Moonstruck ?

“A Note About Sky Phenomena
The known universe has been around 14 billion years — Earth 4.5 billion years. If we’re lucky, we live 100 years. When anything happens in the sky while you are alive, it is not likely rare in the cosmos. It’s not even likely rare in your lifetime. But our collective urge to think so is strong. This state of mind exists deep within us, and drives all urges to believe that our fate lies in the stars and not within ourselves.

Further, there can be events in your life that don’t repeat for hundreds or even thousands of years. But those tend to be categories of events that repeat hundreds, even thousands of times in your life. For example, the precise configuration of all eight planets in this moment will not repeat for nearly 150,000 years. But the same is true for yesterday’s configuration of planets. And tomorrow’s configuration of planets.

So it’s possible for an event to be rare, but wholly uninteresting.

A Note About the Moon
“Blue” moons (the second full moon in a calendar month) occur, on average, every two and a half to three years. An event more frequent than the Summer Olympics. But nobody ever declares “Watch out for a rare Olympics coming up!”

Total Lunar Eclipses are more frequent than that, occurring, on average, once every two years or so. Some years have two. More frequent than any Olympics at all. Occasionally, the eclipsed Moon will take on a deep red-Rose color from sunlight filtering through Earth’s atmosphere that disperses into Earth’s shadow on the darkened full Moon. Note that our collective morbid mindsets have embraced the term “Blood Moon” instead.

Once every lunar month the Moon is at perigee — the closest to Earth in the Moon’s oval orbit. Perigee coincides with the day of a Full moon about once every 30 months — 2.5 years. Some people who are adjective-challenged call this a “super moon”. Even though a such a moon is only 1% bigger than the full Moon that follows it a month later.

On January 31, 2018, all three events occur on the same calendar day: Blue Moon, Lunar Eclipse, Perigee. You get that every fifteen years or so on average. Although many time zones on Earth (all of Australia and New Zealand included) will not enjoy the Blue Moon since they will instead experience the Perigee Eclipse on calendar day February 1st.

For observing details on the Lunar Eclipse ( the only event of any real astronomical significance on January 31 ) I now, and often reference the Earth & Sky website.

As Always, keep looking up.” -Neil deGrasse Tyson, New York City

RCW 114: A Dragon’s Heart in Ara

Image Credit & Copyright: Andrew Campbell

2018 January 11

RCW 114: A Dragon’s Heart in Ara
Explanation: Large and dramatically shaped, this cosmic cloud spans nearly 7 degrees or 14 full moons across planet Earth’s sky toward the southern constellation Ara. Difficult to image, the filamentary apparition is cataloged as RCW 114 and traced in this telescopic mosaic by the telltale reddish emission of ionized hydrogen atoms. In fact, RCW 114 has been recognized as a supernova remnant. Its extensive filaments of emission are produced as the still expanding shockwave from the death explosion of a massive star sweeps up the surrounding interstellar medium. Consistent estimates place its distance at over 600 light-years, indicating a diameter of about 100 light-years or so. Light from the supernova explosion that created RCW 114 would have reached Earth around 20,000 years ago. A neutron star or pulsar has recently been identified as the collapsed remains of the stellar core.

Source: Astronomy Picture of the Day

Today is Dark Matter Day

2017 October 31

Dark Matter in a Simulated Universe 
Illustration Credit & Copyright Tom Abel & Ralf Kaehler (KIPACSLAC), AMNH

Explanation: Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters so fast, why gravitational lenses so strongly deflect light, and why visible matter is distributed as it is both in the local universe and on the cosmic microwave background. The featured image from the American Museum of Natural History’s Hayden Planetarium Space Show Dark Universe highlights one example of how pervasive dark matter might haunt our universe. In this frame from a detailed computer simulation, complex filaments of dark matter, shown in black, are strewn about the universe like spider webs, while the relatively rare clumps of familiar baryonic matter are colored orange. These simulations are good statistical matches to astronomical observations. In what is perhaps a scarier turn of events, dark matter — although quite strange and in an unknown form — is no longer thought to be the strangest source of gravity in the universe. That honor now falls todark energy, a more uniform source of repulsive gravity that seems to now dominate the expansion of the entire universe.

Source: Astronomy Picture of the Day

Cassini’s Grand Finale

NASA’s Cassini spacecraft (launched in 1997) has been in orbit around Saturn since 2004 exploring the giant planet, its spectacular system of rings and moons. Cassini was also carrying with it the European Huygens Probe which was dispatched after arrival and successfully landed on the moon Titan, becoming the first human made craft to land on a surface in the outer solar system.

In 2017 – after more than a decade of bringing home remarkably successful scientific achievements, discoveries and a treasury of gorgeous photos – the spacecraft is running out of fuel to maneuver. In order to protect the moons Enceladus and Titan, and their potentially life-bearing sub surface oceans, from possible contamination in the unlikely event of a future collision, it has been decided to take Cassini permanently out of service. This is done by crashing the spacecraft into the atmosphere of Saturn – but not without doing some amazing science on the way.

22 times, Cassini dives through previously unexplored gap between Saturn and its rings, collecting new data on the mass of the rings (used to help determine their age), measurements of Saturn’s gravity and magnetic fields (used to help understanding its internal structure) and sending home stunning views of Saturn’s clouds and the rings – seen from a closer range than ever before.

Even up until the very end, Cassini will bring home data, as it tastes the atmosphere of Saturn, just minutes before burning up and becoming part of the planet itself.

Lees meer:

Astronomy Picture of the Day

Clouds of Andromeda
Image Credit & Copyright: Rogelio Bernal Andreo (Deep Sky Colors)

Explanation: The beautiful Andromeda Galaxy is often imaged by planet Earth-based astronomers. Also known as M31, the nearest large spiral galaxy is a familiar sight with dark dust lanes, bright yellowish core, andspiral arms traced by blue starlight. A mosaic of well-exposed broad and narrow-band image data, this colorful, premier portrait of our neighboring island universe offers strikingly unfamiliar features though, faint reddish clouds of glowing ionized hydrogen gas in the same wide field of view. Still, the ionized hydrogen clouds likely lie in the foreground of the scene, well within our Milky Way Galaxy. They could be associated with the pervasive, dusty interstellar cirrus clouds scattered hundreds of light-years above our own galactic plane. If they were located at the 2.5 million light-year distance of the Andromeda Galaxy they would be enormous, since the Andromeda Galaxy itself is 200,000 or so light-years across.

The Bubble Nebula

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2016 April 22


NGC 7635: The Bubble Nebula
Image Credit: NASA, ESA, Hubble Heritage Team (STScI / AURA)

Explanation: Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 7 light-year diameter bubble offers evidence of violent processes at work. Above and left of the Bubble’s center is a hot, O-type star, several hundred thousand times more luminous and around 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula and associated cloud complex lie a mere 7,100 light-years away toward the boastful constellation Cassiopeia. This sharp, tantalizing view of the cosmic bubble is a composite of Hubble Space Telescope image data from 2016, released to celebrate the 26th anniversary of Hubble’s launch.

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCPNASA Official: Phillip Newman Specific rights applyNASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2015 December 6


A Force from Empty Space: The Casimir Effect
Image Credit & Copyright: Umar Mohideen (U. California at Riverside)

Explanation: This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energyfluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for its discoverer, who, 55 years ago, was trying to understand why fluids like mayonnaise move so slowly. Today, evidence indicates that most of the energy density in the universe is in an unknown form dubbed dark energy. The form and genesis of dark energy is almost completely unknown, but postulated as related to vacuum fluctuations similar to the Casimir Effect but generated somehow by space itself. This vast and mysterious dark energy appears to gravitationally repel all matter and hence will likely cause the universe to expand forever. Understanding vacuum energy is on the forefront of research not only to better understand our universe but also for stopping micro-mechanical machine parts from sticking together.

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights applyNASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC & Michigan Tech. U.

Seven Brief Lessons on Physics


I believe that our species will not last long. It does not seem to be made of the stuff that has allowed the turtle, for example to continue to exist more or less unchanged for hundreds of millions of years; for hundreds of times longer, that is, than we have even been in existence. We belong to a short-lived genus of species. All of our cousins are already extinct. What’s more, we do damage. There are frontiers where we are learning, and our desire for knowledge burns. They are in the most minute reaches of the fabric of space, at the origins of the cosmos, in the nature of time, in the phenomenon of black holes, and in the workings of our own thought processes. Here, on the edge of what we know, in contact with the ocean of the unknown, shines the mystery and the beauty of the world. And it’s breathtaking. – Carlo Rovelli


I can’t believe it’s not butter

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2015 September 18


A Plutonian Landscape
Image Credit: NASA, Johns Hopkins Univ./APL, Southwest Research Institute

Explanation: This shadowy landscape of majestic mountains and icy plains stretches toward the horizon of a small, distant world. It was captured from a range of about 18,000 kilometers whenNew Horizons looked back toward Pluto, 15 minutes after the spacecraft’s closest approach on July 14. The dramatic, low-angle, near-twilight scene follows rugged mountains still popularly known as Norgay Montes from foreground left, and Hillary Montes along the horizon, giving way to smooth Sputnik Planum at right. Layers of Pluto’s tenuous atmosphere are also revealed in the backlit view. With a strangely familiar appearance, the frigid terrain likely includes ices of nitrogen and carbon monoxide with water-ice mountains rising up to 3,500 meters (11,000 feet). That’s comparable in height to the majestic mountains of planet Earth. This Plutonian landscape is 380 kilometers (230 miles) across.

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights applyNASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC & Michigan Tech. U.