All posts by Tom

Magnetic Field Lines

I would like to see more of this. Actually I’d also like to see this done from a more distant perspective. Good work though.

The dark areas by the way are a source of solar winds which are probably not not cause earthquakes here on Earth; we start hearing that because the “other” cause (which also cannot be correlated) are sunspots and solar flares. I guess when you don’t get one you can fall back on the other.

One other thing we can see is the absence of high latitude sunspots which would be the hallmark of a new solar cycle. So are we in a “Grand Solar Minimum? Maybe, come back in ten years or so and if we are still stuck at solar minimum levels we could possibly say yes. It’s WAY too early to make such claims at this point. So when you hear that on the internet be sure to take it with a box of salt.

NASA’s caption: NASA’s Solar Dynamics Observatory (SDO) scientists used their computer models to generate a view of the Sun’s magnetic field on August 10, 2018. The bright active region right at the central area of the Sun clearly shows a concentration of field lines, as well as the small active region at the Sun’s right edge, but to a lesser extent. Magnetism drives the dynamic activity near the Sun’s surface.

SDO is managed by NASA’s Goddard Space Flight Center, Greenbelt, Maryland, for NASA’s Science Mission Directorate, Washington. Its Atmosphere Imaging Assembly was built by the Lockheed Martin Solar Astrophysics Laboratory (LMSAL), Palo Alto, California.

Image Credit: NASA/GSFC/Solar Dynamics Observatory

Proba’s Solar Eclipses

ESA: Thanks to a quirk of our cosmos, the Moon’s average distance from Earth is just right for it to appear as the same size in the sky as the significantly larger Sun. Once in a while the Moon slides directly between Earth and the Sun such that it appears to cover our star completely, temporarily blocking out its light and creating a total solar eclipse for those along the narrow path cast by the Moon’s shadow.

But sometimes the alignment is such that the Moon only partially covers the Sun’s disc. Such a partial eclipse occurred on Saturday for observers located primarily in northern and eastern Europe, northern parts of North America, and some northern locations in Asia.

ESA’s Sun-watching Proba-2 satellite orbits Earth about 14.5 times per day and with its constant change in viewing angle, it dipped in and out of the Moon’s shadow twice during Saturday’s eclipse.

Selected views of the two partial eclipses are seen side-by-side here – the first (left) was captured at 08:40:12 GMT and the second (right) at 10:32:17 GMT on 11 August.

The images were taken by the satellite’s SWAP camera, which works at extreme ultraviolet wavelengths to capture the Sun’s hot turbulent atmosphere – the corona – at temperatures of about a million degrees, which can be seen in the background.

Watch the full image sequence here.

Image: ESA/Royal Observatory of Belgium

From The Travels of Cassini

Here’s sort of a throwback, one of Cassini’s great images newly processed.  The release title is “Translucent Arcs” and that is very descriptive. To me the image show the ring structure in terms of thickness density. Combined with the Sun-Saturn-Cassini angular configuration the rings seem to provide almost a “screen-door” effect to the scene.

This view is much different than what was published in 1622 by Fortunio Liceti in De Novis Astris et Cometis and much different than the sight from a backyard telescope.

Saturn is nothing short of breathtaking, if you’ve never seen it put it on your “bucket list” and look for suitable viewing opportunities — you might be surprised, local colleges and universities sometimes have public viewing and don’t overlook local astronomy clubs.

Here’s the caption from NASA:  Saturn’s rings are perhaps the most recognized feature of any world in our solar system. Cassini spent more than a decade examining them more closely than any spacecraft before it.

The rings are made mostly of particles of water ice that range in size from smaller than a grain of sand to as large as mountains. The ring system extends up to 175,000 miles (282,000 kilometers) from the planet, but for all their immense width, the rings are razor-thin, about 30 feet (10 meters) thick in most places.

From the right angle you can see straight through the rings, as in this natural-color view that looks from south to north. Cassini obtained the images that comprise this mosaic on April 25, 2007, at a distance of approximately 450,000 miles (725,000 kilometers) from Saturn.

The Cassini spacecraft ended its mission on Sept. 15, 2017.

Image: NASA/JPL-Caltech/Space Science Institute

The Origin of the Perseids

Ever wonder where the Perseids come from? Wonder no more because this is Comet Swift-Tuttle and it is the origin of the Perseids showers.

I have been stymied in my viewing thanks to persistent clouds. In the few breaks I have managed to see a few meteors. Yesterday morning mostly, trying to watch the meteors and the launch of the Parker Space Probe (from the outside and through a window) at the same time.

Here’s ESA’s caption for the image above (E.E. Barnard/Internet Archive ):Comet Swift–Tuttle, formally 109P/Swift–Tuttle, is an enormous, icy comet on a 133 year orbit around the Sun, and the reason for the spectacular annual Perseids meteor showers on Earth.

This image shows the comet photographed on 4 April 1892 (top) and 6 April 1892 (bottom) by Professor EE Barnard, taken from Plate III in A Popular History of Astronomy in the nineteenth century by Agnes M Clerke (third edition), courtesy of Internet Archive.

Once a year, Earth passes through a section of Swift–Tuttle’s cometary tail — a cloud of particles ejected from the comet, most of which have been in this formation for a thousand years. As these tiny particles enter Earth’s atmosphere at extremely fast speeds, they burn up, resulting in the wonderful show that is a meteor shower.

Every year from the middle of July to late August, observers are treated to the spectacle of glowing cosmic debris, streaming across the night’s skies. This year the shower will peak from the evening of Sunday 12 August to the early hours of Monday 13 August. The Moon will be a new crescent moon, fortunately setting before the show really gets underway and so leaving the skies dark for what is set to be the best shower of 2018.

Discovered in 1862, the ‘near-Earth comet’ Swift–Tuttle has a nucleus 26 km in diameter — that’s two-and-a-half times the size of the asteroid that wiped out the dinosaurs, and it is travelling four times as fast.

As the largest Solar System object (bar the Moon) to repeatedly pass close to Earth, comet Swift-Tuttle’s movements have been meticulously studied by scientists around the globe. It’s most recent ‘perihelion’ — the point in its orbit in which it comes closest to the Sun — was in 1992, and the next won’t be until 12 July 2126.

Fortunately all of comet Swift–Tuttle’s orbits for the next 2000 years have been intricately calculated, when Earth is 100% safe – passing for example 22.9 million km from Earth in 2126 and 22 million km in 2261.

A close encounter is expected around 15 September 4479, when Swift-Tuttle is expected to pass within 1.6 million km of Earth — more than 90 times closer than the Sun, or, only about four times the distance of the Moon.

So, for the foreseeable future we will continue to enjoy the beautiful show put on every year by the remnants of this Sun-grazer’s historic journeys to the centre of our Solar System. These stunning events also serve as a reminder that our planet has been visited before by huge cosmic space-rocks, and has the potential to be once again.

Parker Solar Probe Launch – Replay

Here we go! It’s always scary watching the take off because of the fire envelops the outside prior to lift off.

After two minutes in, the rocket is still consuming 5,000 pounds of fuel per second that’s 2,268 kg/sec!

YES! Fairing deploy!

My Perseid watching this morning was greatly hindered by transient clouds.

Parker Solar Probe Launch – Scrubbed

Earlier . . .
So here it is a hour after the initial launch time and the count is under way again.

New T-Zero time is 08:28 UT /04:28 ET – Sunday 12 August 2018.

Nix that, there is a hold at T minus 1:55

Clock is re-set to T-4

Is this scrubbed? Not much window time left.

Yes, SCRUBBED. The next try will be tomorrow (same time). I’ll leave the feed up for a time.

You could hear the disappointment in the voices of the launch team. This is an important mission so everything needs to be spot on.

I will update with a reason for the delay, they said but I missed it – noisy here this morning.

Gaseous Helium alarm has been indicated. The launch might NOT happen tomorrow depending on what is actually going on. Stay tuned.

By the way, if you are interested in hearing the Kennedy communications, you can usually hear them during launches at Broadcastify.com

The Perseids are Here!

My best recollection of the Pereids came from one night years ago now. I was in the back seat of my car, looking upwards through the hatchback window. No, not like that! I was the backseat passenger of a car load of students learning how to initiate intravenous therapy, actually the first class where the class was starting IV’s on each other. Anyway the 45-minute journey was an incredible Perseid viewing experience – as was the EMT class.

Ok, I digress. GO OUTSIDE AND LOOK TO THE NORTH! Not just now but tomorrow too!

Ready or Not, Here We Come

Tomorrow we will see the start of a historic mission, the Parker Solar Probe.

Launch time: 07:33 UTC / 03:33 EDT from Cape Canaveral in Florida, USA.

Spaceport: Cape Canaveral, Florida

Launching rocket: United Launch Alliance Delta IV Heavy

There will be a live link about a half hour before launch (07:00 UTC / 03:00 EDT). If you miss it come back a bit later as the live feed will be replaced with replays).

Also, so far there are no issues working that would delay launch but that possibility ALWAYS exists.

The image above is from the Solar Dynamics Laboratory taken yesterday (NASA/SDO). The Sun has been very quiet in terms of sunspots.

It’s Difficult to Get to Sun

Getting to the Sun or Mercury for that matter is not as easy as one might think. I looked around for an old explanation I wrote some years ago and then NASA put out this short video that fill the bill quite nicely.

In this case it is the Parker Solar Probe taking flight Saturday morning and much the same idea goes for the upcoming BepiColumbo mission to Mercury.