There's no shortage of stars to take in from this lovely spot on top of Hawaii's Mauna Kea Observatories. Michele Falzone/Photodisc/Getty Images All things considered, our atmosphere is pretty great. This blanket of nitrogen, oxygen and other gases keeps the world's temperature nice and habitable while protecting us from harmful UV radiation — to say nothing of the space debris it vaporizes. Oh yeah, and without all that oxygen in our atmosphere, animal life couldn't survive on planet earth. Not a bad resume. But despite its many good qualities, the atmosphere can be a nuisance to astronomy buffs. That's because it distorts light. At night, the atmosphere makes some heavenly bodies appear to flicker and shimmer. The technical term for this phenomenon is "astronomical scintillation." You probably know it by a different name: twinkling. Like an onion, the atmosphere is made up of layers. At the bottom is the troposphere, which starts right here at ground level on the planet's … [Read more...] about Why Do Stars Twinkle?
Why spots on moon
China is ready to go where no one has gone before. It's launching the Chang'e-4 lunar lander Friday on a mission to explore the side of the moon that never shows itself to us here on Earth.The Chinese government at a press conference in August gave the public a look at the rover Chang'e-4 will be carrying to the moon's surface.There's been little news out of China on the mission since then and it's not clear whether the launch will be televised anywhere. Chinese state media outlet Xinhua said in August that the public would be able to choose the name for the rover, but the moniker hasn't been revealed yet. Sources including journalist Andrew Jones, who covers China's space program, report that the launch is currently set for around 1:20 p.m. ET Friday from the Xichang Satellite Launch Center in southwest China using a Long March 3B rocket.The rover is actually the original backup to China's Jade Rabbit rover that landed on the moon in 2013; it has since been … [Read more...] about China will take historic road trip to the far side of the moon
This diagram shows the different phases of Earth's moon. Ron Miller/Stocktrek Images/Getty Images "Destroy All Monsters," a classic sci-fi movie from Japan's Toho Studios, predicted that mankind would colonize the moon by the year 1999. Needless to say, that didn't happen — and it still hasn't happened all these years later. But there have been serious talks about the feasibility of building a permanent lunar outpost or settlement. (A set of scientific papers released in 2016, for example, argued that a small moon base could be finished at a cost of $10 billion as soon as 2022.) Imagine what life would be like for the settlers up there. Among the many things they'd need to get used to are the long, cold nights that Earth's moon experiences . Yet despite the frigid temperatures, some lunar areas have brightly lit nighttimes. For those who dream of following in Neil Armstrong's footsteps, here's a short guide to lunar nights and lunar days. Phases and Faces With apologies to … [Read more...] about What Are Days and Nights Like on the Moon?
This close-up shows swirling clouds around Jupiter's famous Great Red Spot where scientists trained telescopes to learn more about the planet's water situation. NASA's Goddard Space Flight Center. Images courtesy of NASA/JPL Many mysteries hide beneath Jupiter's beautifully chaotic clouds, but with the help of some clever astronomical techniques and NASA's Juno spacecraft, one of the giant planet's biggest puzzles may be closer to being solved. As we know, water is the key to life on Earth. Our efforts to seek out life on other worlds hinges on the detection of this important compound. Though scientists don't think that life inhabits Jupiter, finding a Jovian reservoir is one of the most pressing issues in planetary science. Locating this water will help us understand how the solar system, and Jupiter itself, evolved. Unfortunately, Jupiter has been notoriously bad at revealing any water deep in its thick atmosphere, leaving scientists and their models of planetary formation high … [Read more...] about The Great Red Spot May Expose Jupiter’s Watery Secret
It's low tide at Robin Hood's Bay, North Yorkshire, which is a popular scenic area of the Northeast coast of England. Photos by R A Kearton/Getty Images Tides have caused a lot of trouble recently. During high tide periods, low-lying areas that border the ocean now flood way more often than they used to. Between 2000 and 2017, the average frequency of "high tide flooding" across the United States increased by 50 percent. Floods of this sort block roadways, harm infrastructure, and back up storm drains. Around 40 percent of the global population lives within 62 miles (100 kilometers) of a coastline. Recent flood trends must have a lot of these people wondering about tidal science. How do tides happen? Why do some areas get more dramatic tides than others? And why can't the sea level just stay constant everywhere, all the time? Today we're going to look at the physics and idiosyncrasies of planet Earth's tides. Pushing Water Check out the diagram below. In the picture, you will … [Read more...] about What Causes High Tide and Low Tide? Why Are There Two Tides Each Day?