Here is the latest Space to Ground weekly report from NASA on activities related to the International Space Station:
Here is a longer video showing the SpaceX Dragon cargo vehicle departing from the ISS last Sunday:
US astronaut Mark Vande Hei recently arrived on the station to take on his role as Expedition 53 Flight Engineer. In this video he “fielded questions about life and work on the orbital outpost during an in-flight educational event Sept. 18 with students from the Pine River-Backus schools in Pine River, Minnesota”.
This artist’s impression shows the binary asteroid 288P, located in the main asteroid belt between the planets Mars and Jupiter. The object is unique as it is a binary asteroid which also behaves like a comet. The comet-like properties are the result of water sublimation, caused by the heat of the Sun. The orbit of the asteroids is marked by a blue ellipse. [Larger images]With the help of the NASA/ESA Hubble Space Telescope, a German-led group of astronomers have observed the intriguing characteristics of an unusual type of object in the asteroid belt between Mars and Jupiter: two asteroids orbiting each other and exhibiting comet-like features, including a bright coma and a long tail. This is the first known binary asteroid also classified as a comet. The research is presented in a paper published in the journal Nature this week.
In September 2016, just before the asteroid 288P made its closest approach to the Sun, it was close enough to Earth to allow astronomers a detailed look at it using the NASA/ESA Hubble Space Telescope [1].
This artist’s impression shows the binary main-belt comet 288P. From a distance the comet-like features of the system can clearly be seen: among them, the bright coma surrounding both components of the system and the long tail of dust and water pointing away from from the Sun. Only a closer look reveals the two components of the system: two asteroids circling each other on an eccentric orbit. Credit: ESA/Hubble, L. Calçada, M. Kornmesser
The images of 288P, which is located in the asteroid belt between Mars and Jupiter, revealed that it was actually not a single object, but two asteroids of almost the same mass and size, orbiting each other at a distance of about 100 kilometres. That discovery was in itself an important find; because they orbit each other, the masses of the objects in such systems can be measured.
This set of images from the ESA/NASA Hubble Space Telescope reveals two asteroids with comet-like features orbiting each other. These include a bright halo of material, called a coma, and a long tail of dust. The asteroid pair, called 288P, was observed in September 2016 just before the asteroid made its closest approach to the Sun. These images reveal ongoing activity in the binary system. The apparent movement of the tail is a projection effect due to the relative alignment between the Sun, Earth, and 288P changing between observations. The tail orientation is also affected by a change in the particle size. Initially, the tail was pointing towards the direction where comparatively large dust particles (about 1 millimetre in size) were emitted in late July. However, from 20 September 2016 onwards, the tail began to point in the opposite direction from the Sun where small particles (about 10 microns in size) are blown away from the nucleus by radiation pressure. [Larger images]But the observations also revealed ongoing activity in the binary system.
“We detected strong indications of the sublimation of water ice due to the increased solar heating — similar to how the tail of a comet is created,”
Understanding the origin and evolution of main-belt comets — asteroids orbiting between Mars and Jupiter that show comet-like activity — is a crucial element in our understanding of the formation and evolution of the whole Solar System. Among the questions main-belt comets can help to answer is how water came to Earth [2]. Since only a few objects of this type are known, 288P presents itself as an extremely important system for future studies.
This time-lapse video, assembled from a set of ESA/NASA Hubble Space Telescope images, reveals two asteroids with comet-like features orbiting each other. The asteroid pair, called 288P, was observed in September 2016, just before the asteroid made its closest approach to the Sun.
The various features of 288P — wide separation of the two components, near-equal component size, high eccentricity and comet-like activity — also make it unique among the few known wide asteroid binaries in the Solar System. The observed activity of 288P also reveals information about its past, notes Agarwal:
“Surface ice cannot survive in the asteroid belt for the age of the Solar System but can be protected for billions of years by a refractory dust mantle, only a few metres thick.”
From this, the team concluded that 288P has existed as a binary system for only about 5000 years. Agarwal elaborates on the formation scenario:
“The most probable formation scenario of 288P is a breakup due to fast rotation. After that, the two fragments may have been moved further apart by sublimation torques.”
The fact that 288P is so different from all other known binary asteroids raises some questions about whether it is not just a coincidence that it presents such unique properties. As finding 288P included a lot of luck, it is likely to remain the only example of its kind for a long time.
“We need more theoretical and observational work, as well as more objects similar to 288P, to find an answer to this question,” concludes Agarwal.
Notes
[1] Like any object orbiting the Sun, 288P travels along an elliptical path, bringing it closer and further away to the Sun during the course of one orbit.
[2] Current research indicates that water came to Earth not via comets, as long thought, but via icy asteroids.
This image depicts the two areas where most of the asteroids in the Solar System are found: the asteroid belt between Mars and Jupiter, and the trojans, two groups of asteroids moving ahead of and following Jupiter in its orbit around the Sun. The binary asteroid 288P is part of the asteroid belt. [Larger images]
This ALMA image reveals much finer structure in the U Antliae shell than has previously been possible. Around 2700 years ago, U Antliae went through a short period of rapid mass loss. During this period of only a few hundred years, the material making up the shell seen in the new ALMA data was ejected at high speed. Examination of this shell in further detail also shows some evidence of thin, wispy clouds known as filamentary substructures. [Larger images]Astronomers have used ALMA to capture a strikingly beautiful view of a delicate bubble of expelled material around the exotic red star U Antliae. These observations will help astronomers to better understand how stars evolve during the later stages of their life-cycles.
In the faint southern constellation of Antlia (The Air Pump) the careful observer with binoculars will spot a very red star, which varies slightly in brightness from week to week. This very unusual star is called U Antliae and new observations with the Atacama Large Millimeter/submillimeter Array (ALMA) are revealing a remarkably thin spherical shell around it.
Astronomers have used ALMA to capture a strikingly beautiful view of a delicate bubble of expelled material around the exotic red star U Antliae. These observations will help astronomers to better understand how stars evolve during the later stages of their life-cycles. This short podcast takes a look at this important new result and what it means. Credit: ESO.
U Antliae [1] is a carbon star, an evolved, cool and luminous star of the asymptotic giant branch type. Around 2700 years ago, U Antliae went through a short period of rapid mass loss. During this period of only a few hundred years, the material making up the shell seen in the new ALMA data was ejected at high speed. Examination of this shell in further detail also shows some evidence of thin, wispy gas clouds known as filamentary substructures.
The data collected with ALMA are not just a single image, but a three-dimensional dataset (a data cube) with each slice being observed at a slightly different wavelength. Because of the Doppler effect, different slices of the data cube show images of gas moving at different speeds towards or away from the observer. By displaying different velocities we can cut this cosmic bubble into virtual slices just as we do in computer tomography of a human body. Credit: ALMA (ESO/NAOJ/NRAO)/F. Kerschbaum
This spectacular view was only made possible by the unique ability to create sharp images at multiple wavelengths that is provided by the ALMA radio telescope, located on the Chajnantor Plateau in Chile’s Atacama Desert. ALMA can see much finer structure in the U Antliae shell than has previously been possible.
This video sequence takes the viewer on an imaginary journey from Earth to the red and ageing star U Antliae. Near the start we see the Moon briefly and later we pass many stars that are closer to Earth than the final goal of the journey, a rare carbon star about 900 light-years away. Credit: ESO/spaceengine.org
The new ALMA data are not just a single image; ALMA produces a three-dimensional dataset (a data cube) with each slice being observed at a slightly different wavelength. Because of the Doppler Effect, this means that different slices of the data cube show images of gas moving at different speeds towards or away from the observer. This shell is also remarkable as it is very symmetrically round and also remarkably thin. By displaying the different velocities we can cut this cosmic bubble into virtual slices just as we do in computer tomography of a human body.
This image was created from ALMA data on the unusual red carbon star U Antliae and its surrounding shell of material. The colours show the motion of the glowing material in the shell along the line of sight to the Earth. Blue material lies between us and the central star, and is moving towards us. Red material around the edge is moving away from the star, but not towards the Earth. For clarity this view does not include the material on the far side of the star, which is receding from us in a symmetrical manner. [Large image.]Understanding the chemical composition of the shells and atmospheres of these stars, and how these shells form by mass loss, is important to properly understand how stars evolve in the early Universe and also how galaxies evolved. Shells such as the one around U Antliae show a rich variety of chemical compounds based on carbon and other elements. They also help to recycle matter, and contribute up to 70% of the dust between stars.
Notes [1] The name U Antliae reflects the fact that it is the fourth star that changes its brightness to be found in the constellation of Antlia (The Air Pump). The naming of such variable stars followed a complicated sequence as more and more were found and is explained here.
This image from the Digitized Sky Survey 2 shows the very red carbon star U Antliae and its surroundings. [ Larger Images.]
A look at the history and status today of rendering the cosmos in paintings, drawings, digital media, and sculptures: The Art of Space Art – The Paris Review
We can trace the sparks for today’s space art as far back as Jules Verne, who published his novel Off on a Comet in 1877 with a painting by Paul Dominique Philippoteaux that imagined Saturn as more than just points of light in the sky. Before that, no one was depicting other planets as places you could stand on—places you could look up from rather than to. By the end of the nineteenth century, the astronomer Percival Lowell had begun to publish his series of illustrated books that reflected his claim that the lines he saw on Mars were artificial canals, the work of intelligent Martians. The public imagination quickened. In 1937, the French artist, author, and astronomer Lucien Rudaux published a book illustrated with what he believed the surfaces of other planets to look like. The book caught the attention of [Chesley] Bonestell, who had been working as a special effects artist in Hollywood. He began creating realistic paintings from the perspective of someone standing on the surface of the moon or Titan, publishing his work in Life in 1944. He became the most prominent name in the field, his vision bolstered by the work of a handful of iconic contemporaries such as Ludek Pesek, an artist and astronomer who’d also been inspired by Rudaux.
Today there are new inspirations and new outlets for space art:
Multiple artists I spoke with hoped that SpaceX and its competitors would widen the market for high-profile space art beyond NASA, especially since there are only so many journal covers to go around. The genre is also finally gaining acceptance in the fine-arts world; galleries that once dismissed the genre as merely illustrative are now opening their doors to space artists. One IAAA member is rendering a series of deep-space images—nebulae, galaxies, images inspired by Hubble—as quilts.
A wide-ranging survey exhibition, it brings together contemporary artists from across the Americas who have tapped into science fiction’s capacity to imagine new realities, both utopian and dystopian. Science fiction offers a unique artistic landscape in which to explore the colonial enterprise that shaped the Americas and to present alternative perspectives speculating on the past and the future. In the works featured in the exhibition, most created in the last two decades, artists employ the imagery of science fiction to suggest diverse modes of existence and represent “alienating” ways of being in the world. Drawing on UCR’s strong faculty and collections in science fiction, the exhibition offers a groundbreaking account of the intersections among science fiction, techno-culture, and the visual arts.
[] Beatriz Cortez – 2017 – “This sculpture takes the form of a space capsule that brings together references to space travel, local construction techniques, and Indigenous Maya architecture. The architectural shell features embellishments that invoke the river rocks commonly used in the construction of contemporary homes throughout Southern California. ” Continue…
