News From Space: MESSENGER and Mercury

messengerWith Curiosity’s ongoing research and manned missions being planned for Mars by 2030, it seems that the other planets of the Solar System are being sadly neglected these days. Thankfully, the MESSENGER spacecraft, which has been conducting flyby’s of Mercury since 2008 and orbiting it since 2011, is there to remind us of just how interesting and amazing the planet closest to our sun truly is.

And in recent weeks, there has been a conjunction of interesting news stories about Earth’s scorched and pockmarked cousin. The first came in March 22nd when it was revealed that of the many, many pictures taken by the satellite (over 150,000 and counting), some captured a different side of Mercury, one which isn’t so rugged and scorched.

Messenger_smooth1The pictures in question were of a natural depression located northeast of the Rachmaninoff basin, where the walls, floor and upper surfaces appear to be smooth and irregularly shaped. What’s more, the  velvety texture observed is the result of widespread layering of fine particles. Scientists at NASA deduced from this that, unlike many features on Mercury’s  ancient surface, this rimless depression wasn’t caused by an impact from above but rather explosively escaping lava from below.

In short, the depression was caused by an explosive volcanic event, which left a hole in the surface roughly 36 km (22 miles) across at its widest. It is surrounded by a smooth blanket of high-reflectance material, explosively ejected volcanic particles from a pyroclastic eruption, that spread over the surface like snow. And thanks to Mercury’s lack of atmosphere, the event was perfectly preserved.

Messenger_smooth2

Other similar vents have been found on Mercury before, like the heart-shaped depression observed in the Caloris basin (seen above). Here too, the smooth, bright surface material was a telltale sign of a volcanic outburst, as were the rimless, irregular shapes of the vents. However, this is the first time such a surface feature has been captured in such high-definition.

And then just three days later, on March 25th to be exact, Mercury began to experience its greatest elongation from the Sun for the year of 2013. In astronomy, this refers to the angle between the Sun and the planet, with Earth as the reference point. When a planet is at its greatest elongation, it is farthest from the Sun as viewed from Earth, so its view is also best at that point.

Mercury_31-03-13_0630What this means is that for the remainder of the month, Mercury will be in prime position to be observed in the night sky, for anyone living in the Northern Hemisphere that is. Given its position relative to the Sun and us, the best time to observe it would be during hours of dusk when the stars are still visible. And, in a twist which that may hold cosmic significance for some, people are advised to pay special attention during the morning of Easter Day, when the shining “star” will be most visible low in the dawn sky.

And then just three days ago, a very interesting announcement was made. It seems that with MESSENGERS ongoing surveys of the Hermian surface, nine new craters have been identified and are being given names. On March 26th, the International Astronomical Union (IAU) approved the proposed names, which were selected in honor of deceased writers, artists and musicians following the convention established by the IAU for naming features on the innermost world.

crater_names

The announcement came after MESSENGER put the finishing touches on mapping the surface of Mercury earlier this month. A good majority of these features were established at Mercury’s southern polar region, one of the last areas of the planet to be mapped by the satellite. And after a submission and review process, the IAU decided on the following names of the new craters:

Donelaitis, named after 18th century Lithuanian poet Kristijonas Donelaitis, author of The Seasons and other tales and fables.

Petofi, named after 19th century Hungarian poet Sandor Petofi, who wrote Nemzeti dal which inspired the Hungarian Revolution of 1848.

Roerich, named after early 20th century Russian philosopher and artist Nicholas Roerich, who created the Roerich Pact of 1935 which asserted the neutrality of scientific, cultural and educational institutions during time of war.

Hurley, named after the 20th century Australian photographer James Francis Hurley, who traveled to Antarctica and served with Australian forces in both World Wars.

Lovecraft, named after 20th century American author H.P. Lovecraft, a pioneer in horror, fantasy and science fiction.

Alver, named after 20th century Estonian author Betti Alver who wrote the 1927 novel Mistress in the Wind.

Flaiano, named after 20th century Italian novelist and screenwriter Ennio Flaiano who was a pioneer Italian cinema and contemporary of Federico Fellini.

Pahinui, named after mid-20th century Hawaiian musician Charles Phillip Kahahawai Pahinui, influential slack-key guitar player and part of the “Hawaiian Renaissance” of island culture in the 1970’s.

L’Engle, named after American author Madeleine L’Engle, who wrote the young adult novels An Acceptable Time, A Swiftly Tilting Planet & A Wind in the Door. L’Engle passed away in 2007.

Crater_names_August2012-580x376The campaign to name Mercury’s surface features has been ongoing since MESSENGER performed its first flyby in January of 2008. Some may recall that in August of last year, a similar process took place for the nine craters identified on Mercury’s North Pole. Of these, the names of similarly great literary, artistic and scientific contributors were selected, not the least of which was Mr. J RR Tolkien himself, author of Lord of the Rings and The Hobbit!

It’s no secret that the MESSENGER spacecraft has been a boon for scientists. Not only has it allowed for the complete mapping of the planet Mercury and provided an endless stream of high resolution photos for scientists to pour over, it has also contributed to a greater understanding of what our Solar System looked like when it was still in early formation.

Given all this, it is somewhat sad that MESSENGER is due to stand down at the end of the month, and that the next mission to Mercury won’t be until 2022 with the planned arrival of the joint ESA/JAXA BepiColombo mission. But of course, we can expect plenty of revelations and stories to emerge from all the scientific data collected on this latest trip. And I’m sure Mars will be more than willing to provide ample entertainment until 2022 comes to pass!

While we’re waiting, be sure to check out this informative video of MESSENGER’s contributions over the past few years:

Source: universetoday.com, (2), (3)

Mercury Mapped for the First Time

mercury_mapMercury is the smallest planet in the Solar System and has the closest proximity to our sun. As a result, it’s one of the most neglected when it comes to scientific study. While Mars, Venus, Jupiter and Saturn have been probed and photographed in exquisite detail during the space age, the closest planet to the Sun has had to make do with a few flybys from the Mariner 10 spacecraft in the early 1970s.

However, that is now changing thanks to NASA’s Messenger spacecraft. In addition to confirming the existence of ice and organic molecules back in November, the probe has also transmitted thousands of images of the planet over the past year. These have allowed NASA personnel to construct the first high-resolution maps of the planet, its own high-resolution maps, down to the scale of kilometers.

Global Map Of Mercury From Messenger.According to David Blewett, a scientist at the Applied Physics Laboratory at Johns Hopkins University and part of the Messenger team, part of the reason it has taken more than 30 years to revisit the planet since the Mariner 10 flybys was because a lack of public interest. Messenger, he claims, has changed all that. Speaking ahead of a briefing on Friday at the annual meeting of the American Association for the Advancement of Science in Boston, Blewett had this say:

“Messenger has revealed Mercury to be a fascinating, dynamic and complex world. We know now that it is an oddball planet. It’s the smallest of the eight planets but has the highest density. The interior structure is different than the other planets. The geologic surface is different to the moon and Mars. The surface composition is enigmatic because … it consists of rock types that we don’t have much experience with. It has a global, Earth-like magnetic field, Venus and Mars do not.”

messenger_mercuryThe new global map is an enhanced image that shows the different compositions of rocks on the surface of Mercury by color-coding them. The more orange areas are volcanic plains while the make-up of the rocks in the deep blue areas is unknown. Though Messenger was able to detect an abundance of individual elements on Mercury’s surface – including iron, titanium, sulphur and potassium – without rock samples to study, scientists cannot determine the exact compounds or minerals in which those elements are arranged.

But the biggest surprise came on the surface, where there was an abundance of relatively volatile elements such as potassium and sulphur was seen to be very high. Most of the models for the formation of Mercury predict that these elements should have evaporated away during the planet’s formation. So in addition to learning more about its surface features, scientists are now presented with the opportunity to study and learn more about the planet’s early history as well.

But of course, much of that information and research are going to have to wait for future generations of Rovers. These are likely to be similar in nature to Curiosity, in that they are remote controlled, networked robots with internal labs. But unlike those currently combing the Red Planet, these ones will have to be able to withstand surface temperatures in excess of 400 C and some dangerous surface activity. Hard to know exactly when NASA will be rolling any of those out, but the simplest answer is, not too bloody soon!

Check out the video of Mercury’s new color map as it rotates to show its fully-detailed surface. And FYI, this bit of breaking news has become my 900th post! Woohoo!

Source: gaurdian.co.uk

The Mercury/Mars Conjunction

mercury1This weekend, amateur astronomers and stargazers will be treated to a rare sight: the conjunction of Mercury and Mars in the sky. This has proven to be quite the confusing spectacle in the past, as people have often misinterpreted the conjunction of the two planets as the appearance of Mercury’s moon. Much like the appearance of other “pseudo-moons”, it is a mistake that litters the history of astronomy.

The conjunction will appear tonight, on February 8th, during the closest conjunction of two naked eye planets in 2013. This month offers a chance to see the fleeting Mercury in the sky, and the conjunction with Mars will provide the opportunity to see how Mercury would look in the night sky if it did indeed have a moon.

mercurymarsTo see the conjunction, be sure to find a site with a clear view of the western horizon, grab some binoculars, and begin watching the skies at about 15 minutes after local sunset. According to astronomers, this should coincide with February 8th at 17:00 Universal Time! Look for a reddish dot just above that bright star that hangs low in the sky, and you’ll have your two planets looking very much like they’re in orbit of each other.

But be quick about it, since you’ll only have a 15-30 minute window (depending on latitude) to snare the pairing before they follow the setting Sun below the horizon. Photographing the pair will be tricky, though not impossible, since they present a very low contrast against the bright background twilight sky. And just in case you’re not impressed with the sight itself, consider that with Curiosity and other rovers operating on Mars and the Messenger satellite orbiting Mercury, permanent robotic “eyes” are monitoring both!

Good luck and good gazing! And if you happen to snap a picture of the conjunction, don’t hesitate to send it my way. I’ll be sure to post it with the deets of the amateur professional who made it happen!

Source: universetoday.com

Ice and Organics Found on Another Planet!

mercury_messengerYes, the announcement from the Curiosity team yesterday that no organics have been found on Mars (yet) certainly came as a big disappointment. However, people may be interested to hear that organic molecules were discovered on a different planet in our Solar System, along with water and ice. Would you believe it, the planet is Mercury? Yes, the world famous for lakes of molten metal and extreme heat may actually boast the building blocks of life.

This information is the latest to come from NASA’s MESSENGER spacecraft, which is now orbiting the closest planet to our Sun. It confirms what was postulated 20 years ago, after images were taken of the polar region and detected radar-bright materials which were beleived to be water and ice. And where water and ice occur, organic molecules are often sure to follow. Though Mercury boasts the hottest environment of any planet in the Solar System, the area in question lies within a permanent shadowed series of craters on the northern pole.

Scientists today said that Mercury could hold between 100 billion to 1 trillion tons of water ice at both poles, and the ice could be up to 20 meters deep in places. Additionally, intriguing dark material which covers the ice could hold other volatiles such as organics. Unfortunately, all of this water comes in the form of ice, as surface temperatures in the poles are too cold to allow for a thaw. In addition, the total lack of atmosphere on Mercury would mean that any liquid would evaporate and be sucked into space very quickly.

At a briefing which was held yesterday, Sean Solomon – MESSENGER Principal Investigator – has this to say about the news: “These findings reveal a very important chapter of the story of how water ice has been delivered to the inner planets by comets and water rich asteroids over time.” In short, it is believed that these ice deposits and organic molecules were delivered to the planet through a series of meteor impacts, and which have survived thanks to the existence of Mercury’s permanently shadowed polar regions.

Granted, no settlers are ever likely to be making a home on Mercury – not without some serious technological innovations! – but the discovery is a very interesting find and does help scientists to understand how life may have begun here on Earth. What’s more, this news may help Curiosity and other science teams to determine where and how organic molecules and ice could be found on Mars. The challenges there are similar to those on Mars, since she too is an inner planet that has virtually no atmosphere and a great deal of surface radiation, not to mention that she too would have been the recipient of water ice and organics through meteoric impacts.

So c’mon Mars! Show us what you got. You don’t want to be outdone by your Hermian cousin do ya?