Aboard The International Space Station, Astronaut Thomas Pesquet of The European Space Agency Snapped

TODAY IN HISTORY: The first-ever color image of Mars, taken by NASA’s Viking 1 lander on July 21, 1976. (San Diego Air & Space Museum)

Does an ecplispe cause any unusual effects on the Earth?

Yes, and this is one of the things we’re hoping to study more with this eclipse! If you are in totality, you’ll notice a significant temperature drop. We are also expecting to see changes in the Earth’s atmosphere and ionosphere. You can help us document these changes using the GLOBE Observer app https://www.globe.gov/globe-data/data-entry/globe-observer ! There are lots of great citizen science going on during this eclipse, and we’d love to have everyone here helping out! https://eclipse2017.nasa.gov/citizen-explorers

New Horizons Flyover of Pluto

Using actual New Horizons data and digital elevation models of Pluto and its largest moon Charon, mission scientists have created flyover movies that offer spectacular new perspectives of the many unusual features that were discovered and which have reshaped our views of the Pluto system – from a vantage point even closer than the spacecraft itself. This dramatic Pluto flyover begins over the highlands to the southwest of the great expanse of nitrogen ice plain informally named Sputnik Planitia. The viewer first passes over the western margin of Sputnik, where it borders the dark, cratered terrain of Cthulhu Macula, with the blocky mountain ranges located within the plains seen on the right. The tour moves north past the rugged and fractured highlands of Voyager Terra and then turns southward over Pioneer Terra – which exhibits deep and wide pits – before concluding over the bladed terrain of Tartarus Dorsa in the far east of the encounter hemisphere. Digital mapping and rendering were performed by Paul Schenk and John Blackwell of the Lunar and Planetary Institute in Houston.

Mosaic of the nebulae in the Orion Constellation

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Ep.17 Edmond Halley - HD and the Void

Edmond Halley was heavily involved in the establishment of modern astronomy, whether through his direct observational work or through the support he offered others in his field. Hear a quick overview of the man who's popped up so much throughout t...

I’m back! July was nuts! June was also nuts! I’ve missed this podcast, though, and have been thinking about it the entire time because I will never stop loving space. I was working my way through a very meaty book on Edmond Halley and I am here to report on my findings, and also compile some of the things I’ve already said about this cool guy and his cool contributions to science.

Below the cut are my standard glossary, transcript, timeline of people mentioned, sources, and music credits. I take topic suggestions from Tumblr messages, you can tweet at me on Twitter at @HDandtheVoid, or you can ask me to my face if you know me. Subscribe on iTunes to get the new episodes of my increasingly erratically updated podcast, and please please please rate and review it. Go ahead and tell friends if you think they’d like to hear it, too!

(My thoughts on the next episode are Stephen Hawking and his theories or famous comets. The next episode will go up in August—hopefully August 20th!)

Glossary

sidereal year—the time required for the earth to complete an orbit of the sun relative to the stars.

tropical year—the interval at which seasons repeat and the basis for the calendar year.

Script/Transcript

Timeline

Julius Caesar, Roman (100-45 BCE)

Augustus Caesar, Roman (63-14 BCE) 

Nicolaus Copernicus, Polish (1473-1543)

Pope Gregory XIII, Italian (1502-1585)

Tycho Brahe, Danish (1546-1601)

Johannes Kepler, German (1571-1630)

Johannes Hevelius, Polish (1611-1687)

Giovanni Cassini (in French, Jean-Dominique Cassini), Italian/French (1625-1712)

Queen Christina, Swedish (1626-1689)

Isaac Newton, English (1643-1727)

John Flamsteed, English (1646-1719)

Elisabeth Hevelius, Polish (1647-1693)

Edmond Halley, English (1656-1742)

John Harrison, English (1693-1776)

Sources

Morse, Stephen P. “The Julian Calendar and why we need to know about it.” The Association of Professional Genealogists Quarterly (March 2014). Accessed July 15, 2018.

Julian Date Converter via the Astronomical Applications Department of the U.S. Naval Observatory.

Hughes, David W. “Edmond Halley, Scientist.” British Astronomical Association (1985). Accessed July 27, 2018.

Cook, Alan. Edmond Halley: Charting the Heavens and the Seas. Clarendon Press: Oxford, 1998.

Intro Music: ‘Better Times Will Come’ by No Luck Club off their album Prosperity

Outro Music: ‘Fields of Russia’ by Mutefish off their album On Draught

I just watched the 4 clearly visible planets march across the sky with the moon in the center, so here’s a short guide to the night sky as the last 3 move across.

mammenxTime lapse of the milky way rolling across the night sky, flanked by the planets Jupiter, Saturn & Mars. Taken from Diskit Ladakh, this place truly has some fantastic unobstructed views of the night sky

What's Made in a Thunderstorm and Faster Than Lightning? Gamma Rays!

A flash of lightning. A roll of thunder. These are normal stormy sights and sounds. But sometimes, up above the clouds, stranger things happen. Our Fermi Gamma-ray Space Telescope has spotted bursts of gamma rays - some of the highest-energy forms of light in the universe - coming from thunderstorms. Gamma rays are usually found coming from objects with crazy extreme physics like neutron stars and black holes. 

So why is Fermi seeing them come from thunderstorms?

Thunderstorms form when warm, damp air near the ground starts to rise and encounters colder air. As the warm air rises, moisture condenses into water droplets. The upward-moving water droplets bump into downward-moving ice crystals, stripping off electrons and creating a static charge in the cloud.

The top of the storm becomes positively charged, and the bottom becomes negatively charged, like two ends of a battery. Eventually the opposite charges build enough to overcome the insulating properties of the surrounding air - and zap! You get lightning.

Scientists suspect that lightning reconfigures the cloud’s electrical field. In some cases this allows electrons to rush toward the upper part of the storm at nearly the speed of light. That makes thunderstorms the most powerful natural particle accelerators on Earth!

When those electrons run into air molecules, they emit a terrestrial gamma-ray flash, which means that thunderstorms are creating some of the highest energy forms of light in the universe. But that’s not all - thunderstorms can also produce antimatter! Yep, you read that correctly! Sometimes, a gamma ray will run into an atom and produce an electron and a positron, which is an electron’s antimatter opposite!

The Fermi Gamma-ray Space Telescope can spot terrestrial gamma-ray flashes within 500 miles of the location directly below the spacecraft. It does this using an instrument called the Gamma-ray Burst Monitor which is primarily used to watch for spectacular flashes of gamma rays coming from the universe.

There are an estimated 1,800 thunderstorms occurring on Earth at any given moment. Over the 10 years that Fermi has been in space, it has spotted about 5,000 terrestrial gamma-ray flashes. But scientists estimate that there are 1,000 of these flashes every day - we’re just seeing the ones that are within 500 miles of Fermi’s regular orbits, which don’t cover the U.S. or Europe.

The map above shows all the flashes Fermi has seen since 2008. (Notice there’s a blob missing over the lower part of South America. That’s the South Atlantic Anomaly, a portion of the sky where radiation affects spacecraft and causes data glitches.)

Fermi has also spotted terrestrial gamma-ray flashes coming from individual tropical weather systems. The most productive system we’ve seen was Tropical Storm Julio in 2014, which later became a hurricane. It produced four flashes in just 100 minutes!

Learn more about what Fermi’s discovered about gamma rays over the last 10 years and how we’re celebrating its accomplishments.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

The Crab Nebula

via reddit