Monday, November 5, 2018

NASA's Kepler Space Telescope Runs Out of Fuel


  NASA officials announced on October 30 that the Kepler space telescope has run out of fuel and will be decommissioned in the coming weeks. This marks a lasting legacy that is responsible for 70 percent of the roughly 3,800 confirmed exoplanets discoveries to date.
  Unlike NASA's Cassini spacecraft which was deorbited into Saturn's thick atmosphere in September 2017, Kepler will receive a much simpler end. Team members will beam a single, simple command to the spacecraft, triggering a decommissioning sequence. This will shut down its radio transmitter and onboard fault-protection systems, converting the telescope into an inert chunk of floating metal.
   "Kepler is currently trailing the Earth by about 94 million miles, and will remain the same distance from the Earth for the foreseeable future," Charlie Sobeck, project system engineer at NASA's Ames Research Center in Moffett Field, California, said during a teleconference with reporters.
  Kepler was launched back in March 2009, with its mission to determine the frequency of Earth-like plants around the Milky Way galaxy. Its first mission was initially composed of observing close to 150,000 stars simultaneously. Eventually this mission ended in May 2013 when the spacecraft lost the second its four orientation-maintainng reaction wheels. However after some remote modifications, a new mission was launched in 2014 as K2. that hauled in an additional 34 exoplanet finds.

New Hope for Cystic Fibrosis Could Save Over 90%, Doctors Say



[TO BREATHE EASIER Patient with approved treatment for Cystic Fibrosis]

For several years now, scientists have continuously struggled to find a therapeutic treatment suitable to aiding most victims of cystic fibrosis. Now, with a newfounded triple-drug approach, although still being tested, scientists are one step closer to a revolutionary uncovery.

Cystic fibrosis, a mutation in a gene also known as CFTR, forces the body to either produce defective versions of a protein, or none at all. With the hereditary disorder affecting the exocrine glands, an abnormally thick mucus is generated, and thus the pancreatic ducts as well as intestines are blocked.

So how can this be treated?

Well, as of recent laboratory studies conducted, two triple-drug approaches, both of which underwent processes of four week periods, showed a breakthrough with the improvement in lung function of people with the most common cystic fibrosis-causing mutation. About 90% of people with the disease have this mutation, and so with continued testing, this particular non-invasive triple-drug combination could potentially provide an effective treatment for the vast majority of cystic fibrosis patients.

This new triple-drug treatment builds upon the success of an earlier drug, that of which had been approved in 2012 for patients who had a much less common mutation. This particular treatment achieved high rates of success, as proven with detailed data analysis. Steven Rowe, a pulmonologist at the University of Alabama states, “They are in the hospital much less,” he says, and “the way they feel on a day-to-day basis is substantially improved.”

Thus, with the oncoming development of the triple-drug treatment, scientists are predicting a breakthrough in cystic fibrosis treatments, with some believing that, once approved, it will be life-changing for over 90% of patients living with cystic fibrosis.

 
Credit:
Cunningham, Aimee. “New Therapies Pack a Triple-Drug Punch to Treat Cystic Fibrosis.” Science News, Science News Organization, 19 Oct. 2018, www.sciencenews.org/article/new-therapies-pack-triple-drug-punch-treat-cystic-fibrosis?tgt=nr.
Image Credit:
News, CKOM. “Mom Reacts as Coverage Denied for $240K Cystic Fibrosis Drug.” 650 CKOM, www.ckom.com/2018/10/18/422789/

Monday, October 29, 2018

NASA Spots Rectangular Iceberg in Antarctica


During Operation IceBridge, NASA's longest-running aerial survey of polar ice, photos of a very sharp-angled, tabular iceberg were captured over the northern Antarctic Peninsula on October 16, 2018. This iceberg was found by senior support scientist Jeremy Harbeck just off of the Larsen C Ice Shelf.
NASA scientists explained later that the process that formed this iceberg is actually fairly common. Tabular icebergs are wide and flat, like sheet cake. They split from the edges of ice shelves through a process that is relatable like a fingernail growing too long and cracking off at the end. This often makes them rectangular and geometric as a result.

A second iceberg spotted by Jeremy Harbeck. Image Credit: NASA/Harbeck
“I thought it was pretty interesting; I often see icebergs with relatively straight edges, but I've not really seen one before with two corners at such right angles like this one had,” Harbeck said. “I was actually more interested in capturing the A68 iceberg that we were about to fly over, but I thought this rectangular iceberg was visually interesting and fairly photogenic, so on a lark, I just took a couple photos."
Read more about this fascinating story at:

Image Credit: NASA/Jeremy Harbeck

Sunday, October 28, 2018

“Mini-Eyes” Show Scientists How Colour Vision Develops


Our world appears in vivid colours, thanks to the cone photoreceptors in our eyes, yet little was known about how they developed until researchers observed it by growing tiny blobs of eye tissue in a lab.


   Scientists at the Johns Hopkins University (JHU) have successfully grown organoids (miniature organs) that contained photoreceptors who responded to light and behaved like human cone cells. Intriguingly, these three colour-sensing cells appeared in the same order as they do naturally in a fetus: first the blue-light-sensing cone cells and then the ones who sense green light or red light.
   Though it’s already known that the blue cone cells develop first, it was unclear as to why. “We weren't sure what in a development context cued those cells to be different from each other,” said lead study author Kiara Eldred, a doctoral candidate in the Department of Biology at JHU. 




A retinal organoid — at days 43 of growth — doesn’t really look (get it?) like an eye but is allowing scientists to see (so sorry) how eye cells grow and interact.

Credit: Johns Hopkins University

 
   However, using prior research, the scientists hypothesized that the thyroid hormone helped trigger the development of cells linked to colour vision. To test this, they manipulated the cone cells' receptors for the hormone, and the results didn’t disappoint. The researchers reported that when the receptors for the hormone were disabled, the mini-eyes grew only blue-light-sensing cells. They also found that when the organoids were saturated with the hormone early in the growth process, all the colour cells developed into red or green light-sensing cells.
    “That told us that we understood the mechanism enough that we could grow human retinal cells in a dish, and we could tell them what kind of cells we wanted to make,” said study co-author Robert Johnston Jr., an assistant professor in the JHU Department of Biology, 
   Experimenting with these “mini-eye” cells provided our first glimpse at what produces our colour vision, and the benefits won’t stop there. Studying lab-grown eye tissue will be valuable for uncovering other aspects of our unique sight, as well as provide treatment insights for blindness and vision-related illnesses.




Towering 'Penitente' Spikes May Exist on the Surface of Europa

   According to new research from scientists at the NASA Ames Research Centre, spikes of ice known as penitentes may tower above the surface of Jupiter's moon Europa. Famous in the media in recent years for its suspected subsurface saltwater ocean, this is a prime location in the solar system for the search for extraterrestrial life.
   In the paper, scientists looked at the sublimation rates of water ice across Europa's surface. By factoring other events that might erode the icy moon's surface, such as asteroid impacts or electrically charged particles hitting the moon from Jupiter, it was found that this model would create a rough surface on Europa. In the equatorial area of the moon, they found that sublimation would be dominant enough to sculpt penitentes up to about 15 metres high and 7 metres across over a span of 50 million years (about the age of Europea's surface)
   These hypothesized areas of jagged ice towers might pose a hazard for any future missions to Europa including NASA's Europa lander concept. This will make reconnaissance key prior to deployal of any probes from orbit.
   However it is just as possible that the penitente model may not apply to Europa. As it was based on penitente formation on Earth, some factors including a lack of atmosphere and Earth ices containing salts and sulfurous compounds could play a role in affecting this model.
   "It is always pleasant to see how rigorous science can help us imagine how the surface of an unknown planet could be at a scale never observed yet," said planetary scientist Cyril Grima at the University of Texas at Austin, who did not take part in this research.
Read more about this fascinating story at:  https://www.popsci.com/ice-spikes-europa

Image: Penitentes in the Atacama desert via ESO/B. Tafreshi

Thursday, October 25, 2018

Astronomers Discover Slowest Ever Pulsar Star

   A team of astronomers including a PhD student from the University of Manchester has discovered the slowest-spinning pulsar star to date. This study was made possible through observations using the Low-Frequency Array (LOFAR) in the Netherlands.
   The product of a supernova, pulsars are rapidly rotating neutron stars that produce electromagnetic radiation at specific frequencies. Located in the constellation Cassiopeia approximately 5,200 light-years away from Earth, this pulsar spins at a rate of once every 23.5 seconds. This contrasts with the previously slowest pulsar which had emitted radio waves every 8.5 seconds.
   Unlike previous discoveries, this pulsar also releases radio emissions that last only 200 milliseconds per rotation. That meant that if the timing had been off even a few milliseconds, the radio beams might have missed Earth entirely making this discovery impossible.
   “The radio emission that comes from a pulsar acts like a cosmic lighthouse and you can only see the signal if the radio beam is facing towards you," said Chia Min Tan from Manchester's School of Physics and Astronomy. "In this case the beam is so narrow that it might easily have missed the Earth.   “Slow-spinning pulsars are even harder to detect. It is incredible to think that this pulsar spins more than 15000 times more slowly than the fastest spinning pulsar known. We hope that there are more to be found with LOFAR”.

Image Credit: Danielle Futselaar and ASTRON

Friday, October 19, 2018

NASA wants to send humans to Venus – the brilliant idea laid out




Popular science fiction of the early 20th century depicted Venus as some kind of wonderland of pleasantly warm temperatures, forests, swamps and even dinosaurs. In 1950, the Hayden Planetarium at the American Natural History Museum were soliciting reservations for the first space tourism mission, well before the modern era of Blue Origins, SpaceX and Virgin Galactic. All you had to do was supply your address and tick the box for your preferred destination, which included Venus.
Today, Venus is unlikely to be a dream destination for aspiring space tourists. As revealed by numerous missions in the last few decades, rather than being a paradise, the planet is a hellish world of infernal temperatures, a corrosive toxic atmosphere and crushing pressures at the surface. Despite this, NASA is currently working on a conceptual manned mission to Venus, named the High Altitude Venus Operational Concept – (HAVOC).
But how is such a mission even possible? Temperatures on the planet’s surface (about 460°C) are in fact hotter than Mercury, even though Venus is roughly double the distance from the sun. This is higher than the melting point of many metals including bismuth and lead, which may even fall as “snow” onto the higher mountain peaks. The surface is a barren rocky landscape consisting of vast plains of basaltic rock dotted with volcanic features, and several continent-scale mountainous regions.


Venus was once an Earth twin. NASA / JPL

It is also geologically young, having undergone catastrophic resurfacing events. Such extreme events are caused by the build up of heat below the surface, eventually causing it to melt, release heat and re-solidify. Certainly a scary prospect for any visitors.

Hovering in the atmosphere

Luckily, the idea behind NASA’s new mission is not to land people on the inhospitable surface, but to use the dense atmosphere as a base for exploration. No actual date for a HAVOC type mission has been publicly announced yet. This mission is a long term plan and will rely on small test missions to be successful first. Such a mission is actually possible, right now, with current technology. The plan is to use airships which can stay aloft in the upper atmosphere for extended periods of time.
As surprising as it may seem, the upper atmosphere of Venus is the most Earth-like location in the solar system. Between altitudes of 50km and 60km, the pressure and temperature can be compared to regions of the Earth’s lower atmosphere. The atmospheric pressure in the Venusian atmosphere at 55km is about half that of the pressure at sea level on Earth. In fact you would be fine without a pressure suit, as this is roughly equivalent to the air pressure you would encounter at the summit of Mount Kilimanjaro. Nor would you need to insulate yourself as the temperature here ranges between 20°C and 30°C.
The atmosphere above this altitude is also dense enough to protect astronauts from ionising radiation from space. The closer proximity of the sun provides an even greater abundance of available solar radiation than on Earth, which can be used to generate power (approximately 1.4 times greater).
The conceptual airship would float around the planet, being blown by the wind. It could, usefully, be filled with a breathable gas mixture such as oxygen and nitrogen, providing buoyancy. This is possible because breathable air is less dense than the Venusian atmosphere and, as result, would be a lifting gas.
The Venusian atmosphere is comprised of 97% carbon dioxide, about 3% nitrogen and trace amounts of other gases. It famously contains a sprinkling of sulphuric acid which forms dense clouds and is a major contributor to its visible brightness when viewed from Earth. In fact the planet reflects some 75% of the light that falls onto it from the sun. This highly reflective cloud layer exists between 45km and 65km, with a haze of sulphuric acid droplets underneath down to about 30km. As such, an airship design would need to be resistant to the corrosive effect of this acid.
Luckily we already have the technology required to overcome the problem of acidity. Several commercially available materials, including teflon and a number of plastics, have a high acidic resistance and could be used for the outer envelope of the airship. Considering all these factors, conceivably you could go for a walk on a platform outside the airship, carrying only your air supply and wearing a chemical hazard suit.

Life on Venus?

The surface of Venus has been mapped from orbit by radar on the US Magellan mission. However, only a few locations on the surface have ever been visited, by the series of Venera missions of Soviet probes in the late 1970s. These probes returned the first – and so far only – images of the Venusian surface. Certainly surface conditions seem utterly inhospitable to any kind of life.


Venus as seen by Magellan. NASA

The upper atmosphere is a different story however. Certain kinds of extremophile organisms already exist on Earth which could withstand the conditions in the atmosphere at the altitude at which HAVOC would fly. Species such as Acidianus infernus can be found in highly acidic volcanic lakes in Iceland and Italy. Airborne microbes have also been found to exist in Earth’s clouds. None of this proves that life exists in the Venusian atmosphere, but it is a possibility that could be investigated by a mission like HAVOC.
The current climatic conditions and composition of the atmosphere are the result of a runaway greenhouse effect (an extreme greenhouse effect that cannot be reversed), which transformed the planet from a hospitable Earth-like “twin” world in its early history. While we do not currently expect Earth to undergo a similarly extreme scenario, it does demonstrate that dramatic changes to a planetary climate can happen when certain physical conditions arise.
By testing our current climate models using the extremes seen on Venus we can more accurately determine how various climate forcing effects can lead to dramatic changes. Venus therefore provides us with a means to test the extremes of our current climate modelling, with all the inherent implications for the ecological health of our own planet.
We still know relatively little about Venus, despite it being our nearest planetary neighbour. Ultimately, learning how two very similar planets can have such different pasts will help us understand the evolution of the solar system and perhaps even that of other star systems.
Gareth Dorrian, Post Doctoral Research Associate in Space Science, Nottingham Trent University and Ian Whittaker, Lecturer, Nottingham Trent University

This article is republished from The Conversation under a Creative Commons license. Read the original article.