Readers’ wildlife photos

June 25, 2022 • 8:00 am

A few kind readers sent in wildlife photos, but I’m going to conserve them for a day or so to accumulate a reasonable stash.  Today, then, we have three photos: a sign and two astronomy pics that show part of the “planet parade” of a few days ago.

The astronomy came from reader Bryan Lepore yesterday, whose notes are indented (click photos to enlarge them):

I send the best picture I could get of the planet parade this morning. I used an iPhone 13 and iOS with nothing added. I used Night Sky as an aid for identification of the planets.Venus is among the tree tops on the left. The planet just above the treetops on the right is probably Jupiter, though Saturn was near it.

… I also got some bats (not shown). Clearly s learning experience – the luminosity would change as the clouds filtered the light, so Jupiter could become as dim as Saturn usually is, and there was no reference as the clouds hid planets alternately. A learning experience.Come to think of it, I’d like to include a neat photo of Mars and Jupiter together from last week – I didn’t know they’d line up today :

From Dan Fromm. I think someone should collect a website of various “animal crossing” signs. (Actually, I bet there is one.)

Here’s a photo from a recent field trip to the Dominican Republic.  Photo by Mark H. Sabaj Perez, Sr. Collection Manager, Ichthyology, the Academy of Natural Sciences of Drexel University.
I think it is a Solenodon crossing sign.  Location, on the road from Duverge to Puerto Escondido.

What is a Solenodon? From Wikipedia:

Solenodons (/sˈlɛnədɒnz/, meaning “slotted-tooth”) are venomous, nocturnal, burrowing, insectivorous mammals belonging to the family Solenodontidae /sˌlɛnəˈdɒntɪd/. The two living solenodon species are the Cuban solenodon (Atopogale cubana), and the Hispaniolan solenodon (Solenodon paradoxus). Threats to both species include habitat destruction and predation by non-native cats, dogs, and mongooses, introduced by humans to the solenodons’ home islands to control snakes and rodents.

Here’s a photo (not mine or Dan’s, but from the Internet) of the Hispaniolan solenodon. Because it’s threatened, there should be a sign. The guy is wearing gloves because the creature has a bite with venomous salive.  More:

Today, the solenodon is one of the last two surviving native insectivorous mammals found in the Caribbean, and one of the only two remaining endemic terrestrial mammal species of Hispaniola.


Planet parade tonight: you can see five with the naked eye (plus the Moon) if conditions are right

June 23, 2022 • 10:45 am

Throughout the month of June, the planets have been falling into a rough line as viewed from Earth.  Tonight, five of them will be visible with the naked eye before sunrise times—aligned according to their distance from the Sun. This won’t happen again until 2040.  And if you have a good view and no city lights around, tonight will be an excellent time to see Mercury, Venus, Mars, Jupiter, and Saturn (Neptune and Uranus will be too faint to see unless you have a telescope).

In principle, you could see the array below tomorrow morning, but only five of planets with the naked eye. But you get a crescent Moon thrown in, and right in the proper place: between Venus and Mars.

You should start your observations before dawn, bringing binoculars if you have them:

From Star Walk:

Also from Star Walk:

 Don’t miss the large planet parade on June 24, 2022! 🪐

✨ The most spectacular planet parade of the year will take place on the morning of June 24. Observers will see five planets of the Solar System aligned in the sky: Mercury, Venus, Mars, Jupiter, and Saturn.

❗ In fact, this will be a seven-planet alignment as Neptune and Uranus will also join the celestial show. However, these two giant planets are too dim to be spotted with the naked eye.

👀 You should start your observations about an hour before dawn. The planets will extend from east to south (from north to east in the southern latitudes) across the sky. Observers from the Southern Hemisphere will have a better view — the planets there will rise earlier and climb much higher.

🌙 An additional bonus is the waning crescent Moon, shining between Venus and Mars. It will be slightly out of the “planetary line,” traveling from planet to planet during the latter half of June.

📱 To easily locate and identify planets on the sky’s dome, you can use mobile apps like Star Walk 2 or Sky Tonight. Simply point your device at the sky, and the apps will show you what object you’re looking at. 👇

#planets #planetparade #planetparade2022 #planetaryalignment #planetalignment #astronomy

Sky & Telescope has some fancy diagrams and more information. All of June is good to see this, but two periods, June 3-4 and tonight, are notable. (I’ll neglect the days that are gone):

June 24: According to Sky & Telescope magazine, the planetary lineup this morning is even more compelling. To begin with, Mercury will be much easier to snag, making the five-planet parade that much more accessible. And you’ll have about an hour to enjoy the sight, from when Mercury pops above the horizon to when the rising Sun washes it out of the sky. But the real bonus is the waning crescent Moon positioned between Venus and Mars, serving as a proxy Earth. By this time of month, the planets are spread farther across the sky — the distance between Mercury and Saturn will be 107°.

Here’s a diagram of what you can see 45 minutes before sunrise tomorrow. It’s from the Sky & Telescope post, and the caption is indented:

At dawn on June 24th, the crescent Moon joins the planetary lineup. It’s conveniently placed between Venus and Mars, serving as a proxy Earth.

I wish I could see this splendid array, but there are too many lights around where I live. I hope I’ll get a photo to post tomorrow.

Click to enlarge:


See all the satellites!

May 17, 2022 • 1:30 pm

I didn’t realize how much trash is orbiting the earth until I saw this interactive satellite site.

From Barry via BoingBoing, which says only this about the site:

 “This low earth orbit visualization tool allows users to see satellites all over the world. You can click on a satellite to see details about it, or you can perform a search using specific filters. During my time playing with the site, I saw 19,165 satellites. Zoom in and out to see the orbit from any perspective.”

First, the credits they give:

Then click on the screenshot, which shows what’s up there above us, to play with the site

Here’s what I found you can do in just a short look:

  • Click on any satellite and see what it is and who put it up
  • Move the Earth around to see what’s where
  • Distinguish between debris (there’s a lot of it!), rocket bodies, satellites, beams (whatever they are;they seem to come from the U.S. and New Zealand), and other stuff
  • Search for satellites by name
  • Filter satellites by perigee, country of orgin, object type, and so on.

You may tire of this quickly, as I did, but it’s still astounding that there’s so much crap orbiting the Earth. It’s a wonder these things don’t run into each other! (Yes, I know that space is big and the elevations differ.)


Another black hole visualized, this one at the heart of our own galaxy

May 12, 2022 • 10:45 am

I had no idea that there was a big black hole at the center of the Milky Way, but that is indeed the case, though it seems to have been discovered not that long ago and photographed just now, as documented in the Event Horizon site below (click on screenshot).

The hole, called Sagittarius A* (or SgrA*) was discovered when several stars were orbiting around an invisible spot in the galaxy. Although black holes are themselves invisible, they can be visualized because they’re surrounded by a ring of glowing gas. The website Event Horizon Telescope (which is the group that visualized it and the first black hole) describes the finding and shows the photos, which are, after all, what we want to see. Producing them was itself a remarkable feat, as described below.  Click on the screenshot below to read:

From the site:

Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a “shadow”) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity,” said EHT Project Scientist Geoffrey Bower from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. “These unprecedented observations have greatly improved our understanding of what happens at the very centre of our galaxy, and offer new insights on how these giant black holes interact with their surroundings.” The EHT team’s results are being published today in a special issue of The Astrophysical Journal Letters..

Because the black hole is about 27,000 light-years away from Earth, it appears to us to have about the same size in the sky as a donut on the Moon. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope [1]. The EHT observed Sgr A* on multiple nights, collecting data for many hours in a row, similar to using a long exposure time on a camera.

Here you go. The site also shows, visually, how different images were averaged and combined to create this “definitive” photo (click photos to enlarge them):

Caption from website: This is the first image of Sgr A*, the supermassive black hole at the centre of our galaxy. It’s the first direct visual evidence of the presence of this black hole. It was captured by the Event Horizon Telescope (EHT), an array which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope. The telescope is named after the event horizon, the boundary of the black hole beyond which no light can escape.   Although we cannot see the event horizon itself, because it cannot emit light, glowing gas orbiting around the black hole reveals a telltale signature: a dark central region (called a shadow) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun. The image of the Sgr A* black hole is an average of the different images the EHT Collaboration has extracted from its 2017 observations.  In addition to other facilities, the EHT network of radio observatories that made this image possible includes the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder EXperiment (APEX) in the Atacama Desert in Chile, co-owned and co-operated by ESO is a partner on behalf of its member states in Europe.

You may remember that 3 years ago first image of a black hole, M87*, was released. That one, called M87*, sits at the centre of the more distant Messier 87 galaxy, and is a much larger hole—a thousand times the size of SgrA*. Here’s a picture of that “first” black hole from the NYT, with the newly added visualization of polarized light.

More from the site:

The two black holes look remarkably similar, even though our galaxy’s black hole is more than a thousand times smaller and less massive than M87* [2]. “We have two completely different types of galaxies and two very different black hole masses, but close to the edge of these black holes they look amazingly similar,” says Sera Markoff, Co-Chair of the EHT Science Council and a professor of theoretical astrophysics at the University of Amsterdam, the Netherlands. “This tells us that General Relativity governs these objects up close, and any differences we see further away must be due to differences in the material that surrounds the black holes.”

. . . . The effort was made possible through the ingenuity of more than 300 researchers from 80 institutes around the world that together make up the EHT Collaboration. In addition to developing complex tools to overcome the challenges of imaging Sgr A*, the team worked rigorously for five years, using supercomputers to combine and analyse their data, all while compiling an unprecedented library of simulated black holes to compare with the observations.

Scientists are particularly excited to finally have images of two black holes of very different sizes, which offers the opportunity to understand how they compare and contrast. They have also begun to use the new data to test theories and models of how gas behaves around supermassive black holes. This process is not yet fully understood but is thought to play a key role in shaping the formation and evolution of galaxies.

So there you go. I consider the prediction and then verification that these bizarre entities exist to be of the triumphs of the human mind. The theory began as an outgrowth of Einstein’s General Theory of Relativity, and required the work of many people. Ultimately, Stephen Hawking and Roger Penrose gave the definitive proof that black holes were a natural result of Einstein’s theory. Then they were “photographed” using radioastronomy. For his theoretical work, Penrose won half of the 2020 Physics Prize, but Hawking was dead by then or almost surely would have shared the Prize.

Here’s a happy man:

h/t: Matthew

The first picture from the James Webb Space Telescope!—and explanatory lagniappe

February 13, 2022 • 10:00 am

This was put up by NASA a couple of days ago, so why didn’t we hear about it? But It shows that WE DID IT, and by “we”, I mean “humanity”. Getting that big and complicated puppy into space was a fantastic achievement and now it seems to be working. First, the image:

It’s the same star pictured 18 times—once in each mirror. Yeah, so doesn’t seem so exciting, does it? But it really is, because it shows the telescope works and the mirrors can now be tweaked to take the pictures the Webb was designed to take.  (The different images of the same star will be brought together.) As NASA explains:

The James Webb Space Telescope is nearing completion of the first phase of the months-long process of aligning the observatory’s primary mirror using the Near Infrared Camera (NIRCam) instrument.

The team’s challenge was twofold: confirm that NIRCam was ready to collect light from celestial objects, and then identify starlight from the same star in each of the 18 primary mirror segments. The result is an image mosaic of 18 randomly organized dots of starlight, the product of Webb’s unaligned mirror segments all reflecting light from the same star back at Webb’s secondary mirror and into NIRCam’s detectors.

What looks like a simple image of blurry starlight now becomes the foundation to align and focus the telescope in order for Webb to deliver unprecedented views of the universe this summer. Over the next month or so, the team will gradually adjust the mirror segments until the 18 images become a single star.

“The entire Webb team is ecstatic at how well the first steps of taking images and aligning the telescope are proceeding. We were so happy to see that light makes its way into NIRCam,” said Marcia Rieke, principal investigator for the NIRCam instrument and regents professor of astronomy, University of Arizona.

Click the screenshots below here for more:

Here’s a 3-minute video showing first image arriving at NASA. We haz photons! But watch the second video as well.

If you want a hyper-enthusiastic summary of what this photo is and means, here’s Dr Becky Smethurst from Oxford. Her bio at the YouTube site:

I’m Dr. Becky Smethurst, an astrophysicist at the University of Oxford. I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don’t know. If you’ve ever wondered about something in space and couldn’t find an answer online – you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.

If you want to understand what Smethurst means by “naff,” reader Don, who sent me this link, also points to a page explaining that British term.


Deployment of Webb Space Telescope’s mirror’s successful, but we’re not there yet

January 20, 2022 • 11:00 am

The toughest bit, though seems past: successfully unfolding the entire mirror of the Webb Space Telescope was the most delicate of all its operations, since nothing could fail without endangering the scope’s usefulness. And nothing did! NASA has reported, along with many other sites, that the main mirror deployment is, as they say, “nominal.”  From

JWST’s golden primary mirror includes 18 individual hexagonal segments, each controlled by seven actuators that allow precise movements. All 18 segments are now in their deployed positions several days sooner than scheduled.

Work began on the mirror segments on Jan. 12 and was expected to take about 10 days. But despite today’s announcement, those mirror segments aren’t quite ready to observe yet. First, NASA must conduct the painstaking process of fine-tuning every mirror’s position to turn 18 individual views of the universe into one large ultra-powerful mirror.

The team behind Webb expects that the entire mirror process will take about three months, all told.

Here’s a NASA video of the immensely complicated process of aligning all the mirrors once they’ve unfolded. I have faith in the Telescope Humans that all will be well.


If this works okay, and nothing else goes wrong, in a few months the scope will be in position and ready to send data. There is one more important maneuver:

Webb has one more key deployment milestone to complete, a trajectory burn that will insert the observatory into orbit around a spot in space dubbed the Earth-sun Lagrange point 2, or L2. L2 is located nearly 1 million miles (1.5 million kilometers) away from Earth, on the side of the planet opposite the sun.

According to a NASA timeline, JWST is expected to complete this final arrival maneuver on Sunday (Jan. 23).

A good site to follow is “Where is Webb?” NASA’s real-time timeline of the mission showing the location of the scope and what it’s doing. Below is a screenshot that you can click on to see where Webb is now. It’s approaching “L2 insertion” on the right! Click on the photo to enlarge it.


Wake up! Space telescope to be launched today at 7:20 Eastern time.

December 25, 2021 • 5:00 am

MERRY CHRISTMAS!  Here’s a present to the world from science—international science.

I know people are up in Europe, and if you’re an early riser in America, you’ll want to see this too (the Kiwis and Aussies will be asleep unless they’re night owls). The James Webb Space Telescope will be launched today, on Christmas Day, at 7:20 Eastern U.S. time, or 6:20 Chicago time. I’m already up at 4:30 to do my ablutions and have coffee before the big takeoff. The good news is that many Americans will be forced to be awake by early-rising kids who want to open their presents.

When this is posted it will be 6 a.m. Eastern U.S. time: 1 hour and 20 minutes to go! And the NASA feed below will have begun.

You know what’s happening: the space telescope, far more powerful than the Hubble, will provide oodles of scientific information, including detecting infrared light from billions of years ago. You can read about it at Wikipedia, or at the NASA site

Here’s the NASA live feed:

Fingers crossed!

A feed from the NASA site that does have commentary (click on screenshot to go to NASA t.v.):

And another live feed:

I believe all conditions are go (things are “nominal”, as they say), and only weather or one other thing could mess up the launch (xkcd cartoon courtesy of Matthew):

James Webb Space Telescope

December 20, 2021 • 11:30 am

On Wednesday, as the 13-minute “60 Minutes” segment below explains, the $10-billion-dollar James Webb Space Telescope will be launched.  Thirty days later, it will be nearly a million miles from Earth, in orbit around the Sun.

One of its goals is to detect leftover radiation traveling over billions of light years, giving us a glimpse of the past and, perhaps, into what “dark matter” is.  But, as you’ll see, it can also answer many other questions.

If you want to read more than you’ve absorbed from this segment, go to either the Wikipedia page or on the telescope’s NASA site.

I’m continuslly stunned by what humans can do with simple materials extracted from the Earth. And it’s great that this effort involves international cooperation.

h/t: Nicole

A near total lunar eclipse tonight

November 18, 2021 • 11:00 am

If you’re a night owl, you’ll want to watch the Moon tonight, especially around 1:00 a.m Eastern U.S. time, for there will be a rare near-total lunar eclipse of a full moon. Set your alarms now (I’ll be sleeping). (here and here) reports the event and tells you how to watch it online if there are too many clouds in your area. It’s not only a big eclipse, with the Earth’s shadow covering 97% of the visible Moon, but also a LONG one: almost exactly 6 hours long. It’s also the longest partial lunar eclipse in 6 centuries!:

It will be the second lunar eclipse of 2021 and, in some ways, will be similar to the last one on May 26. Most North Americans will again need to get up early and look low in the west toward daybreak. And again, the farther west you are the better, as the moon will appear much higher from the western part of the continent as opposed to locations farther to the east. It will also be the longest partial lunar eclipse in 580 years, lasting just over 6 hours, with its pass through the darkest part of Earth’s shadow taking about 3 hours, 28 minutes and 23 seconds, and also the longest this century.

Here’s where it will be visible, including all the U.S., Canada, Central America, western South America, and Eastern Asia:

And a U.S. chart of the various phases:

If it’s clear, I’ll get to see the tail end as I walk to work.

You may be wondering why they call this the “Beaver Moon” eclipse. The Washington Post says this:

At the time of the eclipse, the moon will be full. Some refer to the November full moon as the “beaver moon,” a name assigned by Native Americans when beavers were particularly active in preparation for winter and it was time to set traps, according to NASA.

If you want to watch it online, here are four sites:

The Griffith Observatory in Los Angeleswill feature a timelapse video of the eclipse, weather permitting, on its YouTube page. The timelapse will start at 9 a.m. EST (1400 GMT/6 a.m. PST), with an online broadcast beginning before that on Friday, Nov. 19 at 1 a.m. EST (0600 GMT/ 10 p.m. PST on Nov. 18).

Time and Date will start its livestream on YouTube at 1 a.m. EDT (0600 GMT) on YouTube.

The Virtual Telescope Project will broadcast live from Rome starting at 2 a.m. EDT (0700 GMT).

The Astronomical Society of South Australiawill have broadcasts on YouTube or Facebook starting at 4:30 a.m. EST (0930 GMT or 7 p.m. local time).

And here’s an idea of how it will look (it won’t become invisible, just orange):

h/t Ginger K.

The Sun throws up

November 5, 2021 • 2:45 pm

Here’s a lovely NASA video a solar flare imaged several different ways, though I’m not fond of the music. Read the link in the preceding sentence to see how they’re caused.

On August 31, 2012 a long filament of solar material that had been hovering in the sun’s atmosphere, the corona, erupted out into space at 4:36 p.m. EDT. The coronal mass ejection, or CME, traveled away from the sun at over 900 miles per second. This movie shows the ejection from a variety of viewpoints as captured by NASA’s Solar Dynamics Observatory (SDO), NASA’s Solar Terrestrial Relations Observatory (STEREO), and the joint ESA/NASA Solar Heliospheric Observatory (SOHO).

And here’s a “cannibal coronal mass” from just three days ago: one ejection eats up another one. These things can cause spectacular auroras on Earth.

h/t: Rick