The subject of this Hubble Picture of the Week is a spiral galaxy in the constellation Virgo named NGC 5668. It is relatively near to us at 90 million light-years from Earth and quite accessible for astronomers to study with both space- and ground-based telescopes. At first blush, it doesn’t seem like a remarkable galaxy. It is around 90 000 light-years across, similar in size and mass to our own Milky Way galaxy, and its orientation nearly face-on to us shows open spiral arms made of cloudy, irregular patches.
One noticeable difference between the Milky Way galaxy and NGC 5668 is that this galaxy is forming new stars 60% more quickly. This fact belies a galaxy with churning clouds and flows of gas, inclement weather that forms excellent conditions for the formation of new stars! Two main drivers of star formation have been identified by astronomers. Firstly, this high-quality Hubble snapshot reveals a bar at the centre; it might look more like a slight oval shape than a real bar, but it appears to have impacted the galaxy’s star formation rate, as central bars do in many spiral galaxies. Secondly, high-velocity clouds of hydrogen gas have been tracked moving vertically between the disc of the galaxy and the spherical, faint halo which surrounds it. These can be produced by the strong stellar winds of hot, massive stars, and they contribute gas to new star-forming regions.
The enhanced star formation rate in NGC 5668 comes with a corresponding abundance of supernova explosions. Three have been spotted in the galaxy, in 1952, 1954 and 2004. In this image, Hubble was used to examine the surroundings of the Type II SN 2004G, seeking to study the kinds of stars that end their lives as this kind of supernova.
[Image Description: A spiral galaxy, seen up close and face-on. It is coloured yellow and glowing brightly at the oval-shaped centre, showing older and cooler stars, and it becomes bluer out to the edge of the disc where the stars are younger and hotter. It has a number of somewhat patchy spiral arms curling around, with sparkling areas where stars form. The black background can just be seen at the corners.]
Credits: ESA/Hubble & NASA, C. Kilpatrick; CC BY 4.0
Tags: NGC 5668 ESA European Space Agency Space Universe Cosmos Space Science Science Space Technology Tech Technology HST Hubble Space Telescope Galaxy Supernova NASA Creative Commons Stars Star Type II SN 2004G
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Annotated image of Digel Cloud 2S captured by Webb's NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument), with compass arrows, a scale bar, colour key, and graphic overlays for reference.
The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).
The scale bar is labelled in light-years and arcseconds. One light-year is equal to about 9.46 trillion kilometres. One arcsecond is equal to 1/3600 of one degree of arc (the full Moon has an angular diameter of about 0.5 degrees). The actual size of an object that covers one arcsecond on the sky depends on its distance from the telescope.
This image shows invisible near- and mid-infrared wavelengths of light that have been translated into visible-light colours. The colour key shows which NIRCam and MIRI filters were used when collecting the light. The colour of each filter name is the visible light colour used to represent the infrared light that passes through that filter.
In the main cluster are five white arrows, which highlight the paths of five protostar jets.
Credits: NASA, ESA, CSA, STScI, M. Ressler (NASA-JPL); CC BY 4.0
Tags: ESA European Space Agency Space Universe Cosmos Space Science Science JWST Webb James Webb James Webb Space Space Telescope CSA Canadian Space Agency NASA WebbESA ESAWebb Extreme Outer Galaxy Digel Cloud 2 Infrared Mid-InfraRed Instrument Digel Clouds
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The NASA/ESA/CSA James Webb Space Telescope has observed the very outskirts of our Milky Way galaxy. Known as the Extreme Outer Galaxy, this region is located more than 58 000 light-years from the galactic centre.
A team of scientists used Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to image four selected regions within two molecular clouds known as Digel Clouds 1 and 2: 1A, 1B, 2N, and 2S. These Webb observations enable scientists to study star formation in the outer Milky Way at the same level of detail as observations of star formation in our own solar neighbourhood.
Thanks to its high sensitivity and sharp resolution, Webb was able to capture these areas, which are hosts to star clusters undergoing bursts of star formation, in unprecedented detail. Some of the details revealed by these data include components of the clusters such as very young protostars, outflows and jets, and distinctive nebular structures.
In the case of Cloud 2S, shown here, Webb revealed a luminous main cluster that contains newly formed stars. This dense area is quite active and several stars are emitting extended jets of material along their poles. Additionally, while scientists previously suspected a sub-cluster might be present within the cloud, Webb’s imaging capabilities confirmed its existence for the first time. Webb’s data reveal that there are multiple jets shooting out in different directions from this cluster of stars.
This Webb imagery of the Extreme Outer Galaxy and the Digel Clouds is just a starting point for the team. They intend to revisit this Milky Way outpost to find answers to a variety of current questions, including the relative abundance of stars of various masses within Extreme Outer Galaxy star clusters. This is a measurement that would help astronomers understand how a particular environment can influence different types of stars during their formation.
Though the story of star formation is complex and some chapters are still shrouded in mystery, Webb is gathering clues and helping astronomers unravel this intricate tale.
These findings have been published in the Astronomical Journal.
The observations were taken as part of Guaranteed Time Observation program 1237.
[Image description: At centre is a compact star cluster composed of luminous red, blue, and white points of light. Faint jets with clumpy, diffuse material extend in various directions from the bright cluster. Above and to the right is a smaller cluster of stars. Translucent red wisps of material stretch across the scene, though there are patches and a noticeable gap in the top left corner that reveal the black background of space. Background galaxies are scattered across this swath of space, appearing as small blue-white and orange-white dots or fuzzy, thin discs. There is one noticeably larger blue-white point with diffraction spikes, a foreground star in the upper right.]
Credits: NASA, ESA, CSA, STScI, M. Ressler (NASA-JPL); CC BY 4.0
Tags: Digel Cloud 2 ESA European Space Agency Space Universe Cosmos Space Science Science JWST Webb James Webb James Webb Space Space Telescope CSA Canadian Space Agency NASA WebbESA ESAWebb Extreme Outer Galaxy Infrared Mid-InfraRed Instrument Digel Clouds
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The team at NASA’s Kennedy Space Center in Florida, USA, unboxed ESA’s third European Service Module earlier this week. This powerhouse, boasting 33 engines, is destined for the Artemis III mission, where it will provide life support for the astronauts and propel NASA’s Orion spacecraft in deep space. The module was built with contributions from over 20 companies across more than 10 European countries.
During this summer, the European Service Module left the integration halls of Airbus in Bremen, Germany and sailed across the Atlantic Ocean on board Canopée, the world’s first hybrid wind-powered commercial cargo vessel. Eleven days later, the ship and its precious cargo arrived safely in Port Canaveral, ready to meet the other modules of the NASA Orion spacecraft that will carry astronauts back towards the Moon.
In the next weeks, engineers will connect the third European Service Module with the Crew Module Adapter to form the complete service module of the Orion vehicle. ESA’s second European Service Module underwent the same process last year; it is now connected to its crew module and is in the later stages of testing ahead of the Artemis II mission next year.
Credits: NASA
Tags: Artemis Artemis III NASA ESM European Service Module Orion Orion spacecraft Forward to the Moon To the Moon Moon Rocket Kennedy Space Center KSC Florida USA US United States Rocket SLS Space Launch System
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When ESA’s Hera asteroid mission for planetary defence touched down at its Florida launch site in its Antonov An-124 transporter, the mission’s two shoebox-sized CubeSats travelled with it. This is the moment the Milani and Juventas CubeSats made it down to the ground on the morning of 3 September.
The two CubeSats have since undergone functional testing – to check no damage was sustained from their travels – then been fuelled, and are now integrated into the main spacecraft, in readiness for a planned launch by SpaceX Falcon 9 from Cape Canaveral Space Force Station in early October.
Seen left is the Milani CubeSat in its container, produced for ESA by Tyvak International in Italy, with the Juventas CubeSat from GomSpace in Luxembourg to the right.
The Milani CubeSat hosts a multispectral imager to map surface mineralogy as well as a dust surveyor. Juventas carries a radar instrument, to perform the first radar probe of an asteroid’s internal structure, along with a gravity-detecting gravimeter.
The CubeSats have been stowed in their ‘Deep Space Deployers’ on Hera’s top-side Asteroid Deck, which will stow them safely until they are ready to be deployed one at a time in the vicinity of the mission’s target Didymos binary asteroid.
About Hera
Hera is ESA’s first mission for planetary defence. Due for launch in October this year, Hera will fly to the Didymos binary asteroid system in deep space to perform a close-up survey of the Dimorphos moonlet in orbit around the primary body. The Great-Pyramid-sized Dimorphos is already historic, as the first Solar System object to have its orbit changed by human activity, by the 2022 impact of NASA’s DART mission.
Hera is intended to gather crucial missing data about Dimorphos for scientists, to turn DART’s grand-scale experiment into a well-understood and potentially repeatable planetary defence technique. To increase its yield of data, Hera carries with it ESA’s first deep space CubeSats, carrying additional instruments and planned to fly closer to the asteroid’s surface than the main spacecraft, before eventually landing.
Credits: ESA
Tags: ESA European Space Agency Space Universe Cosmos Space Science Science Space Technology Tech Technology CubeSats Hera Juventas CubeSat Milani CubeSat Milani Juventas
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