Tag: Euclid

ESA releases first section of grand mosaic of the sky to be produced by Euclid

9:29 am

Euclid's first released mosaic
For original images, go here, here, and here.

The European Space Agency (ESA) yesterday released the first mosaic section of a grand atlas of the sky that its recently launched Euclid space telescope was designed to produce.

The image to the right, assembled from several images but of very low resolution to post here, will give my readers an idea of Euclid’s capabilities. The top image shows this first mosaic in green, made up of 260 photos, laid on top of the sky atlases produced by the Gaia and Plank orbiting telescopes. As you can see, it covers only about 12% of the sky, but was also produced in only the last six months, since science observations began in February. When complete, the Euclid atlas will cover one third of the sky, and provide very high resolution data for that entire area.

The middle image provides a close-up of that mosaic, albeit in very low resolution.

This first piece of the map already contains around 100 million sources: stars in our Milky Way and galaxies beyond. Some 14 million of these galaxies could be used to study the hidden influence of dark matter and dark energy on the Universe. “This stunning image is the first piece of a map that in six years will reveal more than one third of the sky. This is just 1% of the map, and yet it is full of a variety of sources that will help scientists discover new ways to describe the Universe,” says Valeria Pettorino, Euclid Project Scientist at ESA.

The bottom image, once again at low resolution to post here, zooms into only one small section of that mosaic, and illustrates the high level of detail each Euclid image will contain. Though the details in this photo seem a bit fuzzy, at full resolution they remain remarkably sharp. To get an idea of how good that resolution is, see an earlier Euclid close-up photo released in May.

Euclid doesn’t take pictures with the quite the resolution of Hubble (its primary mirror at 1.2 meters diameter is half the width). While Hubble was designed to zoom in at specific objects and do so over and over if desired, Euclid will instead provide a high resolution snapshot of the entire sky, at a resolution almost as good, in both optical and infrared wavelengths.

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Euclid releases new images and first science results

10:37 am

Euclid image
Click for original image.

The Euclid science team today released five early science images in connection of the publication of ten papers.

The picture to the right is one of those images, cropped, reduced, and sharpened to post here. From the caption:

In this image Euclid showcases NGC 6744, an archetype of the kind of galaxy currently forming most of the stars in the local Universe. Euclid’s large field-of-view covers the entire galaxy, capturing not only spiral structure on larger scales but also exquisite detail on small spatial scales. This includes feather-like lanes of dust emerging as ‘spurs’ from the spiral arms, shown here with incredible clarity.

Scientists are using this dataset to understand how dust and gas are linked to star formation; map how different star populations are distributed throughout galaxies and where stars are currently forming; and unravel the physics behind the structure of spiral galaxies, something that is still not fully understood after decades of study.

Euclid is a wide-field space telescope that has instruments that observe in both visible and near-infrared wavelengths. Its primary mirror at 1.2 meters is half the width of Hubble’s. More details about these early images and links to the new science results can be found here.

Unlike Hubble, it appears Euclid will not be used as a general observatory, at least initially. Its primary goal is to do a survey of one third of the sky, focusing on extragalactic sources outside the Milky Way. Once this is complete however it is possible the space telescope will be made available for other observations.

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Webb takes an infrared look at the mane of the Horsehead Nebula

10:01 am

Context images
Click for original image.

The mane of the Horsehead Nebula, seen in infrared
Click for original image.

The cool infrared image to the right, cropped, reduced, and sharpened to post here, was taken by the Webb Space Telescope and released today. The three pictures above provide the context, with the rectangle inside the rightmost image indicated the area covered by the close-up to the right.

Webb’s new images show part of the sky in the constellation Orion (The Hunter), in the western side of a dense region known as the Orion B molecular cloud. Rising from turbulent waves of dust and gas is the Horsehead Nebula, otherwise known as Barnard 33, which resides roughly 1,300 light-years away.

The nebula formed from a collapsing interstellar cloud of material, and glows because it is illuminated by a nearby hot star. The gas clouds surrounding the Horsehead have already dissipated, but the jutting pillar is made of thick clumps of material and therefore is harder to erode. Astronomers estimate that the Horsehead has about five million years left before it too disintegrates. Webb’s new view focuses on the illuminated edge of the top of the nebula’s distinctive dust and gas structure.

In the close-up, note the many distant tiny galaxies, both above the mane as well as glowing throught it.

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ESA: Euclid vision cleared after being fogged by ground ice, after launch

9:13 am

The European Space Agency (ESA) today announced that engineers have successfully “de-iced” the optics of its new Euclid space telescope that developed after it was launched in July 2023.

It was always expected that water could gradually build up and contaminate Euclid’s vision, as it is very difficult to build and launch a spacecraft from Earth without some of the water in our planet’s atmosphere creeping into it. For this reason, there was an ‘outgassing campaign’ shortly after launch where the telescope was warmed up by onboard heaters and also partially exposed to the Sun, sublimating most of the water molecules present at launch on or very near Euclid’s surfaces. A considerable fraction, however, has survived, by being absorbed in the multi-layer insulation, and is now being slowly released in the vacuum of space.

After a huge amount of research – including lab studies into how minuscule layers of ice on mirror surfaces scatter and reflect light – and months of calibrations in space, the team determined that several layers of water molecules are likely frozen onto mirrors in Euclid’s optics. Likely just a few to few tens of nanometres thick – equivalent to the width of a strand of DNA – it’s a remarkable testament to the mission’s sensitivity that it is detecting such tiny amounts of ice.

While Euclid’s observations and science continue, teams have come up with a plan to understand where the ice is in the optical system and mitigate its impact now and in the future, if it continues to accumulate.

It appears this new process has worked, according to a short update at the link.

Normally spacecraft are vented both on the ground during thermal testing, as well as when they reach orbit. It appears some of these normal procedures were either insufficient for Euclid’s needs, or threatened its optics if done as usual. This press release suggests that Euclid required very targeted venting processes that would not harm its sensitive optics, and that the procedures have worked.

I must admit I am suspicious of these claims. During development and after launch Euclid has had a number of problems. First, back in 2017 the NASA instrument on the telescope had to be completely rebuilt when it was found to be defective. Second, after launch engineers discovered unexpected light leaks on the mirror that now limit where it can look. Third, the telescope required a software patch to fix its pointing system, which was confusing cosmic rays for guide stars, causing it to shift positions randomly.

I can’t help wondering if this icing on the mirrors was also due, not to actual planning as suggested by ESA’s press release, but to poor ground testing and engineering that missed what is a common problem on spacecraft and thus required a post-launch improvised fix. I admit I might be wrong, but I still wonder.

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Software patch saves Europe’s Euclid space telescope

10:03 am

Engineeers have successfully saved Europe’s new recently launched Euclid space telescope by installing a software patch that fixed the telescope’s inability to orient itself properly for long periods.

Shortly after launching on 1 July, the European space observatory Euclid started performing tiny, unexpected pirouettes. The problem revealed itself during initial tests of the telescope’s automated pointing system. If left unfixed, it could have severely affected Euclid’s science mission and led to gaps in its map of the Universe.

Now the European Space Agency (ESA) says that it has resolved the issue by updating some of the telescope’s software. The problem occurred when the on board pointing system mistook cosmic noise for faint stars in dark patches of sky, and directed the spacecraft to reorient itself in the middle of a shot.

The new software essentially reduces the amount of light that enters the pointing system, so that the noise is no longer detected. This means that observations however will have to be longer to obtain the same data, extending the mission.

Euclid’s goal is a follow-up on Europe’s Gaia mission, to map 1.5 billion galaxies in three dimensions. Gaia did it with the stars in the Milky Way. Euclid is looking deeper, requiring far greater precision and accuracy in pointing.

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Despite good first images from Euclid, the orbiting telescope has a problem

10:05 am

Even though the first light images from Euclid have been sharp and exactly what astronomers want, the orbiting telescope designed to make a 3D map of billions of galaxies has an issue that will likely put some limits to that map.

When the telescope started booting up, ESA observers were concerned by the appearance of light markings on the first images relayed to Earth. This, it confirmed, was due to sunlight filtering into the telescope, “probably through a tiny gap”.

A correction to Euclid’s position was able to offset this issue. It means that while the ESA is confident Euclid will be fine to proceed with its mapping mission, particular orientations for the telescope may not be possible.

A limitation like this means that the telescope will not being able to look in some directions and get mapping images. Thus, the overall map will have gaps, though it appears at this moment that the scientists think those gaps will not seriously impact the telescope’s overall work. We shall see.

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Euclid’s first images look good

9:19 am

Scientists have determined that the first test images from the two cameras on the recently launched orbiting Euclid space telescope are sharp and as expected.

Both VIS and NISP provided these unprocessed raw images. Compared to commercial products, the cameras are immensely more complex. VIS comprises 36 individual CCDs with a total of 609 megapixels and produces high-resolution images of billions of galaxies in visible light. This is how astronomers determine their shape. The first images already give an impression of the abundance that the data will provide.

NISP’s detector consists of 16 chips with a total of 64 megapixels. It operates in the near-infrared at wavelengths between 1 and 2 microns. In addition, NISP serves as a spectrograph, which splits the light of the captured objects similar to a rainbow and allows for a finer analysis. These data will allow the mapping of the three-dimensional distribution of galaxies.

Knowing that 3D distribution will allow scientists to better determine the nature of both dark energy (related to the acceleration of the universe’s expansion) and dark matter (related to an undiscovered mass that affects the formation and shape of galaxies).

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SpaceX launches Europe’s Euclid space telescope

9:26 am

SpaceX this morning successfully launched Europe’s Euclid space telescope, designed to map the spatial distribution of several billion galaxies across one third of the sky.

The first stage successfully completed its second flight, landing on a drone ship in the Atlantic. The two fairing halves completed their first flight.

This ESA science mission would have normally been launched on an Arianespace rocket, but Europe’s ability to launch anything now is nil, as it is about to retire its Ariane-5 rocket (with one launch left) and has so failed to get its replacement, Ariane-6, operational. As such, SpaceX got the business, since it is the cheapest and most reliable alternative.

The leaders in the 2023 launch race:

44 SpaceX
24 China
9 Russia
5 Rocket Lab

In the national rankings, American private enterprise now leads China in successful launches 50 to 24, and the entire world combined 50 to 41, with SpaceX by itself leads the entire world, excluding other American companies, 44 to 41.

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ESA looking to SpaceX to launch Euclid space telescope

9:02 am

Capitalism in space: Having lost its Soyuz launch vehicle for its Euclid space telescope because of the Russian invasion of the Ukraine, the European Space Agency (ESA) is now looking at SpaceX as a possible option.

At a meeting of NASA’s Astrophysics Advisory Council, Mark Clampin, director of the agency’s astrophysics division, said his understanding is that the European Space Agency was leaning towards launching its Euclid mission on a Falcon 9 in mid to late 2023.

NASA is a partner on Euclid, a space telescope that will operate around the Earth-sun L-2 Lagrange point 1.5 million kilometers from Earth to study dark energy, dark matter and other aspects of cosmology. The 2,160-kilogram spacecraft was to launch on a Soyuz rocket from French Guiana in 2023.

Europe has for years used its own rockets for its science missions. However, right now the Falcon 9 appears the only option. The last launches of Europe’s Ariane-5 rocket are already assigned, and the new Ariane-6 rocket has not yet flown, is behind schedule, and its early launches are also already reserved.

Nor does ESA have other options outside of SpaceX. Of the rockets powerful enough to do the job, ULA’s Atlas-5 is also being retired, and the Vulcan rocket is as yet unavailable. Blue Origin’s New Glenn is years behind schedule, with no clear idea when it will finally launch.

A final decision is expected soon. ESA could either go with SpaceX, or simply delay several years until Ariane-6 is flying.

If SpaceX gets the job however it will once again demonstrate the value of moving fast in a competitive environment. While its competitors have dithered and thus do not have their rockets ready, SpaceX has been flying steadily for years, so it gets the business.

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NASA instrument for European space telescope flawed and must be rebuilt

5:29 pm

The NASA instrument for Europe’s Euclid optical/near-infrared space telescope has been found defective and must be rebuilt, thus delaying the launch of the telescope by at least one year.

What interested me about this telescope is its goals and specifications:

Euclid is a two-ton space telescope selected by ESA in 2011 as a medium-class mission in its Cosmic Vision program of space science missions. The spacecraft features a 1.2-meter telescope with visible and near-infrared instruments to study dark energy and dark matter, which combined account for about 95 percent of the universe. Euclid will operate at the Earth-sun L-2 Lagrange point, 1.5 million kilometers from Earth, that is used by other infrared astronomy missions.

With a mirror about half the size of Hubble’s, this telescope will act as a partial replacement and back up for it. In fact, it will likely make numerous ground-breaking discoveries, as every optical telescope placed above the atmosphere has so far done.

Meanwhile, the article provided no information on the flaws, who built the flawed instrument, and who will pay for the delays its failure will cause.

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NASA has now agreed to contribute equipment and researchers to a European dark energy mission.

9:17 am

The check is in the mail: NASA has now agreed to contribute equipment and researchers to a European dark energy mission.

And why should Europe have any expectation that NASA will follow through? Europe’s ExoMars project was screwed badly when NASA pulled out last year. Nor was that the first time the U.S. government reneged on a deal with Europe.

Considering the fragile nature of the U.S. federal budget, I wouldn’t depend on anything from NASA or any U.S. government agency for the foreseeable future. And this includes the various private space companies such as SpaceX and Orbital Sciences that are using NASA subsidies to build their spaceships. Get those things built, and quickly! The government money could disappear very soon.

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