty for hurricane tracks, with the help of data from satellites. Polar-orbiting satellites, which fly nearly directly above the North and South Poles, are especially important in helping cut down on forecast error.
The orbiting electronic eyeballs key to these improvements: the Joint Polar Satellite System (JPSS) fleet. A collaborative effort between NOAA and NASA, the satellites circle Earth, taking crucial measurements that inform the global, regional and specialized forecast models that have been so critical to hurricane track forecasts.
The forecast successes keep rolling in. From Hurricanes Harvey, Irma and Maria in 2017 through Hurricanes Florence and Michael in 2018, improved forecasts helped manage coastlines, which translated into countless lives and property saved. In September 2018, with the help of this data, forecasters knew a week ahead of time where and when Hurricane Florence would hit. Early warnings were precise enough that emergency planners could order evacuations in time — with minimal road clogging. The evacuations that did not have to take place, where residents remained safe from the hurricane’s fury, were equally valuable.
The satellite benefits come even after the storms make landfall. Using satellite data, scientists and forecasters monitor flooding and even power outages. Satellite imagery helped track power outages in Puerto Rico after Hurricane Maria and in the Key West area after Hurricane Irma, which gave relief workers information about where the power grid was restored – and which regions still lacked electricity.
Flood maps showed the huge extent of flooding from Hurricane Harvey and were used for weeks after the storm to monitor changes and speed up recovery decisions and the deployment of aid and relief teams.
As the 2019 Atlantic hurricane season kicks off, the JPSS satellites, NOAA-20 and Suomi-NPP, are ready to track hurricanes and tropical cyclones as they form, intensify and travel across the ocean – our eyes in the sky for severe storms.
For more about JPSS, follow @JPSSProgram on Twitter and facebook.com/JPSS.Program, or @NOAASatellites on Twitter and facebook.com/NOAASatellites.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
Throwback Thursday: Frequently Asked Questions about Apollo
In celebration of the 50th anniversary of Apollo 11, we’ll be sharing answers to some frequently asked questions about the first time humans voyaged to the Moon. Answers have been compiled from archivists in the NASA History Office.
How many people worked on the Apollo program?
At the height of Apollo in 1965, about 409,900 people worked on some aspect of the program, but that number doesn’t capture it all.
It doesn’t represent the people who worked on mission concepts or spacecraft design, such as the engineers who did the wind tunnel testing of the Apollo Command Module and then moved on to other projects. The number also doesn’t represent the NASA astronauts, mission controllers, remote communications personnel, etc. who would have transferred to the Apollo program only after the end of Gemini program (1966-1967). There were still others who worked on the program only part-time or served on temporary committees. In the image above are three technicians studying an Apollo 14 Moon rock in the Lunar Receiving Laboratory at Johnson Space Center. From left to right, they are Linda Tyler, Nancy Trent and Sandra Richards.
How many people have walked on the Moon so far?
This artwork portrait done by spaceflight historian Ed Hengeveld depicts the 12 people who have walked on the Moon so far. In all, 24 people have flown to the Moon and three of them, John Young, Jim Lovell and Gene Cernan, have made the journey twice.
But these numbers will increase.
Are the U.S. flags that were planted on the Moon still standing?
Every successful Apollo lunar landing mission left a flag on the Moon but we don’t know yet whether all are still standing. Some flags were set up very close to the Lunar Module and were in the blast radius of its ascent engine, so it’s possible that some of them could have been knocked down. Neil Armstrong and Buzz Aldrin both reported that the flag had been knocked down following their ascent.
Our Lunar Reconnaissance Orbiter took photographs of all the Apollo lunar landing sites. In the case of the Apollo 17 site, you can see the shadow of the upright flag.
But why does it look like it’s waving?
The flags appear to “wave” or “flap” but actually they’re swinging. Swinging motions on Earth are dampened due to gravity and air resistance, but on the Moon any swinging motion can continue for much longer. Once the flags settled (and were clear of the ascent stage exhaust), they remained still. And how is the flag hanging? Before launching, workers on the ground had attached a horizontal rod to the top of each flag for support, allowing it to be visible in pictures and television broadcasts to the American public. Armstrong and Aldrin did not fully extend the rod once they were on the Moon, giving the flag a ripple effect. The other astronauts liked the ripple effect so much that they also did not completely extend the rod.
Why don’t we see stars in any of the pictures?
Have you ever taken a photo of the night sky with your phone or camera? You likely won’t see any stars because your camera’s settings are likely set to short exposure time which only lets it quickly take in the light off the bright objects closest to you. It’s the same reason you generally don’t see stars in spacewalk pictures from the International Space Station. There’s no use for longer exposure times to get an image like this one of Bruce McCandless in 1984 as seen from Space Shuttle Challenger (STS-41B).
The Hasselblad cameras that Apollo astronauts flew with were almost always set to short exposure times. And why didn’t the astronauts photograph the stars? Well, they were busy exploring the Moon!
When are we going back to the Moon?
The first giant leap was only the beginning. Work is under way to send the first woman and the next man to the Moon in five years. As we prepare to launch the next era of exploration, the new Artemis program is the first step in humanity’s presence on the Moon and beyond.
Keep checking back for more answers to Apollo FAQs.
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To the moon to stay
How We’re Accelerating Our Missions to the Moon
Our Space Launch System isn’t your average rocket. It is the only rocket that can send our Orion spacecraft, astronauts and supplies to the Moon. To accomplish this mega-feat, it has to be the most powerful rocket ever built. SLS has already marked a series of milestones moving it closer to its first launch, Artemis.
Here are four highlights you need to know about — plus one more just on the horizon.
Counting Down
Earlier this month, Boeing technicians at our Michoud Assembly Facility in New Orleans successfully joined the top part to the core stage with the liquid hydrogen tank. The core stage will provide the most of the power to launch Artemis 1. Our 212-foot-tall core stage, the largest the we have ever built, has five major structural parts. With the addition of the liquid hydrogen tank to the forward join, four of the five parts have been bolted together. Technicians are finishing up the final part — the complex engine section — and plan to bolt it in place later this summer.
Ready to Rumble
This August, to be exact. That’s when the engines for Artemis 1 will be added to the core stage. Earlier this year, all the engines for the first four SLS flights were updated with controllers, tested and officially cleared “go” for launch. We’ve saved time and money by modifying 16 RS-25 engines from the space shuttle and creating a more powerful version of the solid rocket boosters that launched the shuttle. In April, the last engine from the shuttle program finished up a four-year test series that included 32 tests at our Stennis Space Center near Bay St. Louis, Mississippi. These acceptance tests proved the engines could operate at a higher thrust level necessary for deep space travel and that new, modernized flight controllers —the “brains” of the engine — are ready to send astronauts to the Moon in 2024.
Getting a Boost
Our industry partners have completed the manufacture and checkout of 10 motor segments that will power two of the largest propellant boosters ever built. Just like the engines, these boosters are designed to be fast and powerful. Each booster burns 60 tons of propellant every second, generating a max thrust of 3.6 million pounds for two minutes of pure awesome. The boosters will finish assembly at our Kennedy Space Center in Florida and readied for the rocket’s first launch in 2020. In the meantime, we are well underway in completing the boosters for SLS and Orion’s second flight in 2022.
Come Together
Meanwhile, other parts of the rocket are finished and ready for the ride to the Moon. The final piece of the upper part of the rocket, the launch vehicle stage adapter, will soon head toward Kennedy Space Center in Florida. Two other pieces, including the interim cryogenic propulsion stage that will provide the power in space to send Orion on to the Moon, have already been delivered to Kennedy.
Looking to the Future
Our engineers evaluated thousands of designs before selecting the current SLS rocket design. Now, they are performing critical testing and using lessons learned from current assembly to ensure the initial and future designs are up to the tasks of launching exploration missions for years to come. This real-time evaluation means engineers and technicians are already cutting down on assembly time for future mission hardware, so that we and our partners can stay on target to return humans to the Moon by 2024 — to stay so we can travel on to Mars.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
Three Ways to Travel at (Nearly) the Speed of Light
One hundred years ago, Einstein’s theory of general relativity was supported by the results of a solar eclipse experiment. Even before that, Einstein had developed the theory of special relativity — a way of understanding how light travels through space.
Particles of light — photons — travel through a vacuum at a constant pace of more than 670 million miles per hour.
All across space, from black holes to our near-Earth environment, particles are being accelerated to incredible speeds — some even reaching 99.9% the speed of light! By studying these super fast particles, we can learn more about our galactic neighborhood.
Here are three ways particles can accelerate:
1) Electromagnetic Fields!
Electromagnetic fields are the same forces that keep magnets on your fridge! The two components — electric and magnetic fields — work together to whisk particles at super fast speeds throughout the universe. In the right conditions, electromagnetic fields can accelerate particles at near-light-speed.
We can harness electric fields to accelerate particles to similar speeds on Earth! Particle accelerators, like the Large Hadron Collider and Fermilab, use pulsed electromagnetic fields to smash together particles and produce collisions with immense amounts of energy. These experiments help scientists understand the Big Bang and how it shaped the universe!
2) Magnetic Explosions!
Magnetic fields are everywhere in space, encircling Earth and spanning the solar system. When these magnetic fields run into each other, they can become tangled. When the tension between the crossed lines becomes too great, the lines explosively snap and realign in a process known as magnetic reconnection. Scientists suspect this is one way that particles — for example, the solar wind, which is the constant stream of charged particles from the Sun — are sped up to super fast speeds.
When magnetic reconnection occurs on the side of Earth facing away from the Sun, the particles can be hurled into Earth’s upper atmosphere where they spark the auroras.
3) Wave-Particle Interactions!
Particles can be accelerated by interactions with electromagnetic waves, called wave-particle interactions. When electromagnetic waves collide, their fields can become compressed. Charged particles bounce back and forth between the waves, like a ball bouncing between two merging walls. These types of interactions are constantly occurring in near-Earth space and are responsible for damaging electronics on spacecraft and satellites in space.
Wave-particle interactions might also be responsible for accelerating some cosmic rays from outside our solar system. After a supernova explosion, a hot, dense shell of compressed gas called a blast wave is ejected away from the stellar core. Wave-particle interactions in these bubbles can launch high-energy cosmic rays at 99.6% the speed of light.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
God's voice vs satan's voice
Amen! 😇💪🏼
Jangan mengisi hati dan hidup anda dengan air comberan! 👍🏼👍🏼
Solid - smart work - bigger - faster - stronger