New space elevator magazine and a new documentary available on line

The International Space Elevator Consortium (ISEC) just released its latest newsletter: ISEC eNewsletter – December 2015.

Included is an announcement about their new magazine: Via Ad Astra – The Space Elevator Magazine –

Volume 1 / Number 1 of Via Ad Astra (Road to the Stars), the new Space Elevator Magazine from the International Space Elevator Consortium is now available!

This magazine contains an interview with Yuri Artsutanov (the Russian engineer credited with inventing the modern day concept of the space elevator), a reprint of an article by Jerome Pearson (the American engineer who independently proposed the modern day concept of the space elevator), articles on the Space Elevator Games, International Law & the Space Elevator and much, much more.

Print copies of this magazine are now available from the ISEC Store for only $11.99 as well as pdf versions, available for only $1.99.

The newsletter also points to a Kickstarter funded documentary about space elevators. The 74 minute long feature Sky Line was released in November and is available for purchase on line: Space Elevator Docu ‘Sky Line’ Hits Vod November 20; THX Hires New CEO – Deadline.

In 1979, Arthur C. Clarke wrote a novel about an elevator that goes to outer space. SKYLINE is the story of the people who intend to build it. From scientific gatherings to NASA’s high-stakes Space Elevator Games, the film follows the major players working to make the concept a reality. Some believe it will solve the energy crisis; some want easier access to raw materials in space; some just want to gaze down upon the Earth. For all of them, the space elevator is more than just science fiction: it’s an achievable goal.

Here is the trailer:

ESO: ALMA antennas find signs of new planets in discs around young stars

A new report from ESO (European Southern Observatory):

ALMA Reveals Planetary Construction Sites
New evidence for young planets in discs around young stars

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found the clearest indications yet that planets with masses several times that of Jupiter have recently formed in the discs of gas and dust around four young stars. Measurements of the gas around the stars also provide additional clues about the properties of those planets.

Artist’s impression of a transitional disc around a young star. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs.
Artist’s impression of a transitional disc around a young star. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. Credit: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser

Planets are found around nearly every star, but astronomers still do not fully understand how — and under what conditions — they form. To answer such questions, they study the rotating discs of gas and dust present around young stars from which planets are built. But these discs are small and far from Earth, and the power of ALMA was needed for them to reveal their secrets.

Schematic view of a transitional disc around a young star. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. This schematic diagram shows how the dust (brown) and gas (blue) is distributed around the star, and how a young planet is clearing the central gap.
Schematic view of a transitional disc around a young star. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. This schematic diagram shows how the dust (brown) and gas (blue) is distributed around the star, and how a young planet is clearing the central gap.

A special class of discs, called transitional discs, have a surprising absence of dust in their centres, in the region around the star. Two main ideas have been put forward to explain these mysterious gaps. Firstly, the strong stellar winds and intense radiation could have blown away or destroyed the encircling material [1]. Alternatively, massive young planets in the process of formation could have cleared the material as they orbit the star [2].

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. Credit: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser

The unparalleled sensitivity and image sharpness of ALMA have now allowed the team of astronomers, led by Nienke van der Marel from the Leiden Observatory in the Netherlands to map the distribution of gas and dust in four of these transitional discs better than ever before [3]. This in turn has allowed them to choose between the two options as the cause of the gaps for the first time.

ALMA imaging of the transitional disc HD 135344B. This ALMA image combines a view of the dust around the young star HD 135344B (orange) with a view of the gaseous material (blue). The smaller hole in the inner gas is a telltale sign of the presence of a young planet clearing the disc. The bar at the bottom of the image indicates the diameter of the orbit of Neptune in the Solar System (60 AU).
ALMA imaging of the transitional disc HD 135344B. This ALMA image combines a view of the dust around the young star HD 135344B (orange) with a view of the gaseous material (blue). The smaller hole in the inner gas is a telltale sign of the presence of a young planet clearing the disc. The bar at the bottom of the image indicates the diameter of the orbit of Neptune in the Solar System (60 AU).

The new images show that there are significant amounts of gas within the dust gaps [4]. But to the team’s surprise, the gas also possessed a gap, up to three times smaller than that of the dust.

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. Credit: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser

This could only be explained by the scenario in which newly formed massive planets have cleared the gas as they travelled around their orbits, but trapped the dust particles further out [5].

Previous observations already hinted at the presence of gas inside the dust gaps,” explains Nienke van der Marel. “But as ALMA can image the material in the entire disc in much greater detail than other facilities, we could rule out the alternative scenario. The deep gap points clearly to the presence of planets with several times the mass of Jupiter, creating these caverns as they sweep through the disc.

Remarkably, these observations were conducted utilising just one tenth of the current resolving power of ALMA, as they were performed whilst half of the array was still under construction on the Chajnantor Plateau in northern Chile.

ALMA imaging of the transitional disc DoAr 44. This ALMA image combines a view of the dust around the young star DoAr 44 (orange) with a view of the gaseous material (blue). The smaller hole in the inner gas is a telltale sign of the presence of a young planet clearing the disc. The bar at the bottom of the image indicates the diameter of the orbit of Neptune in the Solar System (60 AU).
ALMA imaging of the transitional disc DoAr 44. This ALMA image combines a view of the dust around the young star DoAr 44 (orange) with a view of the gaseous material (blue). The smaller hole in the inner gas is a telltale sign of the presence of a young planet clearing the disc. The bar at the bottom of the image indicates the diameter of the orbit of Neptune in the Solar System (60 AU).

Further studies are now needed to determine whether more transitional discs also point towards this planet-clearing scenario, although ALMA’s observations have, in the meantime, provided astronomers with a valuable new insight into the complex process of planetary formation.

All the transitional discs studied so far that have large dust cavities also have gas cavities. So, with ALMA, we can now find out where and when giant planets are being born in these discs, and compare these results with planet formation models,” says Ewine van Dishoeck, also of Leiden University and the Max Planck Institute for Extraterrestrial Physics in Garching [6]. “Direct planetary detection is just within reach of current instruments, and the next generation telescopes currently under construction, such as the European Extremely Large Telescope, will be able to go much further. ALMA is pointing out where they will need to look.”

Notes

[1] This process, which clears the dust and gas from the inside out, is known as photoevaporation.

[2] Such planets are difficult to observe directly (eso1310) and previous studies at millimetre wavelengths (eso1325) have failed to achieve a sharp view of their inner, planet-forming zones where these different explanations could be put to the test. Other studies (eso0827) could not measure the bulk of the gas in these discs.

[3] The four targets of these investigations were SR 21, HD 135344B (also known as SAO 206462), DoAr 44 and Oph IRS 48.

[4] The gas present in transitional discs consists primarily of hydrogen, and is traced through observations of the carbon monoxide — or CO — molecule.

[5] The process of dust trapping is explained in an earlier release (eso1325).

[6] Other examples include the HD 142527 (eso1301 and here) and J1604-2130 transitional discs.

Space Music: Suzerain covers ‘Space Oddity’ to mark Tim Peake’s spaceflight

The band Suzerain released a cover of David Bowie’s song Space Oddity in honour of Astronaut Tim Peake‘s launch to the International Space Station on Tuesday: Space Oddity (David Bowie Cover) by SUZERAIN

Peake is the first “official” UK government supported astronaut to go to space. Here is a video of his Soyuz rocket lifting off from the Baikonur Cosmodrome in Kazakhstan.  In the Soyuz spacecraft with Peake were Expedition 46-47 Soyuz Commander Yuri Malenchenko of the Russian Federal Space Agency (Roscosmos) and NASA Flight Engineer Tim Kopra

And here is a video of the Soyuz spacecraft approaching and docking with the ISS six hours after launch: