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- Lunar Eclipse Beckons
Despite the forecasted blast of arctic air heading our way Sunday – bundle up and brave the cold because the next opportunity to take in a spectacular full lunar eclipse won’t come until May 2022 !
Spanning late Sunday into early Monday – this will be the first time since 1975 that a total lunar eclipse coincides with a holiday weekend. The period of totality when Earth’s shadow blocks out the moon extends from 11:41pm Sunday until 12:43am Monday. Derrick explains why this eclipse is popularly (but inaccurately) referred to as “the blood moon” and “the super moon.” If cloud cover blocks the spectacle, Exploratorium.edu will webcast the event from Northern California.Cotton is growing on the Moon . . albeit, inside the Chinese lander Chang’e 4. This marks the first time that seeds have sprouted on another world. Unfortunately, fluctuating temperatures caused the cotton sprout to quickly die.
In addition to Sunday’s Lunar Eclipse, this week also features a great opportunity to take in Winter Circle of constellations and bright stars.
Also, Venus slides past Jupiter in the pre-dawn sky this week.Mars can be spotted in the southwest sky every clear evening after sunset.7 min - Speed Kills
The more scientists learn about black holes, the more the findings confirm the warning: Speed kills.
The black hole ASASSN-14li lies at the heart of a galaxy 290 million light-years away from Earth and harbors between 1 million and 10 million times the mass of the sun. That makes it about as hefty as the black hole at our Milky Way galaxy’s core, known as Sagittarius A*, which contains about 4 million solar masses.Focusing on ASASSN-14li, astronomers at MIT just announced a new way to measure the rotation of black holes: Look for the remnants of partially consumed stars as regular pulses of x-rays as the star spins around with the black hole’s spin.In this case, the ‘pulse’ recurred every 131 seconds for 450 days; and with that, it was determined that the black hole spins at 50% of the speed of light (186,000 miles / second).More info here.A new study confirms an earlier claim that the cores of white dwarf stars eventually crystallize as they cool. Crystallization as a diamond comes because the core of many white dwarf stars is composed on oxygen and carbon, the essential ingredients in diamond composition. The thinking is that as the core cools below 18 million degrees, the crystallization begins converting the core into solid oxygen and carbon or diamond. Thinking about staking a claim? Good luck! These stars are very dim, not to mention their distance and the logistics involved in an attempt to mine something like this. But wait, there’s hope: Our sun is predicted to go diamond in about 10 billion years.Clear dark sky highlights: Venus and Jupiter dominate the pre-dawn sky this coming week. Mars and the moon are next to each other tonight.
8 min - Ultima Thule
NASA’s New Horizons spacecraft continues its sojourn through the outer reaches of our solar system. For the next 20 months, it will transmit data back to earth gathered from its passby of the planetessimal Ultima Thule, a snowman-shaped object around 20 miles in length. At a distance of 4.1 billion miles from Earth, it takes more than six hours (traveling at the speed of light) for that information to reach us.
Ultima Thule resides in the center of the vast Kuiper Belt, home to frozen remnants from the birth of the solar system.NASA launched the nuclear-powered spacecraft 13 years ago, and traveling at 32,000 miles per hour, it will take New Horizons an additional eight or nine years to bid adieu to the Kuiper Belt and enter interstellar space.At one billion miles beyond Pluto (visited by New Horizons in 2015), this marks the most distant flyby of an object in our solar system.Nancy Grace Roman, NASA’s first chief of astronomy and first leader of the effort to create Hubble Space Telescope died last week at the age of 93. She embarked on her career at NASA in 1948.
Turning to the night sky: A New Moon today means optimal viewing this week if the cloud cover cooperates;
Venus and Jupiter can be seen from 6:00a – 6:30a, Mars is available in the evening sky.Wednesday morning at 6:11, International Space Station pops into view in the North/Northwest and sails across the Northern sky into the East by 6:16am.The next morning (Thursday) at 5:21, NE, ISS can first be spied in the North East, and sails out to the east just under the brilliant star VEGA, then on to the South East horizon by 5:25am.8 min - Going, Going, Gone
Enjoy them while you can, because according to a new analysis of data from the Keck 10 meter telescope at Mauna Kea, Saturn’s rings are eroding away. Data gathered 10 years ago by Voyager space probes indicated that the water ice particles that make up Saturn’s ring system were being pulled out of the rings and spiraling down magnetic field lines from the inner edge of the rings to the planet. Given how quickly the rings seem to be deteriorating, the rings probably haven’t been around more than 100 million years.
Think of it this way; the dinosaurs only got to see the rings for around the first 35 million of those 100 million years before they died out.50 years ago astronauts Jim Lovell, Frank Borman, and Bill Anders left Earth on Apollo 8 for their historic circumnavigation of the moon. With that, they became the first humans to enter the gravitational sphere of influence of another celestial body. Not only was the mission the most important precursor to the first human landing just seven months later, but it was also the mission that gave us on Earth the most riveting view and most thorough definition of our ‘Spaceship Earth’ via the now iconic ‘Earthrise’ image. The crew orbited the Moon ten times over the course of 20 hours, during which they made a Christmas Eve television broadcast in which they read the first ten verses from the Book of Genesis. At the time, the broadcast was the most watched TV program ever.
Given the dearth of daylight during this solstice season, there is plenty to be seen overhead: In the pre-dawn sky, from 6:00a – 6:30a, Venus, Jupiter, Mercury. Then after sunset – Mars can be spotted in the southwest.
9 min - Adieu to Voyager 2
41 years since it left Earth in the rear view mirror, NASA’s Voyager 2 bids adieu to our solar system. Earlier this week, engineers monitoring transmissions detected a significant drop-off in solar wind buffeting the spacecraft and a dramatic increase in the cosmic ray count – clear indicators that Voyager 2 has stepped off into interstellar space.
It is now traveling at 34,000 mph, and at some 11 billion miles away, it takes sixteen and a half hours to transmit back to earth. Its next destination is 40,000 years away, but as the science instruments are turned off to conserve energy, we’ll lose communications and a fix on the probe’s location by the 2030s. Only the biggest radio receiver dishes in Australia can hear the spacecraft now.Winter Solstice is next Friday, when, at 5:23pm, Earth’s north rotational axis will have its greatest degree of tilt away from the sun.
Monday is the 115th anniversary of the Wright Brothers’ first powered flight.
On that day there were four flights. The first lasted just 12 seconds flying only 120 feet; the last flight of the day flew 852 feet over 59 seconds.8 min - Shedding Light on the Dark Side of the Moon
China’s next lunar visitor Chang’e 4 is due to touch down on the far side of the moon on December 31st. If it succeeds in that endeavor, it will be the world’s first lunar probe to make a soft landing on the side of the moon that always faces away from earth.The lander and rover are equipped with cameras, radar and spectrometers to help identify rocks and dirt in the area. The instruments will probe the structure of the rocks beneath the spacecraft, and assess the effects of the solar wind striking the lunar surface.
Since radio signals from earth are blocked from reaching the side of the moon that never faces us, the Chinese launched a satellite in May that is orbiting the moon, and will relay messages between Earth and Chang’e-4.Earthlings last walked on the moon 46 years ago this month; NASA’s Apollo 17 landed on the moon on December 11, 1972. Gene Cernan, the last person to walk on the moon and Harrison Schmidt, the only scientist to make it to the moon in the Apollo program spent more time on the lunar surface than anyone ever. They participated in three seven-hour-long moon walks – covering 22 miles!
Turning to night sky highlights this week: Venus in the predawn sky looks fabulous. It was right below the moon on Dec. 3rd – you may have seen the pair together. The next opportunity comes on January 1st and 2nd. In the meantime, an easier planet-Moon alignment occurs this Friday – it’ll be Mars and the Moon as the sun sets.
You’re watching the moon as it slides through our sky on its monthly journey around the earth.7 min - Early Sunsets in Early December
Starting on Monday, December 3rd, we’ll embark on a ten-day period when sunset arrives around 4:35 in the afternoon, marking the earliest sunsets of the year. Sunsets will commence a little later by Friday, December 21st – Winter Solstice – the day distinguished by the least amount of daylight.
The latest sunrise doesn’t take place until January 10th and then, thoughts and hopes can turn to Spring!Mars still dominates the Southern sky after sunset, Saturn barely hanging on.The Moon catches up with bright Venus on Monday morning between 4 a.m. and 6:15 a.m.November 30th was the 62nd anniversary of the only recorded instance of a human injury caused by a meteor.
It was 1956 when a meteor crashed through the ceiling of a room where Ann Hodges was sitting on a couch in Sylacauga, Alabama. The softball-sized object banged around the room and struck her on her leg, causing a bruise. The biggest related question cosmologists have now is whether it’s possible that microbes beyond earth seeded life here. Panspermia is the idea that there’s life throughout the universe; transpermia is the concept that microbes hitch rides on asteroids and meteoroids traveling throughout the cosmos.7 min - NASA Touchdown On Mars
NASA’s InSight Lander is scheduled to set down on the surface of Mars on Monday, November 26th. As a fixed station, InSight will drill a probe 5 meters down into the rock to both temperature profile that part of the rock column and to listen very carefully for seismic activity the lander can use to characterize the interior of the planet. The goal of this project is to learn more about the formation and evolution of terrestrial planets, including Mars, by learning about the physical composition and tectonic activity of the planet.
NASA celebrated the 20th anniversary of the International Space Station this week. It was Nov 20th 1998, when the first component was launched.
The ISS has been continuously occupied since Nov. 2, 2000. Current plans call for its continued operation through 2024.For the first time, astronomers have detected that a possible gamma ray bath could come from a supernova candidate in our galaxy. This particular star, named Apep after the monstrous serpent deity and mortal enemy of the Egyptian sun god Ra, isn’t the only star ready to blow.
There are approximately 20 other stars within 8,000 light years that are in their final stages of evolution and are large enough to go supernova.10 min - Hidden In Plain Sight
Our Milky Way has two very well known galactic companions: The Large and the Small Magellanic Clouds, irregular-shaped galaxies both about 170,00 light years from Earth. Both are visible to the naked eye in the southern sky.
The European Space Agency’s GAIA Space mapping satellite has detected another attendant galaxy hiding behind the Milky Way’s disc: The newly named “Antlia 2” is 1/3rd the size of our Milky Way itself. Determination of its mass indicates it is unusually light for a galaxy of its size.Researchers are suggesting that it is so because Antlia 2 is being slowly taken apart by galactic tides of our Milky Way Galaxy, even though it doesn’t come much closer than 130,000 light years away. We haven’t seen it before because of where it’s placed and because it’s 10,000 times dimmer than LMC, sort of like a ‘ghost’ galaxy.That means either it’s far too large for the amount of energy it gives out or far too dim for its size.The 2nd closest star to Earth Barnard’s Star is just six light years away (about 2 light years farther than Proxima Centauri – our nearest celestial neighbor).
Astronomers have confirmed the existence of a planet three times the mass of Earth, 40 million miles from its low-mass red dwarf sun, with a surface temperature of 275 degrees below zero.According to NASA, the current number of confirmed exoplanets: 3,838.7 min - Going in Circles
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 touching and could explode as a nova sometime in a few thousand years.The annual Leonid Meteor Shower peaks on the 17th this year – although the anticipated 20 meteors/hour is not especially impressive this year.
6 min
About Skytalk
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A weekly discussion of what’s new and interesting in astronomy with Dr. Derrick Pitts