Category: astronomy and cosmology

Readers’ wildlife photos

August 27, 2022 • 8:00 am

Today we have a mixture of animals and astronomy. The readers’ captions and IDs are indented, and you can enlarge the photos by clicking on them.

The first three photos are from reader Terry Platt.

The weather hasn’t been helpful recently, but here are some H-alpha images of other objects in the Cygnus region. The NGC7000 image shows an impressive ‘wall’ of hot hydrogen with dark dust clouds. This region is part of the ‘North America’ nebula, which is a very large area of hydrogen emission to the northeast of the bright star Deneb. The nebula overall is vaguely similar to the shape of the USA and this part is ‘California and New Mexico’. It is about 2590 light years from Earth.

The other two images are of the planetary nebula M27. One is processed to show a ‘visual’ appearance, as the eye might see, while the other is very strongly contrast boosted to show the extensive, but faint, outer extensions. Planetary nebulae are the remnants of Sun-like stars, which have exhausted their hydrogen and blown most of their outer layers into the surrounding space. This process begins with ‘helium flashes’ where the helium rich star detonates helium burning for short periods and blows away its outer layers – this is the source of the faint extensions. As the star ages further, the process becomes more continuous and the core of the star is finally exposed as a very hot, but tiny, ‘white dwarf’ . M27 is at this stage and the white dwarf core can be faintly seen at its centre – the Sun may look something like this in about 10 billion years from now. M27 is about 1350 light years away in the constellation of Vulpecula.

Visual image:

Contrast boosted:

And two arthropods by Tony Eales:

More proof, if needed, that jumping spiders are the cats of the arachnid order. A study was published showing sleeping jumping spiders twitch in their sleep and even show what looks like REM periods associated with these twitches. Spider dreams? [JAC: Photos are Tony’s]

And then only a week later I see a story on consciousness in bees.  Here are some small stingless bees looking at me and presumably wondering if I am sentient:

Hubble Photo of the week

July 18, 2022 • 8:30 am

Let’s not forget the Hubble Space Telescope, now overshadowed by the Webb. Yet the Hubble site, run by NASA and the ESA (European Space Agency) still issues a weekly photo. Here’s this week’s, called “Lens Flair“.  Look at that mirror image galaxy!

Part of the description:

This intriguing observation from the NASA/ESA Hubble Space Telescope shows a gravitationally lensed galaxy with the long-winded identification SGAS J143845+145407. Gravitational lensing has resulted in a mirror image of the galaxy at the centre of this image, creating a captivating centrepiece.

Gravitational lensing occurs when a massive celestial body — such as a galaxy cluster — causes a sufficient curvature of spacetime for the path of light around it to be visibly bent, as if by a lens. Appropriately, the body causing the light to curve is called a gravitational lens, and the distorted background object is referred to as being “lensed”. Gravitational lensing can result in multiple images of the original galaxy, as seen in this image, or in the background object appearing as a distorted arc or even a ring. Another important consequence of this lensing distortion is magnification, allowing astronomers to observe objects that would otherwise be too far away or too faint to be seen. . .

. . . This particular lensed galaxy is from a set of Hubble observations that take advantage of gravitational lensing to peer inside galaxies in the early Universe. The lensing reveals details of distant galaxies that would otherwise be unobtainable, and this allows astronomers to determine star formation in early galaxies. This in turn gives scientists a better insight into how the overall evolution of galaxies has unfolded.

Gravitational lensing, caused by the curvature of spacetime by gravity, causes light to bend. This was predicted by Einstein’s theory of relativity, and that theory is visually confirmed by images like this. (It also constituted the first test of general relativity by Eddington and his collaborators in 1919.

Credit: ESA/Hubble & NASA, J. Rigby

 

Webb Space Telescope reveals first image, more to come this morning at 10:30 a.m. EST

July 12, 2022 • 8:00 am

You all know that yesterday and today began the public roll-out of photos from the Webb Space Telescope. And the first one, released yesterday and shown below, is a doozy.  Farther down I’ll tell you how to watch when today’s allotment is reveal. First, the photo and what NASA had to say about it (my emphasis). Remember, though, that the photos will be revealed 1½ hours after this post goes up.

NASA’s James Webb Space Telescope has produced the deepest and sharpest infrared image of the distant universe to date. Known as Webb’s First Deep Field, this image of galaxy cluster SMACS 0723 is overflowing with detail.

Thousands of galaxies – including the faintest objects ever observed in the infrared – have appeared in Webb’s view for the first time. This slice of the vast universe covers a patch of sky approximately the size of a grain of sand held at arm’s length by someone on the ground.

This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks.

The image shows the galaxy cluster SMACS 0723 as it appeared 4.6 billion years ago. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying much more distant galaxies behind it. Webb’s NIRCam has brought those distant galaxies into sharp focus – they have tiny, faint structures that have never been seen before, including star clusters and diffuse features. Researchers will soon begin to learn more about the galaxies’ masses, ages, histories, and compositions, as Webb seeks the earliest galaxies in the universe.

This image is among the telescope’s first-full color images. The full suite will be released Tuesday, July 12, beginning at 10:30 a.m. EDT, during a live NASA TV broadcast.

Here’s that stunning photo. Be sure to go to the NASA YouTube site below at 10:30 this morning:

Matthew sent two tweets showing the vastly improved vision of the sky that Webb’s afforded us. Be sure to click on the arrows to see the two two-photo gifs:

A one-minute video showing the improvement compared to previous optical instruments.

Doesn’t that make you feel small? The “pale blue dot” pales before such an image. But we should also be very proud of our species for creating an instrument that can show us the Universe and our place in it.

When and where to watch:

The Verge gives us the schedule for releasing the photos this morning:

Tuesday, July 12 (Image Release Day)

9:45 a.m. – Live, opening remarks by agency and Webb leadership will air on NASA TV, the NASA app, and the agency’s website ahead of the first images release.

10:30 a.m. – Live coverage of the image release broadcast will air on NASA TV, the NASA app, and the agency’s website. The public also can watch live on Facebook, Twitter, YouTube, Twitch, and Daily Motion.

. . .NASA has planned a series of briefings on July 12th to roll out the rest of the images. First, at 9:45AM ET, there will be opening remarks by leadership at NASA and the JWST team. Then, at 10:30AM ET, NASA should reveal the remaining images during a live broadcast, which will be followed by a media press conference at NASA’s Goddard Space Flight Center at 12:30PM ET. It’s going to be a jam-packed day of content, but if you’re looking to just see the remaining images, 10:30AM ET is the time to tune in.

Scheduled time: New York: 10:30AM / San Francisco: 7:30AM / London: 3:30PM / Berlin: 4:30PM / Moscow: 5:30PM / New Delhi: 8:00PM / Beijing: 10:30PM / Tokyo: 11:30PM / Melbourne: 12:30AM

And you can conveniently watch the release at NASA’s YouTube site below. The site will host festivities after the photo release and there will be more stuff on Wednesday, though no new photos. Consult the NASA site for details.

The Royal Observatory’s Astronomy Photographer of the Year Contest

July 6, 2022 • 8:00 am

Instead of readers’ wildlife today (I’m saving up), let’s see some entries from the Royal Observatory at Greenwich’s Astronomy Photographer of the Year Contest. The shortlisted entires have been reproduced in several places. The ones below are below from the Times, but Forbes also has an array, with this note:

The world’s most prestigious competition for cosmic images has revealed its shortlist—and it’s packed with wonder.

From the Moon and eclipses to comets and the northern lights, the shortlisted images for this year’s Astronomy Photographer of the Year have been plucked from over 3,000 entries from amateur and professional photographers in 67 countries.

Organized by London’s Royal Observatory Greenwich and sponsored by Liberty Specialty Markets and in association with BBC Sky at Night Magazine, this 14th annual competition will announce its winners on September 15, 2022.

The Times reports that the photos are on exhibit at Britain’s National Maritime Museum, which also happens to be in Greenwich.

Click on the screenshot to see them all (beware as the Times of London, where this was published, often uses a paywall); I’ll show my favorite six (with credits, of course), but there are 15, all gems. The paper’s captions are indented; click on the photos to enlarge them.

A partial eclipse of the Sun shot from Romano d’Ezzelino in the Veneto region of Italy on June 10 last year. It was a day of low solar activity, enabling the photographer to capture this unusually crisp image of the Moon’s silhouette. ALESSANDRO RAVAGNIN

The Northern Lights are reflected in the still waters of a lake in Alberta, Canada. SHANE TURGEON

There are lots of pictures of the Sun.

Clouds of hydrogen gas give way as the magnetic field lines of the Sun snap and clash together. This display of nature, taken from Los Angeles, creates astonishing features, known as prominences. SIMON TANG

Chidiya Tapu, in India, is rich in flora and fauna. Far from city lights, the nature reserve in the Andaman Islands archipelago is ideal base for wide-field astrophotography. Here, the Milky Way seems to mirror the water on its course. VIKAS CHANDER

The Soul nebula and its core, as seen from China. To its east is a complex of nebulae and star clusters known as the Heart nebula. Together they are often referred to as Heart and Soul. NAN WANG, BINYU WANG

This must have been taken near Death Valley (or the Panamint Valley), places where I’ve spent months collecting flies.  So I suppose this is my favorite.

Viewed from California under a quadruple arch, the stars circle around Polaris, in this stack of 33 four-minute exposures. The Sierra Nevada mountain range fills the horizon and Mount Whitney, the tallest peak in the continental United States, is on the far left. SEAN GOEBEL

h/t: Malcolm, Ginger K.

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 Space.com:

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.

More:

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.

 

Readers’ wildlife photos and videos

November 24, 2020 • 8:00 am

We have two contributors today. First, reader “sherfolder” sent us some photos and videos of penguins, and I can’t resist posting penguins. Sherfolder’s captions are indented:

I send you some pictures I took in March of African Penguins at Seaforth Beach, near Simons Town on the Cape Peninsula.

African penguins, also known as the Cape penguin or South African penguin, live on the west coast of Africa, on the islands of Angola and Namibia to the South African east coast. They are pursuit divers and forage in the open sea, where they pursue fish such as sardines and anchovies.

In 1910, the population of African penguins was estimated at 1.5 million. In 2010, the total African penguin population was at 55, 000. At this rate of decline, the African penguin is expected to be extinct in the wild by 2026. The total breeding population across both South Africa and Namibia fell to a historic low of about 20.850 pairs in 2019.

By the way, the German name for that species (Spheniscus demersus) is “Brillen-Pinguine” (that would mean in English: “Eyeglass penguins”), which is probably due to their facial drawings, although I don’t think that those markings actually resemble glasses.

The first video shows three penguins that have just landed on the beach from the sea and are now setting out to climb a rock, you could have touched them, they came so close.

The second video shows a group of four penguins diving and swimming almost in formation gracefully and swiftly in the sea.

Our second contributor is Tim Anderson from Australia, with one of his lovely astronomy photos:

This is the Tarantula Nebula (NGC2070), an enormous star-forming region inside the Large Magellanic Cloud, the nearest galaxy to the Milky Way. It contains some of the largest stars ever measured from Earth.

 

A fantastic view of the surface of Mars

August 25, 2020 • 2:00 pm

Here’s a stunning ten-minute video of the surface of Mars composed of a series of images strung together (up to a thousand in one panorama), with the photos coming from three different rovers. The large panoramas are then scanned with a video camera, a technique made famous by Ken Burns in his documentaries.

I don’t know about you, but watching this, and seeing Mars in broad daylight, made me feel plenty weird. No human has set foot here, and perhaps, though the planet once had water, there was never life of any sort.  And yet we fly spacecraft there and plant fiendishly clever rovers that roam the surface and show us what it’s like.

Will humans ever make it there (a seven-month trip one way)? I’ll never know.

Off to get a haircut!

 

h/t: Paul