All posts by Tom

Supermoons to End Year

Supermoons end the year 2016.

16 October – 14 November – 14 December are the dates and the November supermoon is notable because it is the closest the moon will be to Earth until 25 November 2034.

I will repost this in November and December a couple days before the full moons.


Preparing For Launch

Soyuz Commander Sergey Ryzhikov and Flight Engineer Andrey Borisenko of Roscosmos and Flight Engineer Shane Kimbrough of NASA along with their backups, Alexander Misurkin and Nikolai Tikhonov of Roscosmos and Flight Engineer Mark Vande Hei of NASA are the group comprising the crew of ISS Expedition 49-50.

The group are actively preparing for launch at the Soyuz MS-02 to the International Space Station on 19 October from the Baikonur Cosmodrome.


Hershel Looks at Orion


Click the image for the annotated version.

Credit: ESA/NASA/JPL-Caltech

The original caption:

The dusty side of the Sword of Orion is illuminated in this striking infrared image from the European Space Agency’s Hershel Space Observatory.

This immense nebula is the closest large region of star formation, situated about 1,500 light years away in the constellation of Orion. The parts that are easily observed in visible light, known alternatively as the Orion Nebula or Messier 42, correspond to the light blue regions. This is the glow from the warmest dust, illuminated by clusters of hot stars that have only recently been born in this chaotic region.

The red spine of material running from corner to corner reveals colder, denser filaments of dust and gas that are scattered throughout the Orion nebula. In visible light this would be a dark, opaque feature, hiding the reservoir of material from which stars have recently formed and will continue to form in the future.

Herschel data from the PACS instrument observations, at wavelengths of 100 and 160 microns, is displayed in blue and green, respectively, while SPIRE 250-micron data is shown in red.

Within the inset image, the emission from ionized carbon atoms (C+), overlaid in yellow, was isolated and mapped out from spectrographic data obtained by the HIFI instrument. A version without the inset is also available.

Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. While the observatory stopped making science observations in April 2013, after running out of liquid coolant as expected, scientists continue to analyze its data. NASA’s Herschel Project Office is based at JPL. JPL contributed mission-enabling technology for two of Herschel’s three science instruments. The NASA Herschel Science Center, part of IPAC, supports the U.S. astronomical community. Caltech manages JPL for NASA.

A Planetary Nebula?


This doesn’t look like a typical planetary nebula it is.

From ESA:
The two spiral arms winding towards the bright centre might deceive you into thinking you are looking at a galaxy a bit like our Milky Way. But the object starring in this image is of a different nature: PK 329-02.2 is a ‘planetary nebula’ within our home galaxy.

Despite the name, this isn’t a planet either. Planetary nebula is a misnomer that came about because of how much nebulas resembled giant, gaseous planets when looked through a telescope in the 1700s. Rather, what we see in this image is the last breath of a dying star.

When stars like the Sun are nearing the end of their lives, they let go of their gaseous outermost layers. As these clouds of stellar material move away from the central star they can acquire irregular and complex shapes. This complexity is evident in the faint scattered gas you see at the centre of the image. But there is also beautiful symmetry in PK 329-02.2, as the two bright blue spiral arms perfectly align with the two stars at the centre of the nebula.

It may look like the spiral arms are connected, but it is the stars that are companions. They are part of a visual binary, though only the one at the upper right gave rise to the nebula. While the stars will continue to orbit each other for millions or billions of years, the nebula – and its spiral arms – will spread out from the centre and eventually fade away over the next few thousands of years.

This planetary nebula with spiral arms is also known as Menzel 2, after the US astronomer Donald Menzel who discovered it in the 1920s. It is located in Norma, a constellation in the Southern celestial hemisphere where you can also find Menzel 1 and 3, two ‘bipolar planetary nebulas’ (shaped like butterflies or hourglasses).

Hubble’s Wide Field and Planetary Camera 2 captured this image, which was processed using green, blue, red and infrared filters. Astrophotography-enthusiast Serge Meunier entered a version of this image into the 2012 Hubble’s Hidden Treasures image processing competition.

Copyright ESA/Hubble & NASA; Acknowledgement: Serge Meunier

Light on the Nightside


The shadow is getting shorter as Saturn nears the northern solstice. The moon is pretty easily seen at about 11:00.

NASA’s description:

NASA’s Cassini spacecraft looks down at the rings of Saturn from above the planet’s nightside. The darkened globe of Saturn is seen here at lower right, along with the shadow it casts across the rings.

The image shows that even on the planet’s night side, the rings remain in sunlight, apart from the portion that lies within Saturn’s shadow. The rings also reflect sunlight back onto the night side of the planet, making it appear brighter than it would otherwise appear.

Saturn’s small moon Prometheus (53 miles or 86 kilometers across) is faintly visible as a speck near upper left. The shadow of Saturn was once long enough to stretch to the orbit of Prometheus. But as northern summer solstice approaches, Saturn’s shadow no longer reaches that far (see PIA20498). So Prometheus will not move into the darkness of the planet’s shadow until the march of the seasons again causes the shadow to lengthen.

This view looks toward the sunlit side of the rings from about 41 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Aug. 14, 2016.

The view was obtained at a distance of approximately 870,000 miles (1.4 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 87 degrees. Image scale is 53 miles (86 kilometers) per pixel. Prometheus has been brightened by a factor of two to enhance its visibility.

Wharton Ridge

Here is an image taken of the western rim of Endeavour Crater on Mars. This image contains a portion of “Marathon Valley and “Wharton Ridge” and was taken in August 2016 by the rover Opportunity!


From the caption released with the image:

The full extent of Wharton Ridge is visible, with the floor of Endeavour Crater beyond it and the far wall of the crater in the distant background. Near the right edge of the scene is “Lewis and Clark Gap,” through which Opportunity crossed from Marathon Valley to “Bitterroot Valley” in September 2016.

Before the rover departed Marathon Valley, its panoramic camera (Pancam) acquired the component images for this scene on Aug. 30, 2016, during the 4,480th Martian day, or sol, of Opportunity’s work on Mars.

Opportunity’s science team chose the ridge’s name to honor the memory of Robert A. Wharton (1951-2012), an astrobiologist who was a pioneer in the use of terrestrial analog environments, particularly in Antarctica, to study scientific problems connected to the habitability of Mars. Over the course of his career, he was a visiting senior scientist at NASA Headquarters, vice president for research at the Desert Research Institute, provost at Idaho State University, and president of the South Dakota School of Mines and Technology.

The view spans from east-northeast at left to southeast at right. It merges exposures taken through three of the Pancam’s color filters, centered on wavelengths of 753 nanometers (near-infrared), 535 nanometers (green) and 432 nanometers (violet). It is presented in approximately true color.

Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

Like a Plasma Wake


This sounds something like an evolution of a wake to me. I could see the plasma, which I would guess would be rotating, coalesce into spherical masses or “balls”.

Here is the NASA description:
This four-panel graphic illustrates how the binary-star system V Hydrae is launching balls of plasma into space.

Panel 1 shows the two stars orbiting each other. One of the stars is nearing the end of its life and has swelled in size, becoming a red giant.

In panel 2, the smaller star’s orbit carries the star into the red giant’s expanded atmosphere. As the star moves through the atmosphere, it gobbles up material from the red giant that settles into a disk around the star.

The buildup of material reaches a tipping point and is eventually ejected as blobs of hot plasma along the star’s spin axis, as shown in panel 3.

This ejection process is repeated every eight years, which is the time it takes for the orbiting star to make another pass through the bloated red giant’s envelope, as shown in panel 4.