All posts by Tom

Larsen C

I’ve seen a few different views of Larsen C and this image from ESA’s Sentinel-1 spacecraft is one of the best and arguably the most interesting.

ESA — On 12 July 2017, Europe’s Copernicus Sentinel-1 mission returned radar images showing that a lump of ice more than twice the size of Luxembourg had broken off the Antarctic Peninsula. Since then, this large tabular iceberg – known as A68 – has drifted about 5 km from the ice shelf. Images from Sentinel-1 also show that a cluster of more than 11 smaller icebergs has also now formed, the largest of which is over 13 km long. These ‘bergy bits’ have broken off both the giant iceberg and the remaining ice shelf. The image has been compiled using Sentinel-1 acquisitions on 27 July (right) and 30 July (left).

Image contains modified Copernicus Sentinel data (2017), processed by BAS–A. Fleming.

The Blue Streak Rocket

The Blue Streak developed by Britain started out as a military weapon in 1955. The military aspect of the programme was ended in 1960 and was reassigned to the European Launcher Development Organisation (ELDO) to launch satellites into orbit.

Britain pulled out of the ELDO in 1971, the last (British) Blue Streak programme launch was on 12 Jaunuary 1970 and the last ELDO Blue Streak launch being from French Guyana in 1971.

The entire ELDO project was canceled in 1973 and was replaced the the European Space Agency (ESA) we know today.

SPECTACULAR!

A breath taking image and great work from citizen scientists Gerald Eichstädt and Seán Doran using data from  the Juno spacecraft and publicly available at JunoCam. Fantastic job!!!!  Be sure to click the image for  the larger version.

NASA’s caption: A dynamic storm at the southern edge of Jupiter’s northern polar region dominates this Jovian cloudscape, courtesy of NASA’s Juno spacecraft.

This storm is a long-lived anticyclonic oval named North North Temperate Little Red Spot 1 (NN-LRS-1); it has been tracked at least since 1993, and may be older still. An anticyclone is a weather phenomenon where winds around the storm flow in the direction opposite to that of the flow around a region of low pressure. It is the third largest anticyclonic oval on the planet, typically around 3,700 miles (6,000 kilometers) long. The color varies between red and off-white (as it is now), but this JunoCam image shows that it still has a pale reddish core within the radius of maximum wind speeds.

Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager. The image has been rotated so that the top of the image is actually the equatorial regions while the bottom of the image is of the northern polar regions of the planet.

The image was taken on July 10, 2017 at 6:42 p.m. PDT (9:42 p.m. EDT), as the Juno spacecraft performed its seventh close flyby of Jupiter. At the time the image was taken, the spacecraft was about 7,111 miles (11,444 kilometers) from the tops of the clouds of the planet at a latitude of 44.5 degrees.

Plasma Sheet

The Sun is pretty energetic at the end of the solar cycle. This sheet of plasma above occurred on 28 July in about the same area that sunspot AR2665 is now. That sunspot, by the way, is the same one was associated with a very powerful CME on the far side of the Sun about a week ago.

There is a short video of the plasma sheet available from NASA.

NASA – A sheet of plasma blasted out into space from just behind the edge of the sun (July 28, 2017). While some material escaped into space, a portion of it was unable to break the pull of gravity and the magnetic forces nearby and can be seen falling back to the sun. The 3.5 hours of action was captured in a wavelength of extreme ultraviolet light.

Image: NASA/GSFC/Solar Dynamics Observatory

To Scale: The Solar System

A great video by Wylie Overstreet and Alex Gorosh.

I even do this every now and then myself just for fun and I get a bit of exercise in the process. I don’t do it quite the way Wylie and Alex did  as I just pace off this distances but even so, it is very interesting.

This is a GREAT activity for children!  Depending on what scale you use for distance you all you will need is a flat piece of ground, like say a football pitch. Even at one step per 10 million kilometers you can get a pretty long ways away from the starting point so plenty of room is helpful.

You can change the scale to fit your needs as long as you are looking at distance and not necessarily planetary sizes; also a good exercise for youngsters to exercise their brains during the school holiday.

To get you started have a look at this page from the Lunar and Planetary Institute.

ESA’s JUICE

This ‘family portrait’ shows a composite of images of Jupiter, including it’s Great Red Spot, and its four largest moons. From top to bottom, the moons are Io, Europa, Ganymede and Callisto. Europa is almost the same size as Earth’s moon, while Ganymede, the largest moon in the Solar System, is larger than planet Mercury.
While Io is a volcanically active world, Europa, Ganymede and Callisto are icy, and may have oceans of liquid water under their crusts. Europa in particular may even harbour a habitable environment.
Jupiter and its large icy moons will provide a key focus for ESA’s JUICE mission. The spacecraft will tour the Jovian system for about three-and-a-half years, including flybys of the moons. It will also enter orbit around Ganymede, the first time any moon beyond our own has been orbited by a spacecraft.
The images of Jupiter, Io, Europa and Ganymede were taken by NASA’s Galileo probe in 1996, while the Callisto image is from the 1979 flyby of Voyager.

The JUICE mission sounds like a typical ESA mission — ambitious and well planned.  It should be exciting, even if there is a long tome until launch.  Read more about the JUICE mission here.

Curiosity Climbing Mt Sharp

As seen from orbit (look at the center of the image). Click for a larger view.

NASA – the feature that appears bright blue at the center of this scene is NASA’s Curiosity Mars rover on the northwestern flank of Mount Sharp, viewed by NASA’s Mars Reconnaissance Orbiter.  Curiosity is approximately 10 feet long and 9 feet wide (3.0 meters by 2.8 meters).

The view is a cutout from observation ESP_050897_1750 taken by the High Resolution Imaging Science Experiment (HiRISE) camera on the orbiter on June 5, 2017.  HiRISE has been imaging Curiosity about every three months, to monitor the surrounding features for changes such as dune migration or erosion.

When the image was taken, Curiosity was partway between its investigation of active sand dunes lower on Mount Sharp, and “Vera Rubin Ridge,” a destination uphill where the rover team intends to examine outcrops where hematite has been identified from Mars orbit.  The rover’s surroundings include tan rocks and patches of dark sand. The rover’s location that day is shown at https://mars.nasa.gov/multimedia/images/2017/curiositys-traverse-map-through-sol-1717 as the point labeled 1717. Images taken by Curiosity’s Mast Camera (Mastcam) at that location are at https://mars.nasa.gov/msl/multimedia/raw/?s=1717&camera=MAST%5F.

As in previous HiRISE color images of Curiosity since the rover was at its landing site, the rover appears bluer than it really is. HiRISE color observations are recorded in a red band, a blue-green band and an infrared band, and displayed in red, green and blue.  This helps make differences in Mars surface materials apparent, but does not show natural color as seen by the human eye.

Lower Mount Sharp was chosen as a destination for the Curiosity mission because the layers of the mountain offer exposures of rocks that record environmental conditions from different times in the early history of the Red Planet. Curiosity has found evidence for ancient wet environments that offered conditions favorable for microbial life, if Mars has ever hosted life.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA’s Science Mission Directorate, Washington.

Image Credit: NASA/JPL-Caltech/Univ. of Arizona

Doomed Comets

Comets coming close to (but not actually impacting) the Earth are very cool. Comets getting too close to the sun are doomed and we get to see them thanks to our space based observatories.