Category Archives: Astronomy

Astronomy

Hubble: “The ghost of Cassiopeia”

The Hubble space telescope offers a great view of the Ghost Nebula:

The ghost of Cassiopeia

IC 63 — nicknamed the Ghost Nebula — is about 550 light-years from Earth. The nebula is classified as both a reflection nebula — as it is reflecting the light of a nearby star — and as an emission nebula — as it releases hydrogen-alpha radiation. Both effects are caused by the gigantic star Gamma Cassiopeiae. The radiation of this star is also slowly causing the nebula to dissipate. [Higher-res images]
About 550 light-years away in the constellation of Cassiopeia lies IC 63, a stunning and slightly eerie nebula. Also known as the ghost of Cassiopeia, IC 63 is being shaped by radiation from a nearby unpredictably variable star, Gamma Cassiopeiae, which is slowly eroding away the ghostly cloud of dust and gas. This celestial ghost makes the perfect backdrop for the upcoming feast of All Hallow’s Eve — better known as Halloween.

The constellation of Cassiopeia, named after a vain queen in Greek mythology, forms the easily recognisable “W” shape in the night sky. The central point of the W is marked by a dramatic star named Gamma Cassiopeiae.

This video zooms in on the emission and reflection nebula IC 63 — nicknamed the Ghost Nebula — about 550 light-years away. It starts with a view of the night sky as seen from the ground. It then zooms through observations from the Digitized Sky Survey 2, and ends with a view of the nebula obtained with the NASA/ESA Hubble Space Telescope. Credit: Hubble, Digitized Sky Survey 2, N. Risinger (skysurvey.org). Music: Astral Electronic.

The remarkable Gamma Cassiopeiae is a blue-white subgiant variable star that is surrounded by a gaseous disc. This star is 19 times more massive and 65 000 times brighter than our Sun. It also rotates at the incredible speed of 1.6 million kilometres per hour — more than 200 times faster than our parent star. This frenzied rotation gives it a squashed appearance. The fast rotation causes eruptions of mass from the star into a surrounding disk. This mass loss is related to the observed brightness variations.

The radiation of Gamma Cassiopeiae is so powerful that it even affects IC 63, sometimes nicknamed the Ghost Nebula, that lies several light years away from the star. IC 63 is visible in this image taken by the NASA/ESA Hubble Space Telescope.

This image shows the sky around the nebula IC 63, nicknamed the Ghost Nebula. It was created from images forming part of the Digitized Sky Survey 2. The field of view is dominated by the bright star Gamma Cassiopeiae, which is having a profound influence on IC 63. IC 63 is only one of several nebulous structures surrounding Gamma Cassiopeiae — all of which are affected by the radiation emitted by the blue-white subgiant star. Credit: ESA/Hubble, NASA, Digitized Sky Survey 2. Acknowledgement: Davide de Martin [Higher-res images]
The colours in the eerie nebula showcase how the nebula is affected by the powerful radiation from the distant star. The hydrogen within IC 63 is being bombarded with ultraviolet radiation from Gamma Cassiopeiae, causing its electrons to gain energy which they later release as hydrogen-alpha radiation — visible in red in this image.

This hydrogen-alpha radiation makes IC 63 an emission nebula, but we also see blue light in this image. This is light from Gamma Cassiopeiae that has been reflected by dust particles in the nebula, meaning that IC 63 is also a reflection nebula.

This colourful and ghostly nebula is slowly dissipating under the influence of ultraviolet radiation from Gamma Cassiopeiae. However, IC 63 is not the only object under the influence of the mighty star. It is part of a much larger nebulous region surrounding Gamma Cassiopeiae that measures approximately two degrees on the sky — roughly four times as wide as  the full Moon.

This video pans across the nebula IC 63, often nicknamed the Ghost Nebula. This nebula is classified as both an emission and a reflection nebula. The hydrogen within IC 63 is being bombarded with radiation from the nearby star Gamma Cassiopeiae, causing its electrons to gain energy which they later emit as hydrogen-alpha radiation — visible in red in this image. The blue parts of IC 63 are created by dust particles in the nebula which reflect the light from Gamma Cassiopeiae. Credit: Hubble. Music: Johan B. Monell (www.johanmonell.com).

This region is best seen from the Northern Hemisphere during autumn and winter. Though it is high in the sky and visible all year round from Europe, it is very dim, so observing it requires a fairly large telescope and dark skies.

From above Earth’s atmosphere, Hubble gives us a view that we cannot hope to see with our eyes. This photo is possibly the most detailed image that has ever been taken of IC 63, and it beautifully showcases Hubble’s capabilities.

More information

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

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Astronomy

ESO: Watching stars form in the Skull and Crossbones Nebula

The latest report from the European Southern Observatrory (ESO):

The Pirate of the Southern Skies

This vivid picture of an active star forming region — NGC 2467, otherwise known as the Skull and Crossbones nebula — is as sinister as it is beautiful. This image of dust, gas and bright young stars, gravitationally bound into the form of a grinning skull, was captured with the FORS instrument on ESO’s Very Large Telescope (VLT). Whilst ESO’s telescopes are usually used for the collection of science data, their immense resolving power makes them ideal for capturing images such as this — which are beautiful for their own sake. [Higher-res images]
FORS2, an instrument mounted on ESO’s Very Large Telescope, has observed the active star-forming region NGC 2467 — sometimes referred to as the Skull and Crossbones Nebula. The image was captured as part of the ESO Cosmic Gems Programme, which makes use of the rare occasions when observing conditions are not suitable for gathering scientific data. Instead of sitting idle, the ESO Cosmic Gems Programme allows ESO’s telescopes to be used to capture visually stunning images of the southern skies.

This zoom video starts with a wide view of the Milky Way and ends with a close-up look at a vivid picture of an active star forming region — NGC 2467, otherwise known as the Skull and Crossbones nebula. This image of dust, gas and bright young stars, gravitationally bound into the form of a grinning skull, was captured with the FORS instrument on ESO’s Very Large Telescope (VLT). Whilst ESO’s telescopes are usually used for the collection of science data, their immense resolving power makes them ideal for capturing images such as this — which are beautiful for their own sake. Credit: ESO/Digitized Sky Survey 2/N. Risinger (skysurvey.org). Music: astral electronic

This vivid picture of an active star-forming region — NGC 2467, sometimes referred to as the Skull and Crossbones Nebula — is as sinister as it is beautiful. This image of dust, gas and bright young stars, gravitationally bound into the form of a grinning skull, was captured with the FORS instrument on ESO’s Very Large Telescope (VLT).  Whilst ESO’s telescopes are usually used for the collection of science data, they can also capture images such as this — which are beautiful for their own sake.

It is easy to see the motivation for the nickname Skull and Crossbones. This young, bright formation distinctly resembles an ominous hollow face, of which only the gaping mouth is visible here. NGC 2467 skulks in the constellation Puppis, which translates rather unromantically as The Poop Deck.

This vivid picture of an active star forming region — NGC 2467, otherwise known as the Skull and Crossbones nebula — is as sinister as it is beautiful. This image of dust, gas and bright young stars, gravitationally bound into the form of a grinning skull, was captured with the FORS instrument on ESO’s Very Large Telescope (VLT). Whilst ESO’s telescopes are usually used for the collection of science data, their immense resolving power makes them ideal for capturing images such as this — which are beautiful for their own sake. The image is a colour composite made from exposures from the Digitized Sky Survey 2 (DSS2), and shows the region surrounding NGC 2467. The field of view is approximately 2.4 x 2.0 degrees. [Higher-res images]
This nebulous collection of stellar clusters is the birthplace of many stars, where an excess of hydrogen gas provided the raw material for stellar creation. It is not, in fact, a single nebula, and its constituent stellar cluster are moving at different velocities. It is only a fortuitous alignment along the line of sight from the Earth that makes the stars and gas form a humanoid face. This luminous image might not tell astronomers anything new, but it provides us all with a glimpse into the churning southern skies, bright with wonders invisible to the human eye.

Puppis is one of three nautically named constellations that sail the southern skies, and which used to make up the single, giant Argo Navis constellation, named after the ship of the mythical Jason and the Argonauts. Argo Navis has since been divided into three: Carina (the keel), Vela (the sails) and Puppis, where this nebula finds its home.  Whilst a heroic figure, Jason is most famous for his theft of the golden fleece, so NGC 2467 rests not only in the midst of a vast celestial ship, but amongst thieves — an appropriate abode for this piratical nebula.

This image was created as part of the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.

This pan video explores a vivid active star forming region — NGC 2467, otherwise known as the Skull and Crossbones nebula. This image of dust, gas and bright young stars, gravitationally bound into the form of a grinning skull, was captured with the FORS instrument on ESO’s Very Large Telescope (VLT). Whilst ESO’s telescopes are usually used for the collection of science data, their immense resolving power makes them ideal for capturing images such as this — which are beautiful for their own sake. Credit: ESO. Music: Johan B. Monell (www.johanmonell.com)

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Astronomy, Exoplanets

Hubble: Observations indicate a Neptune-sized moon orbiting Jupiter-sized exoplanet

Researchers using the Hubble telescope appear to have observed a gas-giant sized Moon orbiting an even larger planet in another star system:

Hubble finds compelling evidence for a moon outside the Solar System
Neptune-sized moon orbits Jupiter-sized planet

This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System. Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis. [Higher-res images]
Using the NASA/ESA Hubble Space Telescope and older data from the Kepler Space Telescope two astronomers have found the first compelling evidence for a moon outside our own Solar System. The data indicate an exomoon the size of Neptune, in a stellar system 8000 light-years from Earth. The new results are presented in the journal Science Advances.

The hunt for exoplanets — planets outside our own Solar System — provided its first results only 30 years ago. While astronomers now find these planets on a regular basis, the search for moons orbiting exoplanets wasn’t successful — until today.

This animation demonstrates how the measured light curve from the star Kepler-1625b led to the conclusion that the system may consist of not only a planet, but also at least one moon.

When the planet moves in front of its parent star a tiny portion of its light is blocked by the disc of the planet, so we observe a dimming of the light from the star. Right after the exoplanet has finished its transit the starlight is seen to dim slightly again, suggesting the presence of a moon trailing the planet. Credit: ESA/Hubble, L. Calçada

In 2017 NASA’s Kepler Space Telescope detected hints of an exomoon orbiting the planet Kepler-1625b. Now, two scientists from Columbia University in New York (USA) have used the incomparable capabilities of the NASA/ESA Hubble Space Telescope to study the star Kepler-1625, 8000 light-years away, and its planet in more detail. The new observations made with Hubble show compelling evidence for a large exomoon orbiting the only known planet of Kepler-1625. If confirmed, this would be the first discovery of a moon outside our Solar System.

The candidate moon, with the designation Kepler-1625b-i, is unusual because of its large size; it is comparable in diameter to the planet Neptune. Such gargantuan moons are unknown in our own Solar System.

“This may yield new insights into the development of planetary systems and may cause astronomers to revisit theories of how moons form,”

Alex Teachey, a graduate student who led the study, explained excitedly [1].

Like its moon, Kepler-1625b is also bigger than its counterparts in the Solar System. The exoplanet is a gas giant, several times more massive than Jupiter [2]. It orbits its parent star at a distance similar to the distance between the Sun and Earth, which puts it — and its candidate moon — at the inner edge of the habitable zone of the star system [3].

To find evidence for the existence of the exomoon, the team observed the planet while it was in transit in front of its parent star, causing a dimming of the starlight.

“We saw little deviations and wobbles in the light curve that caught our attention,”

David Kipping, second author of the study, said.

The planet was observed by Hubble before and during its 19-hour-long transit. After the transit ended, Hubble detected a second and much smaller decrease in the star’s brightness approximately 3.5 hours later, consistent with the effect of a moon trailing the planet.

“It was definitely a shocking moment to see that light curve — my heart started beating a little faster and I just kept looking at that signature,”

David Kipping described his feelings. Unfortunately, the scheduled Hubble observations ended before the complete transit of the moon could be captured.

In addition to this second dip in the light curve, Hubble provided compelling supporting evidence for the moon hypothesis by detecting the planet’s transit more than an hour earlier than predicted. This is consistent with a model of the system in which the planet and its moon orbit a common centre of gravity, causing the planet to wobble away from its predicted location [4].

In principle this anomaly could also be caused by the gravitational pull of a hypothetical second planet in the system, but the Kepler Space Telescope found no evidence for additional planets around the star during its four year mission. Still, further observations by Hubble are needed to fully confirm the existence of Kepler-1625b-i.

“If confirmed, Kepler-1625b-i will certainly provide an interesting puzzle for theorists to solve,” said Kipping. Teachey concluded: “It is an exciting reminder of how little we really know about distant planetary systems and the great spirit of discovery exoplanetary science embodies.”

Notes

[1] The moons of Jupiter and Saturn likely formed through the agglomeration into a disc of material orbiting the planets, so it is possible that this exomoon also formed in a circumplanetary disc. Another possibility is that a passing object was captured by the planet’s gravity. Tidal forces between the two objects would rob momentum from the less massive companion and eventually pull it into a permanent orbit. There are no indications of tidal capture among our Solar System’s moons. In the case of the Earth–Moon system, an early collision with a larger body is hypothesised to have blasted off material that later coalesced into a moon. However, Kepler-1625b and its candidate moon are gaseous, not rocky, so such a collision would not have led to the condensation of a satellite.

[2] Despite its size, the mass of the candidate moon is estimated to be only 1.5 percent of the mass of its companion planet. This value is close to the mass ratio between Earth and the Moon.

[3] While both the planet and its candidate moon are within the habitable zone, where moderate temperatures allow for the existence of liquid water, both bodies are considered to be gaseous and therefore unsuitable for life as we know it.

[4] A distant observer watching the Earth and Moon transit the Sun would note similar anomalies in the timing of Earth’s transit.

More information

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The results were presented in the paper Evidence for a large exomoon orbiting Kepler-1625b in the journal Science Advances.

The team of astronomers in this study consists of Alex Teachey and David M. Kipping (Columbia University, New York, USA).

Image credit: NASA, ESA

Astronomy

Videos: October 2018 night sky highlights

** NASA JPL posts this preview of highlights of the October night sky:

**  The Hubble Space Telescope Institute provides this October preview:

This October, look for Pegasus, the great winged horse of Greek mythology, prancing across the autumn night sky. Binoculars and small telescopes will reveal the glowing nucleus and spiral arms of the Andromeda Galaxy, and the Orionid meteor shower peaks on the night of October 21.

 

Activism, Astronomy, Contests and Games

“First Women on the Moon” Essay Contest

An announcement from the International Lunar Observatory Association (ILOA):

‘FIRST WOMEN ON THE MOON’ ESSAY CONTEST RULES

100-Word Submission Due 5 October 2018
Grand Prize: All-expenses-paid participation at Galaxy Forum Hainan, China 4-7 December 2018 

INTRODUCTION: The first men walked upon the Moon in 1969. Since then, 61 women from multiple nations have traveled into Space. Several countries are now actively aiming for the Moon, including a Human Return to the Moon. The First Woman to the Moon is walking among us.

GRAND PRIZE: Winner will attend all sessions, ceremonies and activities at ILOA Galaxy Forum Hainan 2018, China on 4-7 December, and participate in the “First Women on the Moon” special luncheon panel featuring Astronauts Soyeon Yi, Naoko Yamazaki, other women Astronauts from China and USA (TBD); and potentially an Apollo Moonwalker. Direct purchase by ILOA will cover round-trip regular class airline travel to Hainan Island, hotel accommodation at Hilton Wenchang, Galaxy Forum registration fee and meals. Reimbursement for reasonable traveling incidentals such as meals at airports and ground transportation will be covered. Reimbursement for passport and visa, and expedited fees, will also be provided, if necessary.

HOW TO ENTER: Describe in 100 words or less why you would like to be the First Woman or one of the First Women on the Moon, and the significance of the First Woman landing on the Moon. Send your essay with subject line of “First Women on the Moon” to 1stWomenontheMoon@iloa.org along with your full name, age, mailing address, and telephone number listed at the bottom.

DEADLINE: All email entries due by 5 October 2018, 12:00 Hawaii Standard Time (UTC-10) to email address: 1stWomenontheMoon@iloa.org

ELIGIBILITY: Contest is open to all women 21 years of age or older by 1 December 2018, from any country, nation, continent, background and ability. English is the main language of Galaxy Forum Hainan, therefore we ask for essays to be written in English. Contestant must already have or be eligible to receive a Passport and a Visa to travel to Hainan, China for 4-7 December 2018.

WINNER SELECTION: ILOA Associates will review and select a Contest Winner based on the merit of the written essay.

WINNER NOTIFICATION: Grand Prize Winner will be informed via email or phone by 17 October 2018 and announced to media shortly thereafter. A Second Grand Prize or Runner Up may be chosen at ILOA’s discretion and may include an identical Grand Prize trip to ILOA Galaxy Forum Hainan, publicity of contestant’s essay, and / or a ‘First Women on the Moon’ mailing packet with posters and pins designed by ILOA.

SPONSOR:  International Lunar Observatory Association (ILOA) an interglobal enterprise incorporated in Hawai’i as a 501(c)(3) non-profit to realize the multifunctional ILO — to advance human knowledge of the Cosmos through observation from our Moon, and to participate in lunar base build-out with Aloha. The ILOA also since 2008 has cosponsored with its Space Age Publishing Company affiliate an international series of 85 Galaxy Forums.

ODDS OF WINNING: The odds of winning this Contest will depend upon the number of Contest Contestants. 

GALAXY FORUM HAINAN 2018, CHINA: Full public details for Galaxy Forum Hainan 2018 may be found here: https://galaxyforum.org/galaxy-forum-china-2018-hainan/

FURTHER INFORMATION AND CONTACT: Please visit the websites for International Lunar Observatory Association, Galaxy Forum, or affiliated Space Age Publishing Company. ILOA may or may not have time or ability to respond to contestant questions, however contestants are welcome to send questions to 1stWomenontheMoon@iloa.org

GENERAL CONDITIONS & BINDING AGREEMENTS: By entering this CONTEST (the “Contest”) and accepting the terms herein, you (the “Contestant” or “Winner”) agree to be bound by the conditions and terms outlined in this document. ILOA is not liable for any problems that may prevent your entry in the contest, or for events that delay or cancel the contest. No purchase is necessary to win.

These rules are subject to change and interpretation at the discretion of ILOA. Failure to adhere to the contest rules will be subject for removal from the contest.

Contestant is solely responsible for reviewing and understanding the policies regarding eligibility to participate in the Contest, its rules, regulations and responsibilities.

Contestant / Winner agrees that neither ILOA nor any affiliate, officer, director, employee, attorney, or agent of ILOA shall have any liability for any indirect or direct damages, inconveniences or issues that may arise from sources including, but not limited to, media attention, publicity, travel, ‘acts of god’, force majeure, or personal medical problems / sickness that could occur; the Contestant / Winner hereby waives, releases, and agrees not to sue any of them upon, any claim for any special, indirect, incidental, or consequential damages suffered or incurred by this Contest or ILOA in connection with, arising out of, or in any way related to this Contest.

CONTEST CANCELLATION, SUSPENSION OR MODIFICATION: ILOA reserves the right to cancel, terminate, modify or suspend this Contest if the Contest is not capable of being completed as planned for any reason. The decision of ILOA to cancel, terminate, modify or suspend this Contest shall be final in all respects.

PUBLICITY RELEASE: Unless prohibited by applicable law, Contestant / Winner authorizes and irrevocably grants to ILOA permission to, from time to time, reference and discuss Contestant / Winner and their participation in the Contest on-air and/or on their website(s) in photographs, video recordings, digital images, audio recordings, as well as in publications, newsletters, news releases, other printed materials, and in materials made available on the Internet or in other media now known or hereafter developed for any purpose ILOA deems proper. Such reference and discussion may involve Contestant’s name and voice, and other personal/biographical material or their participation. 

RULES CHANGES AND INTERPRETATIONS: ILOA reserves the right in its sole discretion to supplement or make changes to the rules of this Contest at any time without notice. ILOA reserves the right in its sole discretion to interpret the rules of any contest, and such interpretation shall be binding upon all contestants.

CONTEST ENTITY AND IMMEDIATE FAMILY MEMBER DISQUALIFICATION: The officers, directors, employees, contractors, and agents of ILOA, as well as their immediate family members (and those living in the same household, whether or not related), are prohibited from participating in this Contest and do not qualify as Contestants. “Immediate family members” shall include spouses, siblings, parents, children, grandparents, and grandchildren, whether as “in-laws”, or by current or past marriage, remarriage, adoption, co-habitation or other familial extension.

FIRST WOMAN ON THE MOON POLL: ILOA invites anonymous voting from anyone for the “First Woman on the Moon” poll located on Space Calendar http://www.spacecalendar.com/ and Lunar Enterprise Daily http://www.lunarenterprisedaily.com/

Participating in this poll does not in any way affect this Contest or its results.

MEDIA INQUIRES: We welcome any MEDIA inquiries to be sent directly to ILOA at info@iloa.org

MAHALO / THANK YOU: ILOA sends a warm Mahalo and Thank You to all Contestants who enter this Contest and to all readers that share and support the ‘First Women on the Moon’ vision for the benefit of all humankind. Ad Astra with Aloha!

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