Pic of the Week: Telescope Teamwork with MACS0416

Image (Credit): Galaxy cluster MACS0416. (NASA, ESA, CSA, STScI, J. Diego (Instituto de Física de Cantabria, Spain), J. D’Silva (U. Western Australia), A. Koekemoer (STScI), J. Summers & R. Windhorst (ASU), and H. Yan (U. Missouri))

This week’s image combines the talents of the Hubble Space Telescope and the James Webb Space Telescope to create a dazzling show of light. The galaxy cluster, known as MACS0416, is about 4.3 billion light-years from Earth.

Here is much more from the European Space Agency:

The image reveals a wealth of details that are only possible by combining the power of both space telescopes. It includes a bounty of galaxies outside the cluster and a sprinkling of sources that vary over time, likely due to gravitational lensing — the distortion and amplification of light from distant background sources.

This cluster was the first of a set of unprecedented, super-deep views of the Universe from an ambitious, collaborative Hubble programme called the Frontier Fields, inaugurated in 2014. Hubble pioneered the search for some of the intrinsically faintest and youngest galaxies ever detected. Webb’s infrared view significantly bolsters this deep look by going even farther into the early Universe with its infrared vision.

To make the image, in general the shortest wavelengths of light were colour-coded blue, the longest wavelengths red, and intermediate wavelengths green. The broad range of wavelengths, from 0.4 to 5 microns, yields a particularly vivid landscape of galaxies.

Those colours give clues to galaxy distances: the bluest galaxies are relatively nearby and often show intense star formation, as best detected by Hubble, while the redder galaxies tend to be more distant and are best detected by Webb. Some galaxies also appear very red because they contain copious amounts of cosmic dust that tends to absorb bluer colours of starlight.

While the new Webb observations contribute to this aesthetic view, they were taken for a specific scientific purpose. The research team combined their three epochs of observations, each taken weeks apart, with a fourth epoch from the CANUCS (CAnadian NIRISS Unbiased Cluster Survey) research team. The goal was to search for objects varying in observed brightness over time, known as transients.

They identified 14 such transients across the field of view. Twelve of them were located in three galaxies that are highly magnified by gravitational lensing, and they are likely to be individual stars or multiple-star systems that are briefly very highly magnified. The remaining two transients are within more moderately magnified background galaxies and are likely to be supernovae.

The finding of so many transients with observations spanning a relatively short timeframe suggests that astronomers could find many more transients in this cluster and others like it through regular monitoring with Webb.

Among the transients the team identified, one stood out in particular. Located in a galaxy that existed about 3 billion years after the Big Bang, it is magnified by a factor of at least 4000. The team nicknamed the star system Mothra in a nod to its ‘monster nature’, being both extremely bright and extremely magnified. It joins another lensed star that the researchers previously identified and that they nicknamed Godzilla. Both Godzilla and Mothra are giant monsters known as kaiju in Japanese cinema.

Interestingly, Mothra is also visible in the Hubble observations that were taken nine years earlier. This is unusual, because a very specific alignment between the foreground galaxy cluster and the background star is needed to magnify a star so greatly. The mutual motions of the star and the cluster should have eventually eliminated that alignment.

The most likely explanation is that there is an additional object within the foreground cluster that is adding more magnification. The team was able to constrain its mass to be between 10 000 and 1 million times the mass of our Sun. The exact nature of this ‘milli-lens’, however, remains unknown. It is possible that the object is a globular star cluster that’s too faint for Webb to observe directly.

Pic of the Week: The Horsehead Nebula

Image (Credit): The Horsehead Nebula courtesy of the Euclid mission. (ESA / Euclid / Euclid Consortium / NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi; CC BY-SA 3.0 IGO)

This week’s image is from the European Space Agency’s (ESA) Euclid telescope. It is the famous Horsehead Nebula in all its beauty.

Here is a little more about the image from ESA:

Euclid shows us a spectacularly panoramic and detailed view of the Horsehead Nebula, also known as Barnard 33 and part of the constellation Orion. In Euclid’s new observation of this stellar nursery, scientists hope to find many dim and previously unseen Jupiter-mass planets in their celestial infancy, as well as young brown dwarfs and baby stars.

Pic of the Week: Ghostly Apparitions

Image (Credit): Constellation of Cepheus. (Bogdan Jarzyna)

I wanted to share one more image before we leave Halloween behind, this time from NASA’s Astronomy Picture of the Day.

Here is a description from NASA regarding the image above:

The jeweled expanse, filled with faint, starlight-reflecting clouds, drifts through the night in the royal constellation of Cepheus. Far from your own neighborhood on planet Earth, these ghostly apparitions lurk along the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over two light-years across and brighter than the other spooky chimeras, VdB 141 or Sh2-136 is also known as the Ghost Nebula, seen toward the bottom of the featured image. Within the reflection nebula are the telltale signs of dense cores collapsing in the early stages of star formation.

Pic of the Week: Get Ready for Halloween!

Image (Credit): View of Jupiter taken by the NASA’s Juno mission. (NASA/JPL-Caltech/SwRI/MSSS, Vladimir Tarasov)

NASA has an image for all of us just in time for Halloween. The strange face you see above is a view of Jupiter taken on September 7, 2023 by NASA’s Juno spacecraft on its 54th close flyby of the planet.

NASA explains what you are seeing in this northern region of Jupiter:

The image shows turbulent clouds and storms along Jupiter’s terminator, the dividing line between the day and night sides of the planet. The low angle of sunlight highlights the complex topography of features in this region, which scientists have studied to better understand the processes playing out in Jupiter’s atmosphere.

Now I want to see the images from the first 53 flybys to understand what we might have missed.

Pic of the Week: Annular Solar Eclipse Over the U.S.

Image (Credit): Lunar shadow captured on October 14, 2023. (NASA)

This image of last week’s annular solar eclipse was captured by NASA’s Earth Polychromatic Imaging Camera (EPIC) imager carried aboard the Deep Space Climate Observatory (DSCVR), which is a joint venture between NASA, NOAA, and the U.S. Air Force.

NASA made this statement regarding the image:

An annular eclipse occurs when the Moon passes in front of the Sun but is too far from Earth to completely obscure it. The Moon is at or near its farthest distance from Earth—known as its apogee—during an annular eclipse, making it look smaller in the sky. This leaves the Sun’s edges exposed in a red-orange ring, dubbed the “ring of fire.” A satellite caught an earthly view of the event, as the Moon’s shadow crossed North America.

NASA also provided a map showing those areas in the United States most impacted by the eclipse (shown below).

Image (Credit): Map showing the dark path of the annularity stretching across the lower 48 states from Oregon to Texas. (NASA)