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A weekly discussion of what's new and interesting in astronomy with astronomer Derrick Pitts and WHHY FM's Dave Heller.

A weekly discussion of what's new and interesting in astronomy with astronomer Derrick Pitts and WHHY FM's Dave Heller.
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Location:

United States

Networks:

WHYY

Description:

A weekly discussion of what's new and interesting in astronomy with astronomer Derrick Pitts and WHHY FM's Dave Heller.

Language:

English


Episodes

Going in Circles

11/10/2018
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This week, astronomers are studying a pair of stars that rotate around their common point once every 3 hours. The stars are buried in a planetary nebula 14,000 light years from Earth in Canis Major. Researchers think material from the bigger star of the pair bridges over onto the smaller but more energetic white dwarf star, causing intermittent nuclear bomb-sized explosions. Typically, these stars start much farther apart, then spin in together. In this case they’re already almost...

Duration:00:05:24

Fall Back

11/2/2018
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Enjoy an earlier sunrise starting Sunday morning, when our area reverts to Eastern Standard Time. The earlier sunsets affords opportunities to view the glories of the night sky. Saturn and Mars are easy targets; Saturn in the southwest and Mars in the south at 5:30pm. In this time when accusations of ‘fake news’ are often invoked, let’s pay tribute to a long-ago radio broadcast that laid the groundwork. It was 80 years ago this week that Orson Welles broadcast his famous radio performance...

Duration:00:06:37

Sun Day

10/29/2018
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Our sun, some 865,000 miles in diameter, rotates once every 30-35 days or so; fairly normal for a star like ours. Contrast that with an example of a neutron star (aka pulsar) – a mere 12.5 miles in diameter – that rotates once every 1.4 milliseconds, or 42,960 times every minute! Typically pulsars emit electromagnetic radiation in beams that emanate from their magnetic poles, much like a coastal lighthouse has s weeping rotting beam. To0 detect a pulsar, its beam has to be pointed in our...

Duration:00:06:12

International Observe the Moon Night

10/20/2018
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The naked eye is just fine – but if the night sky is clear this evening, the best way to view the moon is with a pair of binoculars, revealing craters, seas, bays and more. In addition, Saturn and Mars are still hanging in the early evening sky. The constellations Pegasus, Andromeda, Cassiopeia and Perseus are rising in the east. Tomorrow marks the 95th year since attendees took in the first planetarium show, at the Deutches Museum in Munich, Germany. Actually, indoor depictions of the...

Duration:00:05:06

Shooting Stars

10/16/2018
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Buried in the data from European Space Agency’s Gaia Survey satellite, astronomers from Leiden University in the Netherlands discovered 13 new stars whose hyper-velocities suggest they’ve interlopers from EXTRA-galactic sources (outside our Milky Way). Seven others are traveling at several hundreds of millions of miles per hour. They’ll escape our galaxy and head off into intergalactic space. Astronomers have little understanding of how such velocities are generated. By the way; for...

Duration:00:04:31

The Goblin

10/9/2018
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Scientists who confirmed the existence of 2015 TG387 out beyond the Kuiper Belt believe its orbit offers the best evidence of the existence of the long-speculated Planet X in our solar system. 2015 TG387 (aka “The Goblin”) is a trans-Neptunian object around 200 miles in diameter. It was first observed at Mauna Kea Observatories on October 13, 2015, by astronomers David J. Tholen, Scott S. Sheppard, and Chad Trujillo, and publicly announced on October 1, 2018. 2015 TG387 is currently some...

Duration:00:06:02

When Push Comes to Shove

10/1/2018
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Gaia, a galactic surveyor spacecraft, has caught our galaxy doing “the wave!” Studies of one billion stars show a wave-like motion in the stars of our galaxy’s arms. According to galactic structure theory, this shouldn’t be happening but it is. Why? A near-collision with the Sagittarius dwarf galaxy 200 million to 1 billion years ago imparted a gravitational shove that started “the wave.” When the galaxies collide again, our Milky Way will consume or incorporate the dwarf, one of the ways...

Duration:00:06:26

Only Pluto Knows For Sure

9/17/2018
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A group of researchers, including the Principle Investigator for the New Horizons program, Alan Stern, have found that after a review of 200 years of science literature, in only one instance has the ‘clear its orbit’ requirement ever been used to define an object as a planet. Further, the new team recommends that the definition of an object as a planet be based on the formation of the object itself rather than the ‘subject-to-external-influences’ dynamics of its orbit. As the 2006 IAU...

Duration:00:05:42

Starstruck by Star Trek

9/11/2018
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52 years ago, the television show Star Trek premiered! It spawned a whole new approach to space exploration and had an impact on the world’s culture. NBC cancelled Star Trek in February 1969, 5 months before Apollo 11 landed on the moon. The successor to the highly successful Kepler planet-hunting satellite TESS (Transiting Exoplanet Survey Satellite) sent the first data down last week, with new observations sent down every 13.5 days. TESS was launched on April 18, has settled into orbit...

Duration:00:05:12

Galactic Two-Step

9/3/2018
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Our Milky Way is thought to have originally formed shortly after the birth of the universe, 13.5 billion years ago. Built from the first stars and star clusters, gas from the galactic halo also contributed to the formation of the galaxy. Multiple galactic mergers helped trigger new star formation over and over again. But a new study of the Milky Way’s composition led by astronomers from the Astronomical Institute at Tohoku University in Tokyo suggests that our galaxy stopped producing stars...

Duration:00:05:12

Listen to “Lune”

8/27/2018
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NASA Science Visualization Labs’ Ernie Wright has created a beautiful visual compliment to De Bussey’s classic piano composition, ‘Claire De Lune’. Using images from NASA Lunar Reconnaissance Orbiter, which has been orbiting and photographing the moon in close-up high resolution since 2009, Wright’s video matches stunning images of the moon’s surface in a smooth-flowing visual montage that both reinvigorates the music and shows the moon’s changing appearance over the course of a lunar...

Duration:00:06:30

On the Prowl for Planets

8/20/2018
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The successor to the highly successful Kepler planet-hunting satellite TESS (Transiting Exoplanet Survey Satellite) sent the first data down last week. TESS was launched April 18, and settled into orbit and sent its first data two weeks ago, a photo of near-Sun space containing 200,000 stars, many of which could be accompanied by at least one planet. Kepler looked at just one small region of sky; TESS will survey almost the entire sky, concentrating on about 20,000 stars where it’s expected...

Duration:00:05:38

Time to Start Spotting Sunspots

8/13/2018
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The current (approximately 11-year-long) Solar Cycle is about to come to an end. Several years of long stretches of days without sunspots (up to 125 days so far this year – 38 of the past 41 days have been spotless) indicate the imminent beginning of a new cycle. Crews have been selected for the first commercial craft test flights and missions – Seven men, 2 women will crew flights beginning next year, 2019. Most notable is Philadelphia native Chris Ferguson, commander of the last space...

Duration:00:07:39

A Plethora of Planets

7/31/2018
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Mars’ close approach is Tuesday, July 31. A large subglacial lake of (very salty) liquid water has been found on Mars. This conclusion was arrived at by a group of European researchers using a radar analysis method frequently applied on Earth to determine subglacial features, including the presence of subglacial lakes.

Duration:00:05:57

All in the Family

7/23/2018
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Scientists have discovered 12 more of Jupiter’s moons, bringing the planet’s total count to 79. There are 175 known moons in the solar system overall, including Earth’s, Mars (2), Jupiter (79), Saturn (53), Uranus (27), and Neptune (13).

Duration:00:06:28

Relive Those Thrilling Days of Yesteryear

7/17/2018
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Follow a replay of the NASA lunar exploration events from 49 years ago online. http://www.firstmenonthemoon.com/ replays the actual audio communications between ground control and the astronauts from about 15 minutes before landing. The playback is augmented with video tapes of what was seen by the astronauts as they descended to land. Three Americans left on this date and landed 4 days later on the 20th; they stayed about 21 hours, walked around for 3.5 hours, then left the next day,...

Duration:00:07:50

Reaching Ryugu

7/10/2018
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Japan’s Hayabusa 2 spacecraft arrives at asteroid Ryugu on Wednesday, beginning a string of encounters including fly-bys, landings (3 rovers and a lander!!), sample acquisition and Earth return. Hayabusa 2 left Earth in 2014 and traveled 180 million miles to catch the 3,000 foot wide asteroid. This object is a member of the carbon-rich C-type asteroid family. Scientists believe these objects contain material that has remained undisturbed since the formation of the solar system. Thus, it’s...

Duration:00:07:22

Celebrating the 3rd, 4th, and 5th of July

7/2/2018
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Independence Day is sandwiched between the start of the dog days of summer and Aphelion. The dog days of summer are traditionally the 40 days beginning July 3 and ending August 11 (according to the Old Farmer’s Almanac), which coincide with the morning rise of the Dog Star, Sirius. Ancient Egyptians thought that the “combined heat” of Sirius and the Sun caused summer’s swelter. Thursday July 5th is Aphelion, when the Earth at its most distant point from the Sun for the year; 94,508,060...

Duration:00:07:17

Signs of Inflation

6/25/2018
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Dave Heller and Derrick Pitts, chief astronomer at the Franklin Institute, discuss efforts to peer all the way back in time and space with: They are in Philadelphia for a meeting at the University of Pennsylvania with the Simons Observatory regarding the Atacama Cosmology Telescope. Image:CC BY-SA 4.0

Duration:00:13:05

The Summer Solstice Beckons

6/4/2018
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Daylight lasts 14 hours and 52 minutes now, and the rate at which we’re gaining daylight is slowing dramatically. The rate at which we gain daylight slows about 3 seconds per day so by the 21st, we’re at zero gain. The mechanics? We’re slowly coming to a point in our solar orbit where the North pole of Earth has its greatest degree of tilt toward the sun. This gives Northern hemisphere-dwellers our ‘longest’ day because the sun’s path travels its longest arc across the sky. On that day, the...

Duration:00:04:42