Watch as a newly-discovered comet plunges into the Sun

Saturday, March 4, 2017, 1:36 PM - A newfound comet is spotted on its fiery plunge into the Sun, a Mars rover shows us that dust moving around is more fascinating than we might think, and Hubble snaps a beautiful image of a distant galaxy. It's Science Pics of the Week!

A dirty snowball makes a fiery plunge

As the NASA/ESA satellite SOHO - the Solar and Heliospheric Observatory - keeps a 24/7 watch on the Sun, it sees some pretty interesting stuff: flares, eruptions of solar matter, stars and planets that wander through its view, and what's particularly relevant at the moment - a peculiar class of comets that dive to their fiery "deaths", one after the other.

The latest of these comets - known as "sungrazers" - slipped into the view of SOHO's LASCO coronagraph on the morning of March 2, 2017. Follow the comet's progress below, as SOHO imaged it five times every hour:

This animation shows SOHO's LASCO 3 and LASCO 2 coronagraph views, from 1830 UTC March 2 to 0200 UTC March 4, chronicling the brightening of a newly discovered sungrazer comet (tracking from bottom left towards centre) and its inevitable demise in the fiery heat from the Sun. Credit: SOHO/NASA/ESA. Animation and notations by S. Sutherland

"SPOILER ALERT," astrophysicist Karl Battams, who runs the NASA-funded Sungrazer Comet program at the U.S. Naval Research Laboratory, posted to Twitter on Friday. "This comet will NOT survive! (It'll vaporize loooong before it even nears the solar surface)."

Battams, who has run the Sungrazer Comet program since 2003, has watched many of these comets vanish in the heat of the Sun, and SOHO's cameras have catalogued over 3,100 of them since the satellite launched in 1995.

The LASCO coronagraph is an instrument the satellite uses to observe the Sun's corona, to keep track of the solar wind, coronal streamers and coronal mass ejections. It does this by blocking out all direct light from the Sun, using a small disk that is held out in front of the camera by a thin arm (both disk and arm are visible in the image, above). With the disk perfectly positioned to cover up the Sun, the sensitive instrument can see all of the activity going on around the Sun. LASCO 3 provides a wide field of view, while LASCO 2 zooms in for a closer look.

Curiosity sees the Martian winds blow

Mars' atmosphere is extremely thin compared to Earth's, with a surface pressure that's less than 1 per cent of what we experience here. So, when Martian winds blow, it's difficult for them to muster more than just a light breeze.

That seems to be enough, though, to move around the Martian dust and sand, as these latest images from NASA's Curiosity rover reveal.

Credit: NASA/JPL-Caltech/MSSS

According to NASA:

This pair of images shows effects of one Martian day of wind blowing sand underneath NASA's Curiosity Mars rover on a non-driving day for the rover. Each image was taken just after sundown by the rover's downward-looking Mars Descent Imager (MARDI). The area of ground shown in the images spans about 3 feet (about 1 meter) left-to-right.
The first image was taken on Jan. 23, 2017, during the 1,587th Martian day, or sol, of Curiosity's work on Mars. Figure A is this image with a scale bar in centimeters. The second was taken on Jan. 24, 2017 (Sol 1588).  The day-apart images by MARDI were taken as a part of investigation of wind's effects during Martian summer, the windiest time of year in Gale Crater.

That's not all.

Normally, Curiosity seems to go about its picture-taking at a fairly leisurely pace, but on February 12, 2017, the rover's navigational cameras (NavCams) were set to snap images five times a minute, in an attempt to capture dust devils!

NavCam images from Feb 12, 2017 (Curiosity's so 1,607). The black outline separates static reference images (outside) from animation images (inside) that were sampled every 12 seconds. Credit: NASA/JPL-Caltech/TAMU

As shown above, the rover was quite successful in its attempt.

According to NASA:

Within a broader context view, the rectangular area outlined in black was imaged multiple times over a span of several minutes to check for dust devils. Images from the period with most activity are shown in the inset area. The images are in pairs that were taken about 12 seconds apart, with an interval of about 90 seconds between pairs. Timing is accelerated and not fully proportional in this animation.
One dust devil appears at the right edge of the inset -- toward the south from the rover -- in the first few frames. Another appears on the left -- toward south-southeast -- later in the sequence. Contrast has been modified to make frame-to-frame changes easier to see. A black frame is added between repeats of the sequence.

Even after more than 1,600 days roving around on the Martian surface (nearly 4.5 Earth years or around 2.5 Mars years), Curiosity is still sending back amazing results!

Hubble reveals a beautiful hybrid galaxy

Staring far out into space, some 400 million light years away, the Hubble Space Telescope recently returned this image to Earth:

Click or tap image to enlarge (Seriously! Please do it! Wow!) Credit: ESA/Hubble & NASA

This is galaxy UGC 12591, which is a rather unassuming name for something so absolutely stunning.

Rather than conforming to just one type of galaxy - elliptical, spiral or lenticular - UGC 12591 refuses to be locked down, and is classified as a hybrid of spiral and lenticular.

According to the Hubble Space Telescope website:

The galaxy itself is also extraordinary: it is incredibly massive. The galaxy and its halo together contain several hundred billion times the mass of the Sun; four times the mass of the Milky Way. It also whirls round extremely quickly, rotating at speeds of up to 1.8 million kilometres per hour!

While this huge galaxy is undoubtedly remarkable and beautiful to look at, it is also serving a scientific purpose for us. By observing the structure of UGC 12591 and watching it spin, astronomers can determine how it formed. Did it somehow evolve this way on its own, accumulating enormous amounts matter early in its formation, to grow to such large proportions over time, or did it reach its current state by gobbling up smaller galaxies around it?

Answering these questions will help us to better understand the formation, and eventual fate, of our own galaxy.

Sources: ESA/NASA | Karl Battams | NASA | SpaceTelescope.org

BONUS FEATURE: NOAA's GOES-16 weather satellite continues to send back amazing images as it's testing continues in geosynchronous orbit. Check out this incredible transition from day to night mode!