All posts by Tom

The Big Picture

The United States launched its first satellite on this day 60 years ago – 31 January 1958.

The Explorer 1 satellite was put into an orbit that orbited the Earth for a little more than 12-years and completing 58,000 orbits before interfacing with the atmosphere and burning up on 31 March 1970.

This film is from 1958:

Open Cluster Gaia 1

Look what Gaia found! Nice job with the image Mr. Kaiser and nice job to Gaia for pointing this out.

Image: H. Kaiser / ESA

Original caption: If you gazed at the night sky over the past few weeks, it is possible that you stumbled upon a very bright star near the Orion constellation. This is Sirius, the brightest star of the entire night sky, which is visible from almost everywhere on Earth except the northernmost regions. It is, in fact, a binary stellar system, and one of the nearest to our Sun – only eight light-years away.

Known since antiquity, this star played a key role for the keeping of time and agriculture in Ancient Egypt, as its return to the sky was linked to the annual flooding of the Nile. In Ancient Greek mythology, it represented the eye of the Canis Major constellation, the Great Dog that diligently follows Orion, the Hunter.

Dazzling stars like Sirius are both a blessing and a curse for astronomers. Their bright appearance provides plenty of light to study their properties, but also outshines other celestial sources that happen to lie in the same patch of sky.

This is why Sirius has been masked in this picture taken by amateur astronomer Harald Kaiser on 10 January from Karlsruhe, a city in the southwest of Germany.

Once the glare of Sirius is removed, an interesting object becomes visible to its left: the stellar cluster Gaia 1, first spotted last year using data from ESA’s Gaia satellite.

Gaia 1 is an open cluster – a family of stars all born at the same time and held together by gravity – and it is located some 15 000 light-years away. Its chance alignment next to nearby, bright Sirius kept it hidden to generations of astronomers that have been sweeping the heavens with their telescopes over the past four centuries. But not to the inquisitive eye of Gaia, which has been charting more than a billion stars in our Milky Way galaxy.

Mr Kaiser heard about the discovery of this cluster during a public talk on the Gaia mission and zealously waited for a clear sky to try and image it using his 30 cm-diameter telescope. After covering Sirius on the telescope sensor – creating the dark circle on the image – he succeeded at recording some of the brightest stars of the Gaia 1 cluster.

Gaia 1 is one of two previously unknown star clusters that have been discovered by counting stars from the first set of Gaia data, which was released in September 2016. Astronomers are now looking forward to Gaia’s second data release, planned for 25 April, which will provide vast possibilities for new, exciting discoveries.

More information about opportunities for amateur astronomers to follow up on Gaia observations here.

The Super Blue Blood Moon

It’s all about the name, what’s with that?

“Super” comes from the proximity of the Moon to Earth. The Moon this time around is about as close as it can be to Earth when it is full. I believe the previous full moon was about 1,000 km closer than this one.

“Blue” comes from the second definition of a Blue moon and any place I look this up the definitions seem to be in the same order. I like to call them Type 1 and Type 2:

1. The third Full Moon in an astronomical season with four Full Moons (versus the usual three).
2. The second Full Moon in a month with two Full Moons.

We will get another “Type 2” blue moon in 2018 occurring in March. The next “Type 1” blue moon happens next year in May.

and finally

“Blood” is for the color sometimes seen in an eclipsed moon.

We have all three of these things happening on Wednesday 31 January, and this is a combination we seldom get to see so have a look if you can.

Oh but can you? Below is a cartoon of when and where the viewing will be. For me, the setting moon is the time. Will I see it? Ha, my forecast is for clear and cold Wednesday morning, low temp will be somewhere around -11 C, so I would assume it will be perfect and near the horizon I might get some good color.

Image: PIRULITON (Own work) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons”

James Webb Telescope Timelapse

This video just puts me in a good mood, not sure why.

The description says: “this time-lapse shows activity in the NASA Johnson Space Center’s Chamber A cleanroom from the arrival of the Webb Telescope’s optical and instrument segment through to its roll out from the chamber after completing its cryogenic testing.”

We’re Going to Mars

We’re going to Mars, well in spirit anyway. If you signed up to have your name encoded on a chip that will be aboard the next Mars lander called InSight, you are now on-board.  I know I did and probably many of you did as well.

NASA – An engineer in the clean room at Lockheed Martin Space in Littleton, Colorado, affixes a dime-size chip onto the lander deck of NASA’s InSight spacecraft.

This second microchip, contains 1.6 million names submitted by the public to ride along with InSight to Mars. The chip was installed on Jan. 23, 2018. This joins another microchip that was previously installed that included 800,000 names for a grand total of 2.4 million names going to Mars as early as May 5, 2018.

Engineers at NASA’s Jet Propulsion Laboratory, Pasadena, California, put the names onto this tiny 0.3 square inches (8 millimeter-square) silicon wafer microchip using an electron beam to write extremely tiny letters with lines smaller than one one-thousandth the width of a human hair. The dime-size chip is affixed to the InSight lander deck and will remain on Mars forever.

Normally used to make high-precision nanometer-scale devices, this technique was also used to write millions of names that were transported on NASA Mars rovers and Orion’s first test flight.

InSight is the first Mars mission dedicated to study the deep interior of Mars. Its findings will advance understanding of the early history of all rocky planets, including Earth.

JPL, a division of Caltech in Pasadena, California, manages the InSight Project for NASA’s Science Mission Directorate, Washington. Lockheed Martin Space, Denver, built the spacecraft. InSight is part of NASA’s Discovery Program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama.

Credit: NASA/JPL-Caltech/Lockheed Martin

Comet Storm

If you were cruising along next to a comet and looked out your window you might see this scene. Reminds me of driving in a snowstorm except more random. This particular comet storm was outside of Rosetta during its journey with comet 67P/Churyumov–Gerasimenko.

ESA’s caption: Perhaps you live in a part of the world where you regularly experience snow storms or even dust storms. But for many of us, the weather forms a natural part of everyday conversation – more so when it is somewhat extreme, like a sudden blizzard that renders transport useless or makes you feel highly disoriented as you struggle to fix your sights on recognisable landmarks.

ESA’s Rosetta mission had a similar experience, for more than two years, as it flew alongside Comet 67P/Churyumov–Gerasimenko between 2014 and 2016. It endured the endless impacts of dust grains launched by gaseous outpourings as the comet’s surface ices were warmed by the heat of the Sun, evaporating into space and dragging the dust along.

This image was taken two years ago, on 21 January 2016, when Rosetta was flying 79 km from the comet. At this time Rosetta was moving closer following perihelion in the previous August, when the comet was nearer to the Sun and as such at its most active, meaning that Rosetta had to operate from a greater distance for safety.

As can be seen from the image, the comet environment was still extremely chaotic with dust even five months later. The streaks reveal the dust grains as they passed in front of Rosetta’s camera, captured in the 146 second exposure.

Excessive dust in Rosetta’s field of view presented a continual risk for navigation: the craft’s startrackers used a star pattern recognition function to know its orientation with respect to the Sun and Earth. On some occasions flying much closer to the comet, and therefore through denser regions of outflowing gas and dust, the startrackers locked on to dust grains instead of stars, creating pointing errors and in some cases putting the spacecraft in a temporary safe mode.

Despite its dangers, the dust was of high scientific interest: three of Rosetta’s instruments studied tens of thousands of grains between them, collectively analysing their composition, their mass, momentum and velocity, and profiling their 3D structure. Studying the smallest and the most pristine grains ejected is helping scientists to understand the building blocks of comets.

Two years before the image was taken, 20 January 2014, Rosetta was only just waking up from 31 months of deep-space hibernation. It arrived at its destination after 10 years in space  in August 2014, and released the lander Philae three months later. Rosetta made unique scientific observations of the comet until reaching its grand finale on 30 September 2016 by descending to the comet’s surface. By the end of the mission, more than a hundred thousand images had been taken by the high-resolution OSIRIS camera (including the one shown here) and the navigation camera, the majority of which are available to browse in the Archive Image Browser.

Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA