Thursday, April 9, 2015

Here’s How You Can Watch the SpaceX’s CRS-6 Mission From Your Backyard

Here’s How You Can Watch the SpaceX’s CRS-6 Mission From Your Backyard:



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Dragon approaches the ISS during CRS-5. Image credit: SpaceX.
Hunting for satellites from your backyard can be positively addicting. Sure, the Orion Nebula or the Andromeda Galaxy appear grand… and they’ll also look exactly the same throughout the short span of our fleeting human lifetimes. Since the launch of Sputnik in 1957, humans also have added their own ephemeral ‘stars’ to the sky. It’s fun to sleuth out just what these might be, as they photobomb the sky overhead.  In the coming week, we’d like to turn your attention towards a unique opportunity to watch a high profile space launch approach a well-known orbiting space laboratory.

On Monday, April 13th 2015, SpaceX will launch its CRS-6 resupply mission headed towards the International Space Station. As of this writing, the launch is set for 20:33 Universal Time (UT) or 4:33 PM EDT. This is just over three hours prior to local sunset. The launch window to catch the ISS is instantaneous, and Tuesday April 14th at 4:10 PM EDT is the backup date if the launch does not occur on Monday.



Image credit: Andrew


Dragon chasing the ISS over Ottawa. Image credit and copyright: Andrew Symes
Of course, launches are fun to watch up-close from the Kennedy Space Center. To date, we’ve seen two shuttle launches, one Falcon launch, and the MAVEN and MSL liftoffs headed to Mars from up close, and dozens more from our backyard about 100 miles to the west of KSC. We can typically follow a given night launch right through to fairing and stage one separation with binoculars, and we once even had a serendipitous launch occur during a local school star party! We really get jaded along the Florida Space Coast, where space launches are as common as three day weekend traffic jams elsewhere.

And it’s true that you can actually tell when a launch is headed ISS-ward, as it follows the station up the US eastern seaboard along its steep 52 degree inclination orbit.

On Monday, Dragon launches 23 minutes behind the ISS in its orbit. Viewers up should be able to follow CRS-6 up the U.S. East Coast in the late afternoon sky if it’s clear.



Image credit: Orbitron


The position of the ISS during Monday’s liftoff, plus the trace for the next two orbits, and the position of the day/night terminator at the end of the second orbit. Image credit: Orbitron
And of course, SpaceX will make another attempt Monday at landing its Falcon Stage 1 engine on a floating sea platform, known as the ‘autonomous spaceport drone ship’ (don’t call it a barge) after liftoff.

About 15-20 minutes after liftoff, Europe and the United Kingdom may catch the Dragon and Falcon S2 booster shortly after the ISS pass on the evening of April 13th. Observers ‘across the pond’ used to frequently catch sight of the Space Shuttle and the external fuel tank shortly after launch; such a sight is not to be missed!

Spotting Dragon ‘and friends’ on early orbits may provide for a fascinating show in the evenings leading up to capture and berthing. Typically, a Dragon launch generates four objects in orbit: the Dragon spacecraft, the Falcon Stage 2 booster, and the two solar panel covers. These were very prominent to us as they passed over Northern Maine on first orbit in the pre-dawn sky on the morning of January 10th, 2015. Universe Today science writer Bob King also noted that observers spotted what was probably a venting maneuver over Minnesota on the 2nd pass on the same date.



Image credit: the launch of CRS-2.


The launch of CRS-2. Image credit: David Dickinson
And even after berthing, the Falcon S2 booster and solar panel covers will stay up in orbit, either following or leading the ISS for several weeks before destructive reentry.

Orbits on Monday and Tuesday leading up to capture for Dragon on Wednesday April 15th at 7:14 AM EDT/11:14 UT will be the key times to sight the pair. Capture by the CanadaArm2 will take place over the central Pacific, and the Dragon will be berthed to the nadir Harmony node of the ISS. Dragon will remain attached to the station until May 17th for a subsequent return to Earth. With the end of the U.S. Space Shuttle program in 2011, SpaceX’s Dragon is currently the only vessel with a ‘down-mass’ cargo capability, handy for returning experiments to Earth.



The first few orbits on the night of the 13th for North America include a key pass for the US northeast at 1:04UT (on the 14th)/9:04 PM EDT, and subsequent passes at dusk westward about 90 minutes later. NASA’s Spot the Station App usually lists Dragon passes shortly after launch, as does Heavens-Above and numerous other tracking applications. We’ll also be publishing sighting opportunities for Dragon and the ISS, along with maps on Twitter as @Astroguyz as the info becomes available.

Pre-berthing passes next week favor 40-50 degrees north for evening passes, and 40-50 degrees south for morning viewing.



Image credit: Marco


Dragon/CRS-3 passes over the Netherlands. Image credit: Marco Langbroek
The International Space Station has become a busy place since its completion in 2009. To date, the station has been a port of call for the U.S. Space Shuttles, the Soyuz spacecraft with crews, and Progress, HTV, ATV and Dragon resupply craft.

The current expedition features astronaut Scott Kelly and cosmonaut Mikhail Korniyenko conducting a nearly yearlong stay on the ISS to study the effects that long duration spaceflight has on the human body. Kelley will also break the U.S. duration record by 126 days during his 342 stay aboard the station. The future may see Dragon ferrying crews to the ISS as early as 2017.



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Our ad-hoc satellite imaging rig. Image credit: David Dickinson
And you can always watch the launch live via NASA TV starting at 3:30 PM EDT/19:30 UT.

Don’t miss a chance to catch the drama of the Dragon spacecraft approaching the International Space Station, coming to a sky near you!



About 

David Dickinson is an Earth science teacher, freelance science writer, retired USAF veteran & backyard astronomer. He currently writes and ponders the universe from Tampa Bay, Florida.

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Sunday, April 5, 2015

Infoporn: The Best Images of the Deep Universe (So Far)

Infoporn: The Best Images of the Deep Universe (So Far):

The European Southern Observatory released an incredible set of images today that give the best-ever view of the deep universe. It’s a stunning new peek at one region of space—the Hubble Deep Field South (HDF-S)—that reveals many previously invisible galaxies, along with new information about how they move and how far away they are.

The new discovery is all thanks to the recently-installed MUSE instrument on the ESO’s Very Large Telescope, based on the very high mountain of Cerro Paranal in the very dry Atacama Desert of northern Chile. (High altitude and dry air make for much better astronomical observations.) Until now, astronomers observing the deep universe—including NASA researchers using the Hubble Space Telescope—had to use separate instruments over the course of days to take images of the sky and measure the physical properties of the stuff in it. MUSE (for Multi Unit Spectroscopic Explorer) is the first instrument capable of doing both.

MUSE is two things: a camera that images celestial light-emitting objects, and a spectrograph that measures the wavelength of that light. Using the instrument, astronomers at ESO don’t just receive an image full of pixels. They also receive information about the intensity of the pixel’s component colors—information that lets them learn about a galaxy’s distance from Earth, its elemental composition, and even its rotation. And thanks to adaptive optics that improve resolution, MUSE can see not just bright nearby galaxies, but very faint ones as well.



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The spectrograph in the MUSE instrument creates thousands of individual images of the sky, sorted by wavelength from violet to red. Many galaxies emit only a specific wavelength, flickering into view when the spectrograph isolates that color.  European Southern Observatory


“It was like fishing in deep water, and each new catch generated a lot of excitement and discussion of the species we were finding,” said MUSE principal investigator Roland Bacon in a press release. “The greatest excitement came when we found very distant galaxies that were not even visible in the deepest Hubble image.”

In the latest data, ESO astronomers used MUSE to measure distances for 189 galaxies, including some that are more than 12.8 billion light-years away. MUSE also found more than twenty very faint objects that Hubble had never been able to see before.

Now that MUSE has shown its stuff, Bacon and his colleagues expect to follow up on this data with observations of the Hubble Ultra Deep Field and other ill-known spaces of the universe. ESO has already used the instrument to track the collision of spiral galaxy ESO 137-001 as it crashes spectacularly into the Norma Cluster. Hopefully the images from those observations turn out just as stellar.

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Chilean Volcano Spews a Spectacular Lava Fountain

Chilean Volcano Spews a Spectacular Lava Fountain:

Chilean Volcano Spews a Spectacular Lava Fountain
Villarrica unleashed an impressive lava fountain as the recent unrest continues at the Chilean volcano.

The post Chilean Volcano Spews a Spectacular Lava Fountain appeared first on WIRED.

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Woman Controls a Fighter Jet Sim Using Only Her Mind

Woman Controls a Fighter Jet Sim Using Only Her Mind:

Woman Controls a Fighter Jet Sim Using Only Her Mind
A brain-computer interface lets a quadriplegic woman pilot an F-35 flight simulator with the power of her mind alone.

The post Woman Controls a Fighter Jet Sim Using Only Her Mind appeared first on WIRED.

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NASA Probe Finally Arrives at an Icy Alien World

NASA Probe Finally Arrives at an Icy Alien World:

NASA Probe Finally Arrives at an Icy Alien World
Larry Lebofsky has always been fascinated with Ceres, the biggest object in the asteroid belt between Mars and Jupiter. Even the license plate on his 2005 Toyota Matrix reads “1CERES.” In the late 1970s, the planetary scientist made some of the first observations that suggested Ceres—which is a dwarf planet, like Pluto—has bits of water ice […]

The post NASA Probe Finally Arrives at an Icy Alien World appeared first on WIRED.

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Watch a Mesmerizing Animation of NASA Satellites

Watch a Mesmerizing Animation of NASA Satellites:

Watch a Mesmerizing Animation of NASA Satellites
NASA’s Earth-observing satellites get the dubious honor of staring at us all day. Now, this video of the fleet zipping around the planet is just mesmerizing enough to make us want to do the same.

The post Watch a Mesmerizing Animation of NASA Satellites appeared first on WIRED.

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Alien FAQ: 6 questions about strange cosmic radio bursts

Alien FAQ: 6 questions about strange cosmic radio bursts:



The truth is out there (Image: Universal/Everett/REX)

A report that bursts of radio waves from the distant universe exhibit a weird mathematical pattern have freshly raised hopes that ET might be signalling us. But what's really behind it? Here's our ET FAQ.

1. Is this the first time we think we might have found aliens?
Nope, there have been several false alarms. The most famous is the 72-second Wow! signal, so called because an eager astronomer wrote "Wow!" next to it on a printout from the Ohio State Big Ear Telescope in 1977. It didn't seem to be of this Earth, but it was never seen again.

A few years before that, astronomer Jocelyn Bell thought she may have found the beep-beep-beep of "little green men" when she had actually discovered pulsars, the rapidly rotating corpses of stars that sweep a lighthouse-like beam of radiation as they spin. In the 70s, astronomers thought a Citizen's Band radio could be ET, and flagged the SOHO satellite as a possible signal in the 90s. But their double, triple and quadruple-checking rules meant they found the real culprits before making any announcements.

SETI software now weeds out false alarms pretty fast on its own, and there haven't been any major maybes in more than a decade – until now, perhaps.

2. Could the bursts have natural causes?
Fast radio bursts could have a natural, rather than an artificial, flavour. If a star in our galaxy had a massive flare-up, and the radiation had to tunnel through a bunch of cast-off plasma, the signal could look like it came from much farther away.

Also, if two white dwarf stars – the kind of dead sphere our sun will turn into in a few million years – crash into each other, they explode in a supernova. That blast could release a fast radio burst.

Then there are neutron stars. If two neutron stars – the dense cores of collapsed stars – are about to collide, they might release a radio burst right before they violently merge into one. Alternatively, some neutron stars are so massive that they should have collapsed into black holes, but are rotating too fast to do so. If one of these slows down, it will finally form a black hole, maybe blasting out a burst before it disappears forever.

Still, these don't account for the fast radio bursts' pattern according to any physics we know now.

3. How will we figure out if the creepy pattern is real or not?
First, scientists will have to discover more bursts using lots of different telescopes. Based on how much of the sky telescopes stared at and for how long before we found the 10 known bursts, scientists estimate that 10,000 bursts happen every day. Watching the whole sky all the time we'd catch every one of them, but right now we make discoveries when a scope happens to be pointed at the right place at the right time.

Either these new bursts will fit within the same pattern, adding to the eeriness, or they won't. If not, case closed. But, assuming they match up, we can see if they fit any earthly patterns, like appearing at the same parts of the day-night cycle or aligned with our seconds or minutes, which might imply an earthly origin. This may already be throwing some water on the discovery: the researchers published an update on 30 March suggesting that the signals might arrive according to UTC times, which aliens are unlikely to know about.

4. If it's really a signal from ET, how will we know what they're saying?
Google Translate! Just kidding. For the bursts we've already seen, we'll have to dig around in the existing data – which tells us how strong the radio waves were, at which frequencies, at what times – and see if anything is encoded besides 187.5. In the future, we could try to record more information about the bursts, to see if extra signals are embedded.

Some SETI scientists think it could take us centuries to decode any message we received. We won't have a common language, a common culture, or even common sensory organs. For a while, we may have to be happy to assume they're just saying "Hello!"

5. How else can we find ET?
Rogue radio broadcasts are the traditional signs astronomers look for from aliens – basically because these are the easiest to spot - and specifically, those from known exoplanet systems. The Allen Telescope Array currently does this sort of work from northern California. But search options expand as our technology gets better. As astronomer Jill Tarter is fond of saying, "SETI scientists always reserve the right to get smarter."

We could also look for signs of atmospheric and light pollution on other planets, to see if ET is as environmentally unfriendly as we are. We can look for ultrafast laser pulses that, as far as we know, the universe doesn't create naturally, but which humans – and perhaps aliens – can generate. And aliens who harness their star's energy in a super-evolved version of solar panels called a Dyson sphere would leave a heat signature we could see from far away.

6. What is the most likely explanation?
The only thing we know for sure about fast radio bursts – and this potential pattern – is that they're telling us we don't understand something about the universe. Maybe what we don't understand is that we have cosmic cousins. But more likely, we're missing something fundamental about how pulsars work or what our own satellites are doing. Either we'll learn something about physics, or we'll learn something about interstellar biology. It's win-win.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

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Super-typhoon Maysak looks tranquil from space

Super-typhoon Maysak looks tranquil from space:



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A destructive typhoon currently heading towards the Philippines has been photographed from the International Space Stationmf.gif







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Основатели X-Prize и Google откроют добычу ресурсов на астероидах

Основатели X-Prize и Google откроют добычу ресурсов на астероидах:

Ряд известных предпринимателей, учёных и инженеров, а также легендарный режиссёр Джеймс Кэмерон объявили о постановке грандиозной цели: в самое ближайшее время начать исследование околоземных астероидов с тем, чтобы вскоре перейти к добыче на них различных минералов, воды, а также драгоценных металлов.

Вся работа будет идти под эгидой компании Planetary Resources. Она была создана три года назад Питером Диамандисом (основателем фонда X-Prize, известного по ряду технических конкурсов, например – соревнованию первых в мире частных луноходов) и Эриком Андерсоном (Eric C. Anderson). Последний является одним из основателей компании Space Adventures, известной по продаже туристических билетов на МКС.

Неутомимый Кэмерон стал одним из главных моторчиков и консультантов проекта, только теперь «выходящего на свет». А среди ключевых спонсоров фирмы стоит отметить сооснователя компании Google Лари Пейджа, председателя совета директоров Google Эрика Шмидта и предпринимателя Чарльза Симони (Charles Simonyi). Он, заметим, побывал в космосе дважды, в качестве космического туриста в 2007 и 2009 годах.

Только один 500-метровый астероид, богатый платиной, содержит эквивалент всех металлов платиновой группы, которые люди когда-либо добыли за всю историю, — заявляют авторы проекта в своём обращении. Другие потенциальные ресурсы – палладий, осмий, рутений, иридий, родий, а также моно- и диоксид углерода, метан, азот… (иллюстрации Murphy Elliott, Planetary Resources, NASA).
По информации BBC News, стартовый проект «ресурсов» — запуск первого в мире частного космического телескопа. Если всё пойдёт по плану, этот аппарат должен выйти на орбиту через 18-24 месяца.

Спутник, который уже разрабатывается полным ходом, называется Leo (он же Arkyd Series 100). Этот небольшой аппарат будет использоваться для частных космических исследований (возможности аппарата будут открыто предлагаться публике). Но главная цель телескопа – изучение астероидов в поисках полезных минеральных ресурсов.

Со временем на низкой орбите должна оказаться целая серия таких «дозорных». Совместно они смогут внимательно осмотреть тысячи астероидов, подходящих к Земле достаточно близко, чтобы в будущем к ним можно было с умеренными затратами отправлять беспилотные миссии.

Разрешение нового телескопа должно составить одну угловую секунду (иллюстрации Planetary Resources).
Следующий шаг компании – постройка «перехватчиков» (Interceptor, Arkyd Series 200, рисунок внизу). Эти аппараты должны уметь близко подходить к астероидам для детального картографирования. Спроектированы эти машины будут на основе того же Leo. Только вдобавок телескоп получит двигательную установку и дополнительное научное оборудование.

«Перехватчики» смогут действовать в одиночку или парами. Они будут рассчитаны на полёты к астероидам, которые во время своего путешествия вокруг Солнца сближаются с Землей на расстояние порядка радиуса лунной орбиты. Таких объектов в Солнечной системе большое количество (причём новые открываются регулярно). Между тем они могут содержать немало ценных веществ.

Предварительная миссия к астероиду должна подтвердить, что объект представляет интерес для разработки недр (иллюстрация Planetary Resources).
Дальнейший план вновь предусматривает модернизацию уже освоенного аппарата. Прибавка новой авионики и лазерной системы связи превратит «Перехватчик» в Rendezvous Prospector. Этот аппарат сможет отправляться на исследование намного более далёких астероидов.

Компания Planetary Resources рассчитывает создавать и запускать такие машины по нескольку штук, что сократит расходы на изготовление и снизит риск провала миссии. «Изыскатели» смогут детально анализировать астероиды, их размер, массу и состав. На основе данных от роёв таких машин компания сможет принять решение о разумности посылки к тем или иным небесным горам добывающих роботов.

По идее, межпланетная станция Rendezvous Prospector или Arkyd Series 300 должна использовать основные узлы ранее неоднократно испытанных машин, а потому, по мнению владельцев компании, явит собой пример дешёвых планетарных исследований (иллюстрация Planetary Resources).
Интенсивная разведка ресурсов астероидов должна начаться через пять-десять лет. Вскоре после этого компания рассчитывает перейти к добыче на астероидах воды, а позже — драгоценных и редких металлов. Правда, несмотря на высокую цену платины и элементов-родственников, экономическая оправданность такого шага выглядит весьма спорной, ведь полёты в космос всё ещё дороги.

Но основатели Planetary Resources полагают, что со временем доступ в космос будет дешеветь. И к тому моменту нужно быть готовым перейти от чисто исследовательских полётов к промышленным.

Начнёт компания, по всей видимости, с воды. При благоприятном сочетании факторов (орбита астероида, его размеры и количество льда), привести энное число тонн воды с астероида на околоземную орбиту может оказаться выгоднее, чем поднимать эти тонны из «гравитационного колодца». А уже здесь, у Земли, при помощи солнечных батарей и электролизёров, воду можно разложить на кислород и водород – топливо для ракет, отправляющихся вглубь Солнечной системы.

Вода, доставка которой на орбиту стоит дорого, должна стать одним из первых ресурсов, добываемых в космосе. Учёные знают, что водяной лёд присутствует не только в ядрах комет, но и на астероидах (иллюстрация Planetary Resources).
Орбитальные АЗС могли бы стать опорой для более интенсивного исследования нашего космического окружения. Первый летающий склад горючего Planetary Resources предполагает создать к 2020 году. Некоторые эксперты считают такие сроки слишком оптимистическими. Но в целом картина, нарисованная Диамандисом, Кэмероном и его соратниками выглядит логично.

«Если оглянуться назад в историю, на то, что привело человечество к крупнейшим инвестициям в разведку и транспорт, то мы увидим — это ресурсы, — говорит Диамандис. — Европейцы осваивали новые маршруты ради специй. Первые американские поселенцы шли на запад из-за золота, нефти, древесины и земли».

Основатели «Планетарных ресурсов» не ждут баснословных прибылей в скором времени. Вложенные в проект деньги, по их оценке, начнут возвращаться через десятилетия. Зато потом перспективы открываются заманчивые. Те же драгоценные или редкоземельные металлы могут не только стать хорошим источником дохода. Их массовая добыча способна преобразить технику, сделать дешевле солнечную энергетику и электронику.

В общем, «дорожная карта» Planetary Resources предусматривает сочетание приземлённой коммерции с «возвышенным» научным познанием мира и заботой о прогрессе цивилизации. Любопытно, что в число участников проекта вошли планетолог MIT Сара Сигер (Sara Seager), ветеран NASA, астронавт Томас Джонс (Thomas Jones), ряд учёных и инженеров NASA, принимавших участие в миссиях агентства к астероидам и на Марс. В ролике ниже о планах компании рассказывают её основные фигуры.

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20 марта 2015 года — полное солнечное затмение

20 марта 2015 года — полное солнечное затмение:



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20 марта 2015 года произойдет полное солнечное затмение. Его полную фазу можно будет наблюдать на севере Атлантического океана и в Арктике. Участков суши, на которых Солнце совсем пропадет из вида, совсем немного: это Фарерские острова и архипелаг Шпицберген. Максимальная длительность полной фазы составит 2 минуты 47 секунд. Следующее полное солнечное затмение будет почти через год — 9 марта 2016 года.

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Don’t Blink! April 4th Lunar Eclipse Shortest of the Century

Don’t Blink! April 4th Lunar Eclipse Shortest of the Century:



The phases of a total lunar eclipse. Saturday's eclipse will see the briefest totality in a century. Credit: Keith Burns / NASA


As the Moon slips into Earth’s shadow it will undergo a total eclipse early Saturday morning April 4.  The partial phases will span some 3 1/2 hours, but totality lasts less than five minutes. Credit: Keith Burns / NASA
Get ready for one awesome total lunar eclipse early Saturday morning April 4th. For the third time in less than a year, the Moon dips into Earth’s shadow, its dazzling white globe turning sunset red right before your eyes.  All eclipses are not-to-miss events, but Saturday’s totality will be the shortest in a century. Brief but beautiful – just like life. Read on to find out how to make the most of it.



Four total lunars in succession is called a tetrad. During the 21st century there are nine sets of tetrads. Credit: NASA


Four total lunar eclipses in succession with no partials in between is called a tetrad. The April 4th eclipse is part of a tetrad that started last April and will wrap up on September 28. During the 21st century there will be eight sets of tetrads. Credit: NASA
Lunar eclipses don’t usually happen in any particular order. A partial eclipse is followed by a total is followed by a penumbral and so on. Instead, we’re in the middle of a tetrad, four total eclipses in a row with no partials in between. The final one happens on September 28.  Even more remarkable, part or all of them are visible from the U.S. Tetrads will be fairly common in the 21st century with eight in all. We’re lucky — between 1600 and 1900 there were none! For an excellent primer on the topic check out fellow Universe Today writer David Dickinson’s “The Science Behind the Blood Moon Tetrad“.



The Moon moves out of total eclipse and into partial phases during the second of the four tetrad eclipses on October 8, 2015. Credit: Bob King


The partially eclipsed Moon on October 8, 2015.  For skywatchers across the eastern half of North America, this is about how the Moon will appear shortly before it sets. Those living further west will see totality. Credit: Bob King
Lots of people have taken to calling the tetrad eclipses Blood Moons, referring to the coppery color of lunar disk when steeped in Earth’s shadow and the timing of both April events on the Jewish Passover. Me? I prefer Bacon-and-Eggs Moon. For many of us, the eclipse runs right up till sunrise with the Moon setting in bright twilight around 6:30 a.m. What better time to enjoy a celebratory breakfast with friends after packing away your gear?



Map showing where the April 4 lunar eclipse will be penumbral, partial and total. Inset shows a world map. Credit: Larry Koehn / shadowandsubstance.com


Map showing where the April 4 lunar eclipse will be penumbral, partial and total. World map shown in inset. Credit: Larry Koehn / shadowandsubstance.com Inset: Fred Espenak
But seriously, Saturday morning’s eclipse will prove challenging for some. While observers in far western North America, Hawaii, Japan, New Zealand and Australia will witness the entire event, those in the mountain states will see the Moon set while still in totality. Meanwhile, skywatchers in the Midwest and points East will see only the partial phases in a brightening dawn sky. Here are the key times of eclipse events by time zone:



A total lunar eclipse occurs only during Full Moons when the Sun, Earth and Moon form a straight line. The Moon slips directly behind Earth into its shadow. The outer part of the shadow or penumbra is a mix of sunlight and shadow. The inner cone, called the umbra, the Sun is completely blocked from view. However, light refracted by Earth's atmosphere is bent into the umbra where it colors the eclipsed Moon red.


A total lunar eclipse occurs only during full moon phase when the Sun, Earth and Moon lie in a straight line. The Moon slips directly behind Earth into its shadow. The outer part of the shadow or penumbra is a mix of sunlight and shadow and only partially dark. From  the inner shadow, called the umbra, the Sun is completely blocked from view. A small amount of sunlight refracted or bent by Earth’s atmosphere into the umbra, spills into the shadow, coloring the eclipsed Moon red.
Eclipse Events                                     EDT              CDT              MDT             PDT

Penumbra eclipse begins 5:01 a.m. 4:01 a.m. 3:01 a.m. 2:01 a.m.
Partial eclipse begins 6:16 a.m. 5:16 a.m. 4:16 a.m. 3:16 a.m.
Total eclipse begins ——– ——– 5:58 a.m. 4:58 a.m.
Greatest eclipse ——– ——– 6:00 a.m. 5:00 a.m.
Total eclipse ends ——– ——– 6:03 a.m. 5:03 a.m.
Partial eclipse ends ——— ——– ——– 6:45 a.m.
Penumbra eclipse ends ——— ——— ——– ——–
* During the penumbral phase, shading won’t be obvious until ~30 minutes before partial eclipse.



Partial eclipse, when the Moon first enters Earth's dark, inner shadow called the umbra, begins at 5:16 a.m. CDT near the start of morning twilight. Totality begins at 6:58 a.m. with the Moon already set for the eastern half of the country. Credit: Fred Espenak


Partial eclipse, when the Moon first enters Earth’s dark umbral shadow, begins at 5:16 a.m. CDT near the start of morning twilight. Totality begins at 6:58 a.m. with the Moon already set for the eastern half of the country. Credit: Fred Espenak
This eclipse will also be the shortest total eclipse of the 21st century; our satellite spends just 4 minutes and 43 seconds inside Earth’s umbra or shadow core. That’s only as long as a typical solar eclipse totality. Ah, the irony.

Better have your camera ready or you’ll miss it. The maps below show the maximum amount of the Moon visible shortly before setting from two eastern U.S. cities and the height of the totally eclipsed Moon from two western locations. Click each panel for more details about local circumstances.



The Earth's shadow will take only a small bite out of the Moon before sunrise (6:47 a.m.) as seen from Washington D.C. Source: Stellarium


The Earth’s shadow will take only a small bite out of the Moon before sunrise (6:47 a.m.) as seen from Washington D.C. From all mainland U.S. locations Virgo’s brightest star Spica will appear about 10° to the left of the Moon. Source: Stellarium


Here's the view from Chicago where sunrise occurs at 6:27 a.m. Source: Stellarium


Here’s the view from Chicago where sunrise occurs at 6:27 a.m.  Source: Stellarium


Totality will be visible From Denver, Colorado with the Moon low in the western sky. Source: Stellarium


Totality will be visible From Denver, Colorado with the Moon low in the western sky in morning twilight. Sunrise is 6:42 a.m. Source: Stellarium


Seattle and the West Coast get a great view of totality in a dark sky. The final partial phases will also be visible. Sunrise there is 6:40 a.m. Source: Stellarium


Seattle and the West Coast get a great view of totality in a dark sky. The final partial phases will also be visible. Sunrise there is 6:40 a.m. Source: Stellarium
Now that you know times and shadow coverage, let’s talk about the fun part — what to look for as the event unfolds. You’ll need to find a location in advance with a good view to the southwest as most of the action happens in that direction. Once that detail’s taken care of and assuming clear weather, you can kick back in a folding chair or with your back propped against a hillside and enjoy.



During the early partial phases you may not see the shadowed portion of the Moon with the naked eye. Binoculars and telescopes will show it plainly. But once the Moon's about 50% covered, the reddish-orange tint of the shadowed half becomes obvious. Credit: Jim Schaff


During the early partial phases you may not see the shadowed portion of the Moon with the naked eye. Binoculars and telescopes will show it plainly. But once the Moon is about 50% covered, the reddish-orange tint of the shadowed half becomes obvious. During total eclipse (right), the color is intense.  Credit: Jim Schaff
The entire eclipse can be enjoyed without any optical aid, though I recommend a look through binoculars now and then. The eclipsed Moon appears distinctly three-dimensional with only the slightest magnification, hanging there like an ornament among the stars. The Earth’s shadow appears to advance over the Moon, but the opposite is true; the Moon’s eastward orbital motion carries it deeper and deeper into the umbra.

Nibble by nibble the sunlit Moon falls into shadow. By the time it’s been reduced to half, the shaded portion looks distinctly red even to the naked eye. Notice that the shadow is curved. We live on a spherical planet and spheres cast circular shadows. Seeing the globe of Earth projected against the Moon makes the roundness of our home planet palpable.



Artist view of Earth totally eclipsing the sun as viewed from the moon. Low angled sunlight filtered by our atmosphere is reddened in exactly the same way a setting sun is reddened. That red light bathes the moon’s surface which reflects a bit of it back toward Earth, giving us a red moon during totality.


A simulated view looking back at Earth from the Moon during a total lunar eclipse on Earth. Sunlight grazing Earth’s circumference gets filtered by our atmosphere in exactly the same way the setting or rising Sun looks red. All the cooler colors have been scattered away by air and Red light, bent into the umbra by atmospheric refraction, bathes the lunar surface in red. As you might have guessed, when we see a total lunar eclipse on Earth, lunar inhabitants see a total eclipse of the Sun by Earth. Source: Stellarium
When totality arrives, the entire lunar globe throbs with orange, copper or rusty red. These sumptuous hues originate from sunlight filtered and bent by Earth’s atmosphere into the umbral shadow. Atmospheric particles have removed all the cooler colors, leaving the reds and oranges from a billion sunrises and sunsets occurring around the planet’s circumference. Imagine for a moment standing on the Moon looking back. Above your head would hang the black disk of Earth, nearly four times the size of the Moon in our sky, ringed by a narrow corona of fiery light.

Color varies from one eclipse to the next depending on the amount of water, dust and volcanic ash suspended in Earth’s atmosphere. The December 30, 1982 eclipse was one of the darkest in decades due to a tremendous amount of volcanic dust from the eruption of the Mexican volcano El Chichon earlier that year.

The more particles and haze, the greater the light absorption and darker the Moon. That said, this eclipse should be fairly bright because the Moon does not tread deeply into Earth’s shadow. It’s in for a quick dip of totality and then resumes partial phases.



The Moon's color can vary from yellow-orange to dark, smoky brown during totality depending on the state of the atmosphere. You can also see lots of stars in the sky right up to the Moon's edge when it's in Earth's shadow. This photo from last April's eclipse. Credit: Bob King


The Moon’s color can vary from yellow-orange to dark, smoky brown during totality depending on the state of the atmosphere. You can also see lots of stars in the sky right up to the Moon’s edge when it’s in Earth’s shadow. This photo from last April’s eclipse. Spica is below the Moon and Mars to the right. Credit: Bob King
It’s northern edge, located close to the outer fringe of Earth’s umbra, should appear considerably brighter than the southern, which is closer to the center or darkest part of the umbra.



Earth's shadow exposed! During a lunar eclipse that occurs at dusk or dawn (like the April 4th one and this one last October) we have the rare opportunity to see Earth's shadow on the distant Moon at the same time it's visible as a dark purple band cast on the upper atmosphere as seen here on October 8, 2015. Credit: Bob King


Earth’s shadow exposed! When a lunar eclipse occurs at dusk or dawn we have the rare opportunity to see Earth’s shadow on the distant Moon at the same time it’s visible as a dark purple band cast on the upper atmosphere as seen here on October 8, 2015. Credit: Bob King
Besides the pleasure of seeing the Moon change color, watch for the sky to darken as totality approaches. Eclipses begin with overwhelming moonlight and washed out, star-poor skies. As the Moon goes into hiding, stars return in a breathtaking way over a strangely eerie landscape. Don’t forget to turn around and admire the glorious summer Milky Way rising in the eastern sky.

Lunar eclipses remind us we live in a Solar System made of these beautiful, moving parts that never fail to inspire awe when we look up to notice.

In case you can’t watch the eclipse from your home due to weather or circumstance, our friends at the Virtual Telescope Project  and SLOOH will stream it online.



About 

I'm a long-time amateur astronomer and member of the American Association of Variable Star Observers (AAVSO). My observing passions include everything from auroras to Z Cam stars. Every day the universe offers up something both beautiful and thought-provoking. I also write a daily astronomy blog called Astro Bob.

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Seeking Ceres: Following the Brave New World Through 2015

Seeking Ceres: Following the Brave New World Through 2015:



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A misshapen crescent Ceres as seen from NASA’s Dawn spacecraft. Image credit: NASA/JPL/Caltech/UCLA/DLR/IDA
A little world is making big headlines in 2015. NASA’s Dawn spacecraft entered orbit around 1 Ceres on March 6th, 2015, gaving us the first stunning images of the ~900 kilometre diameter world. But whether you refer to Ceres as a dwarf planet, minor planet, or the king of the asteroid belt, this corner of the solar system’s terra incognita is finally open for exploration. It has been a long time coming, as Ceres has appeared as little more than a wandering, star-like dot in the telescopes of astronomers for over two centuries since discovery.



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The orbit of 1 Ceres. Credit: NASA/JPL
And the good news is, you can observe Ceres from your backyard if you know exactly where to look for it with binoculars or a small telescope. We’ll admit, we had an ulterior motive on pulling the trigger on this post three months prior to opposition on July 24th, as Dawn will soon be exiting its ‘shadow phase’ and start unveiling the world to us up close. The first science observations for Dawn begin in mid-April.



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The path of Ceres through the remainder of 2015. Credit: Starry Night Software.
Ceres spends all of 2015 looping through the constellations of Capricornus, Microscopium and Sagittarius. This places it low to the south for northern hemisphere observers on April 1st in the early morning sky. Ceres will pass into the evening sky by mid-summer. Ceres orbits the Sun once every 4.6 years in a 10.6 degree inclination path relative to the ecliptic that takes it 2.6 AU to 3 AU from the Sun. The synodic period of Ceres is, on average, 467 days from one opposition to the next.



Ceres


Ceres, Vesta and Mars group together in 2014. Image credit and copyright: Mary Spicer
Shining at magnitude +8, April 1st finds Ceres near the Capricornus/Sagittarius border. Ceres can reach magnitude +6.7 during a favorable opposition. Note that Ceres is currently only 20 degrees east of the position of Nova Sagittarii 2015 No. 2, currently still shining at 4th magnitude. June 29th and November 25th are also great times to hunt for Ceres in 2015 as it loops less than one degree past the 4th magnitude star Omega Capricorni.



June 30


Ceres meets up with Omega Capricorni on June 29th. Credit: Stellarium.
You can nab Ceres by carefully noting its position against the starry background from night to night, either by sketching the suspect field, or photographing the region. Fans of dwarf planets will recall that 1 Ceres and 4 Vesta fit in the same telescopic field of view last summer, and now sit 30 degrees apart. Ceres is now far below the ecliptic plane, but will resume getting occulted by the passing Moon on February 3rd, 2017.



Left


The Palermo transit instrument used to discover Ceres. From Della Specola Astronomica (1792)
Ceres was discovered by Giuseppe Piazzi on the first day of the 19th century on January 1st, 1801. Ceres was located on the Aries/Cetus border just seven degrees from Mars during discovery. Piazzi wasn’t even on the hunt for new worlds at the time, but was instead making careful positional measurements of stars with the 7.5 centimetre Palermo Circle transit telescope.



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A 1802 publication by Piazzi describing his discovery of Ceres. Credit: Image in the Public Domain.
At the time, the discovery of Ceres was thought to provide predictive proof of the Titus-Bode law: here was a new planet, just where this arcane numerical spacing of the planets said it should be. Ceres, however, was soon joined by the likes of Juno, Pallas, Vesta and many more new worldlets, as astronomers soon came to realize that the solar system was not the neat and tidy place that it was imagined to be in the pre-telescopic era.

To date, the Titus-Bode law remains a mathematical curiosity, which fails to hold up to the discovery of brave new exoplanetary systems that we see beyond our own.



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Piazzi’s 1801 log describing the motion of Ceres against the starry background. Credit: Monatliche Correspondenz
The view from Ceres itself would be a fascinating one, as an observer on the Cererian surface would be treated to recurrent solar transits of interior solar system worlds. Mercury would be the most frequent, followed by Venus, which transits the Sun as seen from Ceres 3 times in the 21st century: August 1st, 2042, November 19th, 2058 and February 13th 2068. Mars actually transits the Sun as seen from Ceres even earlier on June 9th, 2033. Curiously, we found no transits of the Earth as seen from Ceres during the current millennium from 2000 to 3000 AD!



From Ceres, Jupiter would also appear 1.5’ in diameter near opposition, as opposed to paltry maximum of 50” in size as seen from the Earth. This would be just large enough for Jupiter to exhibit a tiny disk as seen from Ceres with the unaided eye. The four major Galilean moons would be visible as well.



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The 2033 solar transit of Mars as seen from Ceres. Credit: Starry Night Education Software.
The mysteries of Ceres beckon. Does the world harbor cryovolcanism? Just what are those two high albedo white dots? Are there any undiscovered moons orbiting the tiny world? If a fair amount of surface ice is uncovered, Ceres may soon become a more attractive target for human exploration than Mars.

All great thoughts to ponder, as this stellar speck in the eyepiece of your backyard telescope becomes a brand new world full of exciting possibilities.



About 

David Dickinson is an Earth science teacher, freelance science writer, retired USAF veteran & backyard astronomer. He currently writes and ponders the universe from Tampa Bay, Florida.

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