All posts by Tom

Ready or Not Here Comes Juno

Ready or not, Juno is about to sweep to 4,200 km / 2,500 miles above the clouds of Jupiter at a velocity of 208,000 km/hr  or 130,000 miles/hr. The encounter will occur Saturday at 12:51 UTC.

The image below was taken on 23 August at a distance of 4.4 million km / 2.8 million miles as Juno continued towards Jupiter on this initial orbit.


The caption released with the image:

This dual view of Jupiter was taken on August 23, when NASA’s Juno spacecraft was 2.8 million miles (4.4 million kilometers) from the gas giant planet on the inbound leg of its initial 53.5-day capture orbit.

The image on the left is a color composite taken with Junocam’s visible red, green, and blue filters. The image on the right was also taken by JunoCam, but uses the camera’s infrared filter, which is sensitive to the abundance of methane in the atmosphere. Bright features like the planet’s Great Red Spot are higher in the atmosphere, and so have less of their light absorbed by the methane.

NASA’s Jet Propulsion Laboratory, Pasadena, Calif., manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed at NASA’s Marshall Space Flight Center in Huntsville, Ala. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of the California Institute of Technology in Pasadena.

A Real Goldilocks Planet

WOW!  Pretty excellent work from the ESO!

A review of the data from shows  tiny Doppler shifts indicate the presence of a planet with a mass at least 1.3 times that of the Earth, orbiting around Proxima Centauri and just 7 million kilometres/ 4.3 million miles and that’s  only 5% of the Earth-Sun distance.  The orbital period (that’s a year) of the planet is 11.2 DAYS!

Yes, for Proxima Centauri that is still in the habitable zone.  Proxima Centauri is around 8.25 light-years away far enough to make further investigation difficult.

Difficult is not impossible. . . stay tuned,  as they say on the television.

ESO Video

Polaris Flare


From ESA and the Planck Collaboration:

This image from ESA’s Planck satellite appears to show something quite ethereal and fantastical: a sprite-like figure emerging from scorching flames and walking towards the left of the frame, its silhouette a blaze of warm-hued colours.

This fiery illusion is actually a celestial feature named the Polaris Flare. This name is somewhat misleading; despite its moniker, the Polaris Flare is not a flare but a 10 light-year-wide bundle of dusty filaments in the constellation of Ursa Minor (The Little Bear), some 500 light-years away.

The Polaris Flare is located near the North Celestial Pole, a perceived point in the sky aligned with Earth’s spin axis. Extended into the skies of the northern and southern hemispheres, this imaginary line points to the two celestial poles. To find the North Celestial Pole, an observer need only locate the nearby Polaris (otherwise known as the North Star or Pole Star), the brightest star in the constellation of Ursa Minor.

Some of the secrets of the Polaris Flare were uncovered when it was observed by ESA’s Herschel some years ago. Using a combination of such Herschel observations and a computer simulation, scientists think that the Polaris Flare filaments could have been formed as a result of slow shockwaves pushing their way through a dense interstellar cloud, an accumulation of cold cosmic dust and gas sitting between the stars of our Galaxy.

These shockwaves, reminiscent of the sonic booms formed by fast sound waves here on Earth, would have been themselves triggered by nearby exploding stars that disrupted their surroundings as they died, triggering cloud-wide waves of turbulence

These shockwaves, reminiscent of the sonic booms formed by fast sound waves here on Earth, were themselves triggered by nearby exploding stars that disrupted their surroundings as they died, triggering cloud-wide waves of turbulence. These waves swept up the gas and dust in their path, sculpting the material into the snaking filaments we see.

This image is not a true-colour view, nor is it an artistic impression of the Flare, rather it comprises observations from Planck, which operated between 2009 and 2013. Planck scanned and mapped the entire sky, including the plane of the Milky Way, looking for signs of ancient light (known as the cosmic microwave background) and cosmic dust emission. This dust emission allowed Planck to create this unique map of the sky – a magnetic map.

The relief lines laced across this image show the average direction of our Galaxy’s magnetic field in the region containing the Polaris Flare. This was created using the observed emission from cosmic dust, which was polarised (constrained to one direction). Dust grains in and around the Milky Way are affected by and interlaced with the Galaxy’s magnetic field, causing them to align preferentially in space. This carries through to the dust’s emission, which also displays a preferential orientation that Planck could detect.

The emission from dust is computed from a combination of Planck observations at 353, 545 and 857 GHz, whereas the direction of the magnetic field is based on Planck polarisation data at 353 GHz. This frame has an area of 30 x 30º on the sky, and the colours represent the intensity of dust emission.

Earth 50 Years Ago


50 years ago today the Lunar Orbiter 1 took the first picture of Earth from the moon. Lunar Orbiter 1 was launched on 10 August 1966 and returned 42 high-resolution and 187 medium-resolution frames were taken and transmitted to Earth covering over 5 million square kilometers of the Moon’s surface. This image was taken on 23 August 1966 at 16:35 GMT.

More about Lunar Orbiter 1

Image: NASA via Wikimedia

Contrasting Dione


Cassini continues to amaze.  Such a good value IMHO.

From NASA:

Dione reveals its past via contrasts in this view from NASA’s Cassini spacecraft. The features visible here are a mixture of tectonics — the bright, linear features — and impact cratering — the round features, which are spread across the entire surface.

Tectonic features tell the story of how Dione (698 miles or 1,123 kilometers across) has been heated and cooled since its formation, and scientists use those clues to piece together the moon’s past. Impact craters are evidence of external debris striking the surface, and thus they tell about the environment in which the moon has existed over its history.

This view looks toward the trailing hemisphere of Dione. North on Dione is up. The image was taken in visible light with the Cassini narrow-angle camera on April 11, 2015.

The view was obtained at a distance of approximately 68,000 miles (110,000 kilometers) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 28 degrees. Image scale is 2,165 feet (660 meters) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit and The Cassini imaging team homepage is at

Credit: NASA/JPL-Caltech/Space Science Institute

A Look Around Curiosity

Here’s a look around Curiosity, or the Mars Science Laboratory on Mars.  For two minutes you can look around the scene by using the arrows at the top left of the video or just “clicking and dragging” your way around.  Running out of time is no problem just replay the video (or whatever you would call this).

The scene is from a location called Murray Buttes and most of the features are labeled.  The rover is not visible in this MastCam product.

For scale The dark, flat-topped mesa seen to the left of the rover’s arm is about 50 feet (about 15 meters) high and, near the top, about 200 feet (about 60 meters) wide according to NASA.

I was looking at the panorama and thought how completely quiet it must be up there and what it would sound like to try and get an echo off the buttes. The echo time lag of course depends on the speed of sound on Mars. Looking around on the web quickly reveals the speed of sound on Mars is about 244.4 m/s or 801.3 ft/s compared to 340 m/sec or 1115 ft/sec on Earth. So the echo would take nearly 25 percent longer to return on Mars than on Earth.


Speed of sound on Mars
Speed of sound on Earth

The Orbits of Rosetta

ESA gives us this visualization of Rosetta’s journey. The video gives us a pretty good sense of the journey and how exacting the planning was and what it will be in the future, although the final bits of the journey were not completely finalized until after this visualization was made.

The trajectory shown in this animation is created from real data, but the comet rotation is not. An arrow indicates the direction to the Sun as the camera viewpoint changes during the animation. — ESA

I am always am amazed how ESA can make the very difficult look easy.


RS-25 Testing Continues

On 18 August an upgraded shuttle engine was tested at NASA’s Stennis Space Center.

This particular firing, in addition to the pressure and temperature conditions, tested a new engine controller which monitors engine status and communicates between the rocket and the engine.

This is the third in a series of six tests for the RS-25 working towards a 2018 test flight. The engines will eventually will be a package of four and will provide the power to put space travelers on course to Mars.

EVA to Install a New Docking Port

This morning there will be a spacewalk outside the International Space Station to install a new docking port delivered on a previous cargo mission by the SpaceX Dragon cargo ship.

The new port is necessary for the Americans to send astronauts to the station from their own soil, something that has not happened since the end of the Space Shuttle program.

The EVA begins at 12:05 UTC with coverage starting at 10:30 UTC. Below you should find a live stream so you can follow along.