Meridiani Planum

The Mars Express is still going strong:

From ESA (Credit: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO):

This perspective view in Meridiani Planum was generated from the high-resolution stereo camera on ESA’s Mars Express.

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It shows the 19 km-wide Bopolu crater in the foreground along with its ejecta blanket – the debris thrown out from the surface during the impact event that formed the crater.

A trio of craters lie a short distance away in the background, the leftmost crater is Endeavour crater, where NASA’s Opportunity rover is currently exploring.

The Entry, Descent and Landing Demonstrator Module of ESA’s ExoMars 2016 mission will target a landing site on the smoother, left hand portion of this image in October 2016.

Insulation!

Ever notice how spacecraft destined to stay in orbit for some period of time always seem to have reflective foil around them? Ever wonder how that could possibly work?

You’re in luck!  ESA shows us the state-of-the-art in space insulation:

insulation

From ESA:
Blankets of multi-layer insulation (MLI) are used to cover satellite surfaces to help insulate them from orbital temperature extremes. These are the reason that satellites often look as though they’ve been covered in shiny Christmas wrapping.

MLI blankets are made up of multiple layers of very thin, metal-coated plastic film, with low-conducting ‘spacer’ material placed in-between such as silk, nylon or glass-fibre netting. Alternatively, MLI is sometimes deliberately crinkled to minimise any contact between layers.

In the airlessness of space, objects can be hot and cold at the same time, especially if one side is in sunshine and another is in shade. In such conditions, thermal radiation is the main driver of temperature change (rather than convection or conduction), and reflective MLI serves to minimise it.

Thermal control specialists aim to maintain the temperature of the satellite within set limits, to keep electronic and mechanical parts working optimally and to prevent any temperature-triggered structural distortion.

Placing MLI blankets on a satellite body is a skilled art in itself, with complex shapes needing to be created to fit around around edges or joints.

Credit: ESA–G. Porter

Perseids Shower

I wanted to make sure I posted a reminder about the Perseid meteor shower set to peak on the night of 11 to 12 August.  The could be a great shower!  Well yes, the Perseids are always good, I’m talking GREAT in terms of meteor rate which could approach 200 per hour!  Once seen, a shower like this will not be soon forgotten and it would be super to get the kids out.  It would make a great project for an organized outing, like for example a Boy Scout or Science Club camp out – brought up because organizing such an event is on my bucket list of things to do.  Anyway –

perseids2009

In 2009 there was a similar display and it was nothing short of spectacular.  A good portion of my viewing that night was spent in the back seat of a hatchback car riding home from a class.  It was an amazing show and I created two other avid meteor shower observers just by telling to “look up”.  The image shown here was from that very 2009 shower (Credits: NASA/JPL)

This year the moon could put a damper on things at least a little bit.  While the moon will be something like 62 percent illuminated it will be towards the south and on the way to setting by the time it is dark enough.

EARLY morning Friday is my plan.  Showers radiating from a very favorable direction (about north)  and the moon setting or set, I will be in my new patio recliner (dragged to the back lawn).  ERT or Expected Recliner Time should be about 03:30 local – sorry I couldn’t resist I am really pretty excited to try the new observing set up out. I’d like to think I might get a nice image like the one above and the potential is there, I’m not sure. The good thing is with “most things astronomy” the fun is in the trying.

Here are a few viewing tips from the NASA Meteoriod Environmental Office’s Rhiannon Blaauw:

Nearing The Solstice

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Saturn is nearing the northern-hemisphere solstice.  The shadow on the rings is shortening as the time gets closer in this image taken in May 2016 – compare to this image taken in 2007.

Notice the shadow is just beyond the Cassini Division, by the time the solstice gets here in May 2017 the shadow will be just past the half-way point of the B-ring (the wide light colored ring).  A year to wait for the solstice might seem like a long time, but consider it takes about 29.5 Earth-years for ONE Saturn year.  Visit our Saturn page for a lot more information on the planet and the moons.

Shadows on the Saturn system are not new.  Years before the Cassini spacecraft took these images, a gentleman named Robert Hooke noted shadows in drawings he made of Saturn in 1666.

Cassini took this image from about 3.2 million km / 2 million miles and there are a couple of things other than the shadow to take note of:  the northern polar vortex stands out nicely and the moon Mimas is visible to the lower left of the planet.

Image: NASA/JPL-Caltech/Space Science Institute

SDO Coming Back Online

On 02 August 2016 the SDO was witness to a lunar transit. The moon passed between the SDO and the Sun in a transit lasting nearly an hour from 11:13 UTC until 12:08 UTC (07:13 EDT to 8:08 EDT). When the transit over the SDO did not return to science mode.

sdotransit

Returning to science mode wasn’t quite as simple as I thought it would be. Two of the three instruments (the Helioseismic and Magnetic Imager, or HMI, and the Extreme Ultraviolet Variability Experiment, or EVE) were returning data two days later. The A1A instrument came back online and was returning data on 06 August.

Here’s a sample from A1A:
sdoa1a

A few more issues should be cleared up starting today according to Dean Pesnell over at the SDO blog: You Never Miss Them ‘TIl They’re Gone!

Images: SDO/NASA

This Week At NASA

An especially good episode this week. Very interesting bit on the atmosphere of the Jupiter moon Io, the sulfur dioxide atmosphere freezes onto the moons surface during the period where Jupiter shades the moon and then is restored as the shading goes away.

Video

A Long Dead Star

longdeadstar

The original caption:
This NASA/ESA Hubble Space Telescope image captures the remnants of a long-dead star. These rippling wisps of ionised gas, named DEM L316A, are located some 160 000 light-years away within one of the Milky Way’s closest galactic neighbours — the Large Magellanic Cloud (LMC).

The explosion that formed DEM L316A was an example of an especially energetic and bright variety of supernova, known as a Type Ia. Such supernova events are thought to occur when a white dwarf star steals more material than it can handle from a nearby companion, and becomes unbalanced. The result is a spectacular release of energy in the form of a bright, violent explosion, which ejects the star’s outer layers into the surrounding space at immense speeds. As this expelled gas travels through the interstellar material, it heats it up and ionise it, producing the faint glow that Hubble’s Wide Field Camera 3 has captured here.

The LMC orbits the Milky Way as a satellite galaxy and is the fourth largest in our group of galaxies, the Local Group. DEM L316A is not alone in the LMC; Hubble came across another one in 2010 with SNR 0509 (heic1018), and in 2013 it snapped SNR 0519 (potw1317a).

Copyright ESA/Hubble & NASA, Y. Chu