Rocket Transits Rippling Sun

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.

2022 May 31

The featured image shows a Falon 9 rocket transiting in front of the Sun in mid May. The heat from the rocket's exhaust makes the Sun's outline appear to ripple. Please see the explanation for more detailed information.

Rocket Transits Rippling Sun
Image Credit & Copyright: Michael Cain
Explanation: The launch of a rocket at sunrise can result in unusual but intriguing images that feature both the rocket and the Sun. Such was the case last month when a SpaceX Falcon 9 rocket blasted off from NASA’s Kennedy Space Center carrying 53 more Starlink satellites into low Earth orbit. In the featured launch picture, the rocket’s exhaust plume glows beyond its projection onto the distant Sun, the rocket itself appears oddly jagged, and the Sun’s lower edge shows peculiar drip-like ripples. The physical cause of all of these effects is pockets of relatively hot or rarefied air deflecting sunlight less strongly than pockets relatively cool or compressed air: refraction. Unaware of the Earthly show, active sunspot region 3014 — on the upper left — slowly crosses the Sun.


Tomorrow’s picture: unexpected meteors 

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

Apollo 16 Moon Panorama

Apollo 16 Moon Panorama
Image Credit: Apollo 16NASAPanorama Assembly: Mike Constantine

Explanation: Fifty years ago, April 20, 1972, Apollo 16’s lunar module Orion touched down on the Moon’s near side in the south-central Descartes Highlands. While astronaut Ken Mattingly orbited overhead in Casper the friendly command and service module the Orion brought John Young and Charles Duke to the lunar surface. The pair would spend nearly three days on the Moon. Constructed from images (AS16-117-18814 to AS16-117-18820) taken near the end of their third and final surface excursion this panoramic view puts the lunar module in the distance toward the left. Their electric lunar roving vehicle in the foreground, Duke is operating the camera while Young aims the high gain communications antenna skyward, toward planet Earth.


Another view (344)

Earth layers, computer artwork. The external layer shows the Earth’s surface topography and atmosphere, including land, water and clouds. This surface layer extends downwards for around 35 kilometres as the rocky crust. The mantle (red) is a viscous layer of rocks under high pressures and temperatures, extending downwards to a depth of around 2890 kilometres. The outer core (yellow) is a liquid layer of iron and nickel, around 2260 kilometres thick. The inner core (right) is a liquid sphere of a iron-nickel alloy, with a radius of 1220 kilometres., Image: 101651243, License: Rights-managed, Restrictions: , Model Release: no, Credit line: Profimedia, Sciencephoto RM

Moon Pairs and the Synodic Month

Image Credit & Copyright: Marcella Giulia Pace

Explanation: Observe the Moon each night and its visible sunlit portion will gradually change. In phases progressing from New Moon to Full Moon to New Moon again, a lunar cycle or synodic month is completed in about 29.5 days. They look full, but top left to bottom right these panels do show the range of lunar phases for a complete synodic month during August 2019 from Ragusa, Sicily, Italy, planet Earth. For this lunar cycle project the panels organize images of the lunar phases in pairs. Each individual image is paired with another image separated by about 15 days, or approximately half a synodic month. As a result the opposite sunlit portions complete the lunar disk and the shadow line at the boundary of lunar night and day, the terminator, steadily marches across the Moon’s familiar nearside.

Source: Astronomy Picture of the Day

Crescent Moon HDR

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. 2020 August 24

Made from 14 light frames by Starry Sky Stacker 1.3.1. Algorithm: Mean

Crescent Moon HDR
Image Credit & Copyright: Miguel Claro (TWANDark Sky Alqueva) (posted with permission)

Explanation: How come the crescent Moon doesn’t look like this? For one reason, because your eyes can’t simultaneously discern bright and dark regions like this. Called earthshine or the da Vinci glow, the unlit part of a crescent Moon is visible but usually hard to see because it is much dimmer than the sunlit arc. In our digital age, however, the differences in brightness can be artificially reduced. The featured image is actually a digital composite of 15 short exposures of the bright crescent, and 14 longer exposures of the dim remainder. The origin of the da Vinci glow, as explained by Leonardo da Vinci about 510 years ago, is sunlight reflected first by the Earth to the Moon, and then back from the Moon to the Earth.


The Chase for the Ghost Particle and the Secrets of the Universe

A sketch of the IceCube neutrino observatory ( J. Yang/NSF)

Neutrinos are elementary particles, just like electrons that buzz about atomic nuclei or quarks that combine to make protons and neutrons. They are fundamental building blocks of matter, but they don’t remain trapped inside atoms. Also unlike their subatomic cousins, neutrinos carry no electric charge, have a tiny mass, and hardly ever interact with other particles. A typical neutrino can travel through a light- year’s worth of lead without interacting with any atoms. Therein lies the snag: neutrinos are pathologically shy. Their severe reluctance to mingle makes these particles hard to pin down, so neutrino hunting is a tricky business. But every so often, a neutrino does collide with something, such as a proton inside a water molecule, essentially by accident. It is to raise the odds of accidental collisions, and thus to increase our chances of observing neutrinos, that scientists build extremely large detectors like IceCube

You still can’t see neutrinos directly, but you can get a whiff of their presence from the clues they leave behind. On the rare occasions that neutrinos do interact with matter, they produce charged particles such as muons that physicists can detect with their instruments. But distinguishing neutrino signals from unrelated “noise” poses a challenge: cosmic rays, fast- moving particles that arrive from deep space, also produce muons, which might be confused with muons produced by neutrino interactions. Neutrino hunters place their equipment deep underground, or under a thick layer of ice, so that cosmic ray muons cannot get through. As Janet Conrad of the Massachusetts Institute of Technology explains, “If you’re trying to listen to a whisper, you don’t want a lot of noise around.” -Ray Jayawardhana, The Neutrino Hunters

The Annotated Galactic Center

Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva)

Explanation: The center of our Milky Way galaxy can be found some 26,000 light-years away toward the constellation Sagittarius. Even on a dark night, you can’t really see it though. Gaze in that direction, and your sight-line is quickly obscured by intervening interstellar dust. In fact, dark dust clouds, glowing nebulae, and crowded starfieds are packed along the fertile galactic plane and central regions of our galaxy. This annotated view, a mosaic of dark sky images, highlights some favorites, particularly for small telescope or binocular equipped skygazers. The cropped version puts the direction to the galactic center on the far right. It identifies well-known Messier objects like the Lagoon nebula (M8), the Trifid (M20), star cloud M24, and some of E.E. Barnard’s dark markings on the sky. A full version extends the view to the right toward the constellation Scorpius, in all covering over 20 degrees across the center of the Milky Way.


Planetary Transit Time Chart

Image by Cathy Kinnaird

Source: Channels by Type 4 – Understanding the Transit Program

Except that we don’t use the 29.5 days synodic cycle in Human Design, but the 27.3 days tropical cycle.
See calculations here: Lunar Cycle Calculations

And Mercury and Venus are off too, the mistake is around the Wheel (Earth) vs around the Sun, improved here:


Video Credit: Data: Lunar Reconnaissance Orbiter ; Animation: NASA‘s Scientific Visualization Studio;
Music: The Blue Danube (Johann Strauss II)

Explanation: Our Moon’s appearance changes nightly. As the Moon orbits the Earth, the half illuminated by the Sun first becomes increasingly visible, then decreasingly visible. The featured video animates images taken by NASA’s Moon-orbiting Lunar Reconnaissance Orbiter to show all 12 lunations that appear this year, 2018. A single lunation describes one full cycle of our Moon, including all of its phases. A full lunation takes about 29.5 days, just under a month (moon-th). As each lunation progresses, sunlight reflects from the Moon at different angles, and so illuminates different features differently. During all of this, of course, the Moon always keeps the same face toward the Earth. What is less apparent night-to-night is that the Moon‘s apparent size changes slightly, and that a slight wobble called a libration occurs as the Moon progresses along its elliptical 


The East 96th Street Moon

Image Credit & Copyright: Stan Honda

 A very full Moon rose over Manhattan’s Upper Eastside on June 28, known to some as the Strawberry Moon. Near the horizon, the warm yellow lunar disk was a bit ruffled and dimmed by a long sight-line through dense, hazy atmosphere. Still it fit well with traffic and lights along East 96th street in this urban astroimage. The telephoto shot was (safely) taken from elevated ground looking east-southeast from Central Park, planet Earth. Of course, the East 96th street moon was the closest Full Moon to this year’s northern summer solstice.

Source: Astronomy Picture of the Day & Stan Honda

The Planets

The Planets – Ra Uru Hu – Introduction

The planets play a key role in the design of who we are. In fact, everything is based on the movements and impact of the planetary spheres.

The key to understanding the impact of something as distant as a planet on our lives is a tiny, subatomic particle known as the neutrino. Neutrinos are extremely fine matter produced by the nuclear reactions within stars. All the stars, including our own Sun, are producing neutrinos all the time. The stars out in space are constantly beaming these neutrinos at us, and being made of such fine substance, the neutrinos can pass through our bodies, as well as the body of the Earth. Imagine then, how the movements of the planets around our Sun refract the neutrino information as it passes into us.

Planets vary greatly in density and makeup. Some consist of solid rock, whilst others consist purely of layers of gases. Every planet also has its own mythology as perceived by man. Our mythologies are, and always have been, our method of attuning to our greater body.

The planets are our local programming agents. This is why we have always seen them as the gods in our mythologies down the ages. Every planet lends its flavor to our nature.

Sun – Our Light – Yang

Here on Earth, scientists have estimated that 70% of the neutrinos that pass through the Earth come from our Sun. The remainder comes from either Jupiter or the stars in deep space. Thus, 70% of all the neutrino information that we receive is seen in the position of our Sun and Earth. The Sun represents the primary yang force of our nature. It is the archetype of the Father, just as the Earth is the Mother. The Sun and Earth are the prime yin/yang within us all. The Sun creates the electromagnetic field of the solar cell in which we live. The design Sun represents the bio-genetic themes inherited from our father. If you look at your own design Sun, you will see the theme that you have inherited from your father. The personality Sun is the window through which the very light of who we are shines out on the world.
Read more

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