Skytalk

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A weekly discussion of whats new and interesting in astronomy with Dr. Derrick Pitts

Episódios

  • Cold Snap Up North

    Cold Snap Up North

    29/02/2020 Duração: 06min

    NASA’s InSight Mars lander keeps daily records of weather conditions at the Elysium Planitia landing site on the red planet. Last week saw daytime highs from 8 to 15 degrees Fahrenheit; lows fell to -139 degrees. Seasons are twice as long on Mars as on Earth because the Martian year is 687 days; almost double an Earth year. Mars doesn’t have months like we have months though. Our concept is based on a lunar orbit. Mars’ moons orbit much faster – Phobos every 8 hours, Deimos every 30 hours; so well over 2,000 orbits per 30 day ‘month’ for Phobos and over 500 orbits per ‘month’ for Deimos. InSight landed Nov. 2018 on a two-year mission to better understand the interior of Mars using both surface and drilling geophysical sensors. Turning to night sky highlights this week: Mars, Jupiter, and Saturn have the morning sky at 6:00 a.m.; Venus has the evening at 6:00 p.m. We’re gaining 2.5 minutes of sunlight per day through March.

  • Older than Dirt

    Older than Dirt

    22/02/2020 Duração: 08min

    Stardust discovered in a meteorite that landed in Australia more than 50 years ago is up to three billion years older than our solar system. These remnants are left over from ancient stars that populated this region of the galaxy prior to the birth of our sun, some 4.5 billion years ago. These particles got swept up in planet formation and/or hitched a ride to Earth on asteroids that have been in circulation ever since. Dating was determined from an element, Neon-21, which is derivative of cosmic ray-bombarded silicon carbide. Higher proportion of Neon-21 indicates the silicon carbide was drifting in space for a very long time before being embedded in a hunk of our solar system’s detritus left over after the solar system formed. The discovery may yield new insight into star formation in the Milky Way. Turning to the night sky – Mars, Jupiter, and Saturn are still aligned in the 6:00 am predawn sky in the east. They’re sliding closer together over the next few weeks. Venus till dominates the southwest ev

  • Taking a Telescope to Galileo

    Taking a Telescope to Galileo

    15/02/2020 Duração: 10min

    Today is Galileo’s 456th birth anniversary. His iconoclastic reputation overshadows his basic raison d’etre at the time – to make a buck. He was a struggling teacher who worked in the ‘gig economy’ of Renaissance Italy. Galileo wasn’t born to a high place in society; he wasn’t a politician, his parents were not rich and his father actually wanted his son to become a physician. He really wanted to be a mathematician. He eventually ditched medical school and became a university math instructor where he began to investigate physics of motion. A colleague informed him of a new optic device he’d seen. After a bit of research, Galileo figured out how others were making these new optic devices and using his math skills, made a better one. He immediately saw the how this invention could get him hired by a wealthy and influential patron to whom he sold the manufacturing rights. He got a better university appointment and didn’t have to teach classes, so he could pursue his research interests. Fast Radio Bursts, or FRB

  • Coming Attractions

    Coming Attractions

    08/02/2020 Duração: 07min

    Astronomers observing white dwarf stars see spectrographic signatures of previously orbiting gas giant planets. Our gas giants (Jupiter and Saturn) will possibly do the same – leave signatures of their existence on our White Dwarf sun long after all the inner planets are gone and the outer planets are transformed. Not to worry – this won’t happen for some eight billion years. Bid adieu to the Spitzer Space Telescope! Named after astrophysicist Lyman Spitzer (in 1965 he first proposed what would later become the Hubble Space Telescope), the Spitzer Space Telescope was launched in 2003. Expected to last just 2.5 years, Spitzer continued generating good science results until it was finally turned off last month (after it ran out of coolant), an amazing 16 years after it launched. Dusty stellar nurseries, extrasolar planets, centers of galaxies, and newly forming planetary systems hidden behind thick curtains of cosmic dust would remain unseen without Spitzer’s unique heat-detecting capability.

  • 49ers, Chiefs  Punxsutawney Phil

    49ers, Chiefs & Punxsutawney Phil

    01/02/2020 Duração: 05min

    49ers, Chiefs & Punxsutawney Phil This Superbowl Sunday coincides with Groundhog Day – the first cross-quarter day of 2020 (half-way between winter and spring). Punxsutawney Phil may be the most famous groundhog in the U.S., but he isn’t the most accurate. The four-legged creature only has a 39 percent accuracy, according to Stormfax Almanac’s data. Phil sees his shadow about 85 percent of the time (which portends six more weeks of winter) Extreme Global Warming! – Different process altogether from Earth. KELT-9b is a gas giant planet orbiting a star 670 light years away from earth. As a ‘hot Jupiter’, it orbits so close to its sun, it’s temperature is very very high. How high? Highest ever recorded for a planet – 7800 degrees Fahrenheit! So high that molecules of Hydrogen gas are torn apart; they can recombine on the night side of the planet. A year is 1.5 days, tidally locked so one side NEVER sees daylight. Weird, right? The Night Sky Our own gas gian

  • Our Stellar Neighbor Beckons

    Our Stellar Neighbor Beckons

    21/01/2020 Duração: 09min

    The dim red star Proxima Centauri, 4.2 lightyears from Earth, is known to have an EarthPlus-planet in the star’s habitable zone. Now a second planet has been detected, but this one is 5.8 times the mass of our planet and orbits its star only once every five years. Unfortunately, it’s also too far from the cool star to be warm enough for liquid water. So, it’s not habitable – at least for us. Which leads to a proposal to send 1,000 tiny spacecraft – really just a computer chip attached to a solar sail driven by ground-based lasers with 100 gigawatts of power to drive them along. The idea is that the tiny chips, with so little mass, could be driven up to 15-20% of the speed of light, making the 4.2 light year trip in just 20-30 years. Initial funding of $100 million comes from Russian Yuri Milner, backed by Mark Zuckerberg and Stephen Hawking. –When totaling up all the matter in the universe, cosmologists believe that about 80% of the mass of the universe is completely unseen dark matter, 21% is dar

  • Elementary

    Elementary

    11/01/2020 Duração: 05min

    Supernovae are known as element factories, but astronomers are now discovering that merging neutron stars and fast-spinning supernovae may also be capable of creating variants of the elements heavier than iron. Heavy elements are created through nuclear fusion. Venus shines in the west after sunset. Mars brightens up the east at 6:00am for sunrise, now sliding towards Antares of Scorpius. Good opportunity to compare the two. Could the concept of ‘dark energy’ all be a big mistake? Next week, Skytalk examines new data showing that the key assumption made in the discovery of dark energy is in error.

  • Imaging the Unimaginable

    Imaging the Unimaginable

    28/12/2019 Duração: 07min

    This year’s highlights in the world of astronomy include: 1) An image of the shadow of a black hole resembles an ‘orange doughnut.’ A supermassive Black Hole was seen in silhouette against the background of its surrounding accretion disk. 2) Liquid water is identified at Saturn’s moon Enceladus. 3) The New Horizons spacecraft flew past Pluto in 2016, then flew past an even more distant object on New Year’s Day 2019 – a double-lobed Kuiper Belt object now known as Arrokoth. Its shape resembles the BB-8 droid from the recent ‘Star Wars’ chapters. It features a small circle atop a larger circle, except it’s flattened. Assessing the night sky: Venus and the Moon are visible tonight in the southwest just after sunset.

  • Mark the Moment

    Mark the Moment

    23/12/2019 Duração: 02min

    We’ve arrived at the point in our solar orbit where the number of hours of sunlight are at a minimum for us in the North, and and conversely at a maximum for those in the Southern hemisphere. Sunset is already three minutes later than its earliest time, but we’re still losing time at sunrise, and the latest sunrise doesn’t come until early January. Hanukkah begins tomorrow at sunset, Christmas Day is Wednesday, and the first day of Kwanzaa is Thursday the 26th. The Moon and Mars can be seen in the December 23 predawn sky at 6:20 am, and Venus is swiftly pulling away from sinking Saturn in the Southwest at 5:15 pm.

  • Let There Be Light (but not too much)

    Let There Be Light (but not too much)

    14/12/2019 Duração: 06min

    SpaceX will coat one side of a satellite to reduce brightness interference when observing from Earth. They intend to test one unit on the next deployment. There will be thousands of Starlink satellites joining the already tens of thousands of pieces of space junk. We need to develop a plan to clean up and fast! The European Space Agency will test a ‘space grab’ tech to start to clean up space. ‘Clear Space-1’ is designed to reach a dead satellite, grab it, and drag it down into a fiery re-entry destruction. So it’s slow and expensive, but it’s an emerging business as the future will certainly see an enormous increase in satellites. Anniversaries of note: 116 years ago on Tuesday, December 17, 1903, the first powered flight by Orville Wright, although it only traveled 12 feet. On this date in 1972, Apollo 17’s Gene Cernan becomes the last human to walk on the moon. It was just 66 years from the Wright brothers first powered flight to the last human on the moon!

  • Worth A Look

    Worth A Look

    09/12/2019 Duração: 08min

    Thinking about buying a telescope as a gift this holiday season? Consider these three easy guidelines: 1) Start simple; a telescope that is easy to use will get used more often. 2) Don’t buy a telescope based on the supposed magnification. Instead, go for the largest aperture you can afford, while also considering portability. You may want to transport your telescope to an area with darker skies. How big and heavy a telescope are you willing to carry? 3) Consider a refractor versus a reflector: One uses lenses, the other uses mirrors to gather light from dim objects and create an image that is then magnified by the eyepiece. Typically, you can get a ‘bigger’ reflector scope (larger aperture) than a refractor scope for the same price. Refractors are better for “low surface brightness” objects such as nebulae, galaxies, and comets and refractors are better for pinpoint light sources such as stars, planets, or the moon. For more details, check out Derrick Pitts’s tips for purc

  • Water, Water Everywhere

    Water, Water Everywhere

    02/12/2019 Duração: 05min

    There are lots of hints regarding the possibility of the existence of liquid water around the solar, system, the galaxy, and the universe, but confirmation at only a very few places: Mars and the moon for example. Astronomers using Keck telescopes at Mauna Kea Observatory in Hawaii now confirm the existence of liquid water at Jupiter’s moon Europa. Under Europa’s ice crust, there could be a subsurface ocean containing as much as twice the amount of water as Earth’s oceans. These newest observations directly detected water vapor (5200 lbs or 650 gallons) issuing from fissures in Europa’s ice-crusted surface. Researchers have been speculating about water on Europa since 1993. The galaxy NGC 6240 is shown to contain three supermassive black holes at its core. This indicates a triple collision of galaxies back in the dark past of the universe. Each black hole appears to measure 90 million solar masses, in a space 3,000 light years wide. Wolfram Kolatschny at the University of Göttingen s

  • You’re Outta Here!

    You’re Outta Here!

    23/11/2019 Duração: 05min

    Our Milky Way’s SgrA Black Hole in the center of our galaxy has ejected a star from the galaxy at a brisk 3.7 million miles per hour. The star originally was part of a binary system, but when the pair got too close to SgrA, the companion was swallowed, and this one was thrown out some five million years ago. This star (S5-HVS1) is unique because of its high velocity and close passage to us; a mere 29,000 light years. The star is currently seen in the southern constellation Grus and is moving 10 times faster than most Milky Way stars. Remember the excitement when increased methane levels in the Martian atmosphere triggered speculation about burping cows on Mars? Now researchers are seeing increased levels of oxygen. Curiosity Rover’s atmospheric analysis device has been collecting data on the composition of the Martian atmosphere since it arrived three years ago. One thing it found is that the amount of oxygen in the atmosphere varies seasonally, with swings in the overall amount (measured at Gale

  • What’s in a Name?

    What’s in a Name?

    16/11/2019 Duração: 05min

    Following its Pluto encounter in 2015, NASA’s New Horizons spacecraft was pushing on into the Kuiper Belt, aiming toward an object known originally as 2014 MU69, when space scientists and the public decided it needed a new name. Shortly before the New Horizons encounter on January 1, 2019, they chose the name Ultima Thule. Then a reporter at Newsweek pointed out that the Nazi party had used the phrase Ultima Thule to refer to the mythical homeland of the Aryan people. The term apparently remains in use by modern so-called alt-right groups. Now the object has a new name yet again. The name is now Arrokoth, which means sky in the Powhatan and Algonquian languages. The name was chosen based on the local Native American culture in Maryland, where the New Horizons mission control center is based. Arrokoth is roughly 19 miles long, or about 1/60th the diameter of Pluto. A wealth of data from New Horizons’ encounter with Arrokoth is still being sent back from the spacecraft to Earth for analysis. Scientists us

  • Happy Birthday, Carl!

    Happy Birthday, Carl!

    09/11/2019 Duração: 07min

    November 9th marks the anniversary of legendary astronomer Carl Sagan’s birth. Sagan was known for his wonderfully poetic way of explaining and transporting listeners into the history and complexities of the universe. He explored the mysteries of outer space in his landmark PBS program, “Cosmos: A Personal Voyage.” Monday is Mercury Transit Day: The planet Mercury will cross between Earth and the Sun. The transit starts at 7:36 am EST and ends at 1:04 pm. Those hoping to witness the transit must ensure they have proper eye protection. Alternatively, head to the Franklin Institute to watch through their telescopes. It happens about 13 times per century – and the next opportunity comes in the year 2032. It can’t happen on every orbit because Mercury’s orbit is tilted slightly from Earth’s. That means our orbits align only twice a year, so only during those times can Venus and Mercury be seen crossing the sun’s disk in transit. Sizing Up Dwarf Planets: Hygeia, whi

  • Special Delivery

    Special Delivery

    02/11/2019

    An International Space Station Resupply Mission is scheduled to launch from Wallops Island, Virginia, at the Mid-Atlantic Regional Spaceport (MARS). It will transport 8,200 lbs of research, crew supplies, and hardware to the six-person crew on the ISS. The craft arrives at ISS at 4:30 am on Monday. We bid adieu to Daylight Saving Time when we shift our clocks back one hour at 2:00 am on Sunday, November 3rd. Next – we mark the earliest sunset in early December. Take advantage of the earlier nightfall: Jupiter and Saturn are still available to be seen in the southwest after sunset, Venus rising out of the west as well. Mars has the pre-dawn sky now.

  • Matter Barely Matters

    Matter Barely Matters

    26/10/2019

    This Thursday is Halloween…and Dark Matter Day! Dark matter-themed events are being organized by labs and institutions around the world doing this research. They range from live webcasts with researchers to dark matter scavenger hunts to a Reddit AMA. Find a sortable list at www.darkmatterday.com/events-list Scientists believe that dark matter, which we have so far only detected through its gravity-based effects in space, makes up about a quarter (26.8 percent) of the total mass and energy of the universe, and something that is driving the universe’s accelerating expansion, which scientists call dark energy, accounts for another 68.3 percent. The ordinary matter, like stars and planets and galaxies, makes up just 4.9 percent of the total mass and energy of the universe. So there’s a BIG part of the universe that we don’t know much about. We’re not sure if dark matter is made up of undiscovered particles, or if it can be explained by tweaking the known laws of physics. Its makeup

  • Dinner on Mars?

    Dinner on Mars?

    19/10/2019

    A group of researchers at Wageningen University in the Netherlands have successfully grown edible food crops in soils that simulate the soil composition of the Moon and Mars. Garden cress, radish, spinach, quinoa, tomato, rye, chives, leek and peas were all harvested in this most recent study. Crops did better in the Martian soil than the lunar soil and spinach didn’t like either soil simulant. An earth soil ‘control’ was used. The most intriguing finding from the study is that common crops can grow in Moon/mars soils simulants augmented with a compost-like supplement. October 21st is the 96th anniversary of the first-ever planetarium show at the Deutches Museum in Munich, Germany. Fels Planetarium was the second planetarium to open in the United States in January 1934. October 22nd is the 4,155th anniversary of the first record of a solar eclipse. In China where prediction of eclipses for the legitimacy of the Emperor, according to legend, two court astronomers were beheaded because they

  • Keeping Score

    Keeping Score

    12/10/2019

    Saturn pulls ahead of Jupiter in the number of moons detected – current score: 82 to 79 Researchers recently announced the discovery of 20 new moons orbiting Saturn by using big telescopes at Hawaii’s Mauna Kea observatory equipped with very sensitive detectors. 17 of them orbit backwards, opposite the planet’s direction of rotation, and most of the new ones are about three miles in size. The current idea about their origin is that they are the detritus left over from the breakup of a moon not long after Saturn’s formation billions of years ago. When we think about all the energetic activity happening out there in the universe – supermassive black holes, millisecond pulsars, colliding neutron stars, exploding supernovae – it’s nice to know that in our little corner of the universe not much is happening, right? Hold your horses, because maybe we’re just in between happenings. Astronomers announced earlier this week that evidence has been detected that an enorm

  • Rocket Man

    Rocket Man

    05/10/2019

    Saturday, October 5th is the 132nd birth anniversary of rocket pioneer Robert H. Goddard. His was the first liquid-fueled rocket to prove the concept that allowed for the exploration of space as we know it today. He launched the first liquid-fueled rocket in March 1926. The maximum altitude he achieved was 1.7 miles. His technology eventually was adopted in America soon after his death in 1945. October 5th is also the 61st anniversary of the founding of NASA. It was originally established as the National Advisory Committee for Aeronautics, and had 8000 employees and three laboratories. President Dwight Eisenhower signed the National Aeronautics and Space Act in August 1958 in response to the launch of Sputnik on October 4th, 1957. Congress created the National Aeronautics and Space Administration on October 1st, 1958. Along with our seasonal weather change comes the now obvious changes in sun time. We’re down to 11 hours 36 minutes of sun above the horizon vs 15 hours on June 21. We’ll still lose