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new study looks at the critical phase during the first 48 hours

At early stages, comatose brains can still distinguish between different sound patterns

this ability progresses over time can predict whether a coma patient will survive and ultimately awaken

very promising tool for prognosis

am led by neuroscientist

of the University of Lausanne in Switzerland studied 30 coma patients who had experienced heart attacks that deprived their brains of oxygen

All the patients underwent therapeutic hypothermia, a standard treatment to minimize brain damage, in which their bodies were cooled to 33° Celsius for 24 hours

played sounds for the patients and recorded their brain activity using scalp electrodes

once in hypothermic conditions during the first 24 hours of coma

again a day later at normal body temperature

sounds were a series of pure tones interspersed with sounds of different pitch, duration or location

brain signals revealed how well patients could discriminate the sounds, compared with five healthy subjects

After three months, the coma patients had either died or awoken

. All the patients whose discrimination improved by the second day of testing survived and awoke from their comas

many of those whose sound discrimination deteriorated by the second day did not survive

all of the patients showed signs of auditory discrimination

suggests that residual auditory function itself does not predict recovery

rather, it’s the progression of function over time that is predictive.

The study couldn’t distinguish whether auditory function initially was preserved due to the hypothermia treatment or was related merely to the early stage of coma

scientists speculate that distracting neural jabber may have been reduced during the hypothermia, making it easier for the patients’ brains to separate sounds

now running a follow-up study with 120 coma patients

whether the results can be replicated in a bigger population

s test could give information about patients who will survive during the first two days of coma

remote telescope located in Siding Spring, Australia to take photos of 2013 UQ4 shortly before dawn in the constellation Cetus.

The asteroid had grown a little fuzz, making the move to comethood

now displays a substantial coma or atmosphere

. No tail is visible yet

it’s still bright enough to see in a 12-inch telescope under dark skie

Assuming the now renamed C/2013 UQ4 continues to spout dust and water vapor, it should brighten to magnitude +11 by month’s end as it moves northward across Pisces and into a dark morning sky

Perihelion occurs on June 5 with the comet reaching magnitude +8-9 by month’s end

Peak brightness of 7th magnitude is expected during its close approach of Earth on July 10 at 29 million miles (46.7 million km).

should be a great summer comet, plainly visible in binoculars from a dark sky

at the rate of some 7 degrees per night! That’s 1/3 of a degree per hour or fast enough to see movement through a telescope in a matter of minutes when the comet is nearest Earth

belongs to a special category of asteroids called damocloids

that have orbits resembling the Halley-family comets with long periods, fairly steep inclinations and highly eccentric orbits (elongated shapes)

Damocloids are thought to be comets that have lost all their fizz.

their volatile ices spent from previous trips around the sun, they stop growing comas and tails and appear identical to asteroids

Occasionally, one comes back to life. It’s happened in at least four other cases and appears to be happening with C/2013 UQ4 as well.

Studies of the comet/asteroid’s light indicate that

is a very dark but rather large object some 4-9 miles (7-15 km) across.

It’s estimated that

takes at least 500 years to make one spin around the sun

interesting possibility of possible interactions of the coma of A1 Siding Spring and the tenuous atmosphere of Mars

researchers considered how active Comet A1 Siding Spring may be at the time of closest approach on October 19th, 2014

Discovered early last year by Robert McNaught from the Siding Spring Observatory in Australia

when it was found that it will pass extremely close to Mars later this year.

with a nominal passage of 138,000 kilometres from Mars. That’s about one third the distance from Earth to the Moon, and 17 times closer than the nearest recorded passage of a comet to the Earth, Comet D/1770 L1 Lexell in 1780.

And although the nucleus will safely pass Mars, the brush with its extended atmosphere might just be detectable by the fleet of spacecraft and rovers in service around Mars

NEOWISE and Hubble are already monitoring the comet for enhanced activity

The Opportunity rover is also still functioning, and Mars Odyssey and ESA’s Mars Express are still in orbit around the Red Planet and sending back data

India’s Mars Orbiter Mission and NASA’s MAVEN orbiter arrive just before the comet.

MAVEN was designed to study the upper atmosphere of Mars, and carries an ion-neutral mass spectrometer (NGIMS) which could yield information on the interaction of the coma with the Martian upper atmosphere and ionosphere.

Proposals for using Earth-based assets for further observations of the comet prior to the event in October are still pending

Amateur observers will be able to follow the approach telescopically

It’s also interesting to consider the potential for interactions of the coma with the surfaces of the moons of Mars as well, though the net amount of water vapor expected to be deposited will not be large

UPDATE: Check out this nifty interactive simulator which includes Comet A1 Siding Springs courtesy of the Solar System Scope

Panoramic Survey Telescope and Rapid Response System (PanSTARRS) based on the summit of Haleakala on the island of Maui

comet brightened ahead of expectations and was first picked up by an amateur astronomer on March 28th of last year

Comet PanSTARRS is already an impressive sight for southern hemisphere observers

Comet PanSTARRS will then begin curving northward during the last week of February

the comet has a hyperbolic orbit inclined 84.2° degrees relative to the ecliptic

On an 110,000+ year orbit, this is more than likely Comet PanSTARRS first journey through the inner solar system

Comet PanSTARRS will reach an altitude of greater than 5° at dusk for northern hemisphere observers based around 30° north latitude looking low to the southwest starting on March 5th.

The comet will then begin gaining altitude

Keep in mind, Daylight Saving Time begins

looking for the comet around 7:00 pm local on the first week of March, it’ll be at 8:00 pm on the second week

After gaining

elevation from our northern hemisphere vantage point

will then begin running roughly parallel to the western horizon on each successive evening for mid-northern latitude observers

This first half of March is also when Comet PanSTARRS will have the potential to appear at its brightest

best case scenario, we’ll have a comet with a -1st magnitude coma and a tail pointing straight up from the horizon like an exclamation point.

worst case situation, we’ll have a +3rd magnitude fuzzy comet only visible through binoculars

if you observe the comet on no other night, be sure to check it out on the evening of March 12-13th

will be joined by a slim crescent Moon just over a day old.

Comet PanSTARRS will then continue its trek northward

for the remainder of March

By May 1st, Comet PanSTARRS will have dipped back down below naked eye visibility

As temperatures inside the body fall, several failsafe systems spring into action

Blood vessels near the skin squeeze tight to hold warmth in, the body starts to shiver and brown fat, a tissue that’s especially plentiful in newborns, starts to produce heat

colleagues bypassed the rats’ defenses against the cold with a compound that’s similar to adenosine, a molecule in the body that signals sleepiness

After about an hour in a room chilled to 15° Celsius, the rats grew lethargic

brain waves slowed, their blood pressure dropped and their heart grew sluggish, occasionally skipping beats

The rats’ core temperature dropped from about 38°  to about 30° C, or 80° Fahrenheit

measured even lower temperatures in further experiments — rats’ core body temperature reached 15° C or about 57° F.

The rats weren’t in a coma, nor were they asleep or truly hibernating

Hibernating animals’ metabolisms plummet and their temperatures sink much lower

an Arctic ground squirrel, for instance, cools to about —3° C when it hibernates

It’s a new state

don’t really know what it is

In the experiment, loud noises and tail pinches failed to arouse the rats.

They didn’t eat or drink. Occasionally, one would slither into a corner, but for the most part, the animals stayed still for up to 6 hours

In unpublished experiments, Tupone has kept the animals in the unresponsive state for 24 hours, he says.

Warming the room coaxed the rats out of their torpor

The recovery process takes about 12 hours, during which the animals ate and drank voraciously

After recovering, the animals were alert, moved around their cages normally and slept when tired

When people have heart attacks or strokes, clinicians can use ice packs or frigid water to chill people and prevent further tissue damage

those methods of cooling take time and can have dangerous side effects

addition of gas and dust should cause the comet’s coma to increase in size.