Wandering through the realms of the cosmos, pondering its huge vastness

Asteroids, Comets and Planetoids

A Fifth Moon Around Pluto!

July 11, 2012: A team of astronomers using NASA’s Hubble Space Telescope reported the discovery of another new moon orbiting the icy dwarf planet Pluto, meaning the dwarf planet now has 5 moons. So there is Charon, Hydra, Nix, P4 and Yet-to-be-named moon. The 4th moon, P4, was only discovered about a year ago.

The “new” moon is estimated to be irregular in shape and 6 to 15 miles across. It is in a 58,000-mile-diameter circular orbit around Pluto that is assumed to be co-planar with the other satellites in the system.

Pluto’s entire moon system is believed to have formed by a collision between the dwarf planet and another planet-sized body early in the history of the solar system. The smashup flung material that coalesced into the family of satellites observed around Pluto.

Scientists are searching for more possible moons orbiting Pluto and also signs of a possible debris field generated by the theoretical impact billions of years ago.

Meanwhile, this recent discovery has raised the hopes of many Pluto supporters that they call for its reinstatement as the 9th planet.

But would Pluto’s 5th moon make it a Planet?

Unfortunately, no.

This image, taken by NASA's Hubble Space Telescope, shows five moons orbiting the distant, icy dwarf planet Pluto. The green circle marks the newly discovered moon, designated P5, as photographed by Hubble's Wide Field Camera 3 on July 7, 2012.Despite of some determined lobbying by die-hard supporters to change its dwarf planet status, more moons around Pluto  won’t change its classification.

According to Michael Brown, an astronomer at the California Institute of Technology, the discovery of Eris, a rocky object about Pluto’s size with approximately 25% more mass, was a major factor in the IAU’s decision to reassess exactly what constitutes a planet. Hence, the controversial decision of demoting Pluto.

The IAU ruled that to be called a planet, an object has to meet three conditions:

  • It needs to be in orbit around the Sun.
  • It needs to have enough gravity to pull itself into a spherical shape.
  • It needs to have “cleared the neighborhood” of its orbit.
Pluto satisfied all the conditions, except the third one. Any object that doesn’t meet this third criterion is considered a dwarf planet. And so, Pluto is a dwarf planet.  Even with Pluto’s five moons , it doesn’t “clear the neighborhood.” There are still many objects with similar size and mass to Pluto lurking around in its orbit. And until Pluto gets rid of these objects by perhaps, crashing into many of them and gains mass, it will remain a dwarf planet.
Image credit: NASA

Date with a Comet on Valentines Day!

The planned Valentine’s Day (Feb. 14, 2011) rendezvous between NASA’s Stardust-NExT mission and comet Tempel 1 inspired this chocolate-themed artist’s concept.

Read more about this mission and learn how you can watch the live webcasts of this event on NASA TV here. Also, check out this site to know Five Cool Facts  about NASA’s Stardust-NExT spacecraft as it prepares for a Valentine’s “date” with comet Tempel 1.

Image credit: NASA/JPL-Caltech


Successful Close Encounter with a ‘Space Peanut’: EPOXI’s flyby to Comet Hartley 2

credit: JPL/NASA

Just a few hours ago, NASA’s EPOXI mission spacecraft successfully flew past comet Hartley 2 at 6:59:47 a.m PDT (13:59:47 Universal Time) Thursday, Nov. 4.

The Deep Impact probe zoomed to within 435 miles (700 kilometers) of Hartley and  it took incredible images of the comet’s solid nucleus. The close encounter marked just the fifth time that a spacecraft has ever visited a comet.

Experts say initial images from the flyby provide new information about the comet’s volume and material spewing from its surface. The small but active comet is full of surprises, with spinning jets, geysers of cyanide gas, and a strange, irregularly-shaped core. The nucleus is only about 2.2 km (1.4 miles) across, so there’s not much mass in it, which means that it has weak gravity. In fact, the round ends of the nucleus are bumpy and rough, indicating material is loosely aggregated there.

EPOXI is an extended mission that uses the already in-flight Deep Impact spacecraft. Its encounter phase with Hartley 2 began at 1 p.m. PDT (4 p.m. EDT) on Nov. 3, when the spacecraft began to point its two imagers at the comet’s nucleus. Imaging of the nucleus began one hour later.

I watched the coverage of this event through an online live steaming available at NASA TV. I was updating my Facebook and Twitter account as I was waiting for updates and images of the closest approach. After more than an hour since the webcast began, the first images that were taken many hours before close encounter were  received. They depicted the comet nucleus as little more than a point of light, with the fuzzy coma surrounding it. I was saving screenshots every now and then as the images came in.

 

First snapshot of Comet Hartley! Notice the jets that were clearly visible streaming from the peanut-shaped comet nucleus. This shape is common in asteroids and comet nuclei, according to astronomers.

Moments later, a few of the close-approach images were finally shown. I was really amazed upon seeing its odd peanut-shaped body with an irregular and contoured surface. Images are available here and here. According to NASA EPOXI’s tweet, the 55 images taken about every 15 minutes were 256 x 256 subframes and the 5 close approach are full frames 1024 x 1024.

This image montage shows comet Hartley 2 as NASA’s EPOXI mission approached and flew under the comet. The images progress in time clockwise, starting at the top left.  This was taken by EPOXI’s Medium-Resolution Instrument. The sun is to the right.  Image credit: NASA/JPL-Caltech/UMD

A nice animation of the five close-approach images above 🙂 image credit: planetary.org

Those bright streamers of light are jets of gas shooting away from the comet, formed when frozen material on the comet surface gets heated by the Sun, expands, and shoots away.

 

This image shows many features across the comet's surface. The length of the comet is indicated. There are two obvious regions of jet activity associated with rough terrain. Image credit: NASA/JPL-Caltech/UMD

These are medium-resolution; hi-res ones will be coming soon.

Scientists are interested in comets because they’re icy leftovers from the formation of the solar system about 4.5 billion years ago. Studying them could provide clues to how Earth and the planets formed and evolved.

Congratulations to the EPOXI team for a successful commetary encounter  and for sending amazing  images! 😀

 

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Related links:

NASA EPOXI Flyby Reveals New Insights Into Comet Features

NASA Image Gallery

Hartley 2 compared to other comets, and in motion 3D

Jets are clearly visible streaming from the peanut-shaped comet nucleusJets are clearly visible streaming from the peanut-shaped comet nucleus


The Southern Taurids Meteor Shower plus some possible “Hartley-ids”

 

The constellations Cygnus (radiant of the Hartley-ids) and Taurus ( radiant of the Taurids) at 9:00 PM (UTC+8) Philippine sky

 

This week, watch out for the Southern Taurids Meteor Shower and some possible “Hartley-ids”!

The South Taurids are extremely long lasting (September 17 – November 27), but usually don’t offer a whole lot more than about 7 meteors per hour, even on the expected peak date of November 5. They are known  as “Halloween fireballs” because of its association with the meteors seen during Halloween and also for its  cool pumpkin-colored slow moving fireballs.

The greatest number of meteors generally fall around midnight to one in the morning, when the constellation Taurus the Bull rides high in the sky. Just remember that under any dark sky on any given day a person can see about five meteors if conditions are optimal. Southern Taurids meteor streams are groups of meteoroids originating from dust grains ejected from Comet 2P Encke.

Also on this week, there is a possibility of a “Hartley-id” shower coming from Comet 103P/Hartley – which has put on a good show for backyard astronomers last month — according to NASA’s Meteoroid Environment Office. If there is a Hartley-id shower, it would emanate from the constellation Cygnus the Swan, visible to observers in the northern hemisphere almost directly overhead after sunset in early November. NASA’s Epoxi mission will sweep past the Hartley 2 comet on Thursday (at about 2:00 PM UT) and take detailed measurements and images.

Lunar interference should not be a problem in observing these showers. Fortunately, the new moon falls on November 6, thus providing dark skies for a meteor watch.

* * *

More info…

The Taurids are actually divided into the Southern Taurids and the Northern Taurids (which will peak on November 13 this year).

Like the South Taurids, the Northern Taurids shower is long lasting (October 12 – December 2) but modest, and the peak number is forecast at about 7 meteors per hour.

==========================

sources:

SPACE.com

EarthSky.org


October 2010 Night Sky Guide

 

October is my favorite month when it comes to sky gazing 😀 My favorite constellation, Orion, starts become visible again during this time of the year.

Also, the famous Orionids – which I consider as one of the best meteor showers because of the high chance of “fireballs” lighting up the sky during this shower – make their appearance during this month.

Aside from these, the night sky is usually clear during October. Rain is infrequent and nights become longer and colder. As soon as early evening comes, the stars of different noticeable colors fill the sky like scattered jewels. Sagittarius, Scorpius and Corona Australis in the southwest, Bootes in the west, the royal family of Cepheus, Cassiopeia, and Andromeda with winged-horse Pegasus on the northeast, and the very prominent Summer Triangle up high, fill up the sky dome. As the evening wears on, more and more interesting constellations also show themselves like the Charioteer Auriga beside Taurus which contain the spectacular open star clusters, Hyades (the V-shaped one) and Pleiades (the rosary-like group).

So there. 🙂 I hope I have somewhat convinced you why I love this month. If you’re interested to do your own skygazing at your own backyards, I have compiled here a list of other special astronomical highlights for October 2010 as a guide in observing the night sky and to encourage more people to look up and appreciate the awesome sky display this season.

All dates are set for Philippine sky observers. (Note: PST is equivalent to UTC+8)

 

This month’s observing highlights:

Oct 7-8 : Draconids Meteor Shower (Expect a peak rate of 10 meteors per hour under clear, moonless conditions.)

The Draconids will start on October 6th and will continue until October 10th, when the Earth passes through the dust from the comet 21P/Giacobini-Zinner.

Although this particular meteor shower may not present a lot of meteor activity this year, it has been known to produce hundreds of meteors in an hour at times.

We are  in luck with the Draconids meteor shower this year for the new moon is scheduled for October 7, promising darkened conditions for easy observation. One of the best parts is that activity occurs earlier in the evening, so no one has to stay up till after midnight to catch a glimpse or obtain a full view, of the meteor shower.

Some people had reported to have seen 2 or more meteors during early this month in the northwestern direction around 6:30 – 7:00 PM.

Try to find these yellowish, slow-moving meteors around your area, too. Use the picture as a guide to locate the radiant point of the Draconid meteor shower which almost coincides with the head of the constellation Draco the Dragon, in the northern sky.

phtoto credit: meteorblog.com

 

Oct 6-9 : Comet Hartley 2 (officially designated 103P/Hartley) which is said to be the brightest comet this year, will be near the double cluster in Perseus.

Comet Hartley is expected to reach magnitude 5 during month. It is said to be large and diffuse, meaning its light is spread out over a wide area. You will definitely need a dark  sky – free of city lights – to see it. Also, when searching for the comet, remember to use averted vision. That’s the technique of looking to one side of the faint object you seek on the sky’s dome, instead of directly at it. Through binoculars, it should look like a smudge of light, like a faint, fuzzy green star against the dark sky background.

To find the comet near the the double cluster in Perseus, first find the constellation Cassiopeia the Queen, that is shaped like the letter M or W. Draw an imaginary line downward through the Navi (Gamma Cassiopeiae) and Ruchbah (Delta Cassiopeiae) just like the one shown below. It will point to the double cluster and Comet Hartley will be just within its vicinity.


Guide to finding Comet Hartley during early October

 

Comet Hartley 2’s path as shown against the background of constellations (click to enlarge view)

 

Oct 10 : Moon – Venus Conjunction

The Waxing Crescent Moon and Venus are both very close to the southwestern horizon at sunset.

Oct 11 : Moon near red Antares in Scorpius

Oct 20: Comet Hartley 2 will make its closest approach to Earth.

For a few days around October 20, the comet should be bright enough to view with the naked eye in the early morning sky. Look to the east just before sunrise.

This comet will be near the bright star Capella in the constellation Auriga. Capella is about 30 degrees above the northeastern horizon at 11 PM (PST) on this date.

Oct 20 : Waning Gibbous Moon – Jupiter Conjunction

These two will be less than 10 degrees apart. Check the eastern sky after sunset.

Oct 21-22 : Orionids Meteor Shower peaks

The Orionids is an average shower producing about 20 meteors per hour at their peak. Best viewing will be to the east after midnight. The radiant of the shower will be observed north of Betelgeuse, the brightest star in the constellation Orion, the Mighty Hunter.

Oct 26 : Moon in between Pleiades and the star Aldebaran in Taurus

 

* * * *

Planets

Mercury will be a “morning star” at the very beginning of the month, then will be too close to the Sun to observe for the rest of the month.

Venus sinks ever closer to the Sun as the month begins, making it very hard to observe in the Northern Hemisphere. Experienced observers with accurate setting circles or goto can follow it quite close to the Sun but should use extreme caution. The narrowing phase of Venus will be visible even in binoculars if you block the Sun with a rooftop or chimney. Inferior conjunction is on October 30.

Mars is pretty much lost in evening twilight.

Jupiter is just past opposition and visible most of the night, dominating the southern sky. It is in retrograde motion, so spends the first half of the month in the constellation Pisces, moving into Aquarius on October 15.

Saturn is in conjunction with the Sun on October 1, and reappears as a morning “star” late in the month. Its rings have now returned to their usual glory after being on edge for the last two years.

Uranus is in Pisces all month, and remains within a few degrees of Jupiter.

Neptune is visible most of the night in northeastern Capricornus.


* * * *

Moon Phases

October 7 – New Moon

October 15 – First Quarter Moon

October 23 – Full  Moon

The Full Moon of October is usually known as the Hunter’s Moon. This will spoil the Orionid meteors, which peak the night before.

October 30 – Last Quarter Moon

 

 

 

Clear skies and happy observing! 😀

 

 

 


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In astronomical terms…

+ Conjunction – two celestial bodies appear near one another in the sky

+ Radiant – (meteor shower) is the point in the sky, from which (to a planetary observer) meteors appear to originate. An observer might see such a meteor anywhere in the sky but the direction of motion, when traced back, will point to the radiant. A meteor that does not point back to the known radiant for a given shower is known as a sporadic and is not considered part of that shower.

 

sources: SPACE.com, EarthSky.org

October 2010’s night sky :)Oct 7 : New Moon
Oct 7-8 : Draconids Meteor Shower (Expect a peak rate of 10 meteors per hour under clear, moonless conditions.)
Oct
6-9 : Comet Hartley 2 near the double cluster in Perseus [to locate
this, draw an imaginary line downward through the Navi (Gamma
Cassiopeiae) and Ruchbah (Delta Cassiopeiae)]
Oct 10 : Waxing Crescent Moon-Venus Conjunction (check western sky a few minutes after sunset)
Oct 11 : Moon near red Antares
Oct
20 : Comet Hartley 2 will make its closest approach to Earth ( For a
few days around October 20, the comet should be bright enough to view
with the naked eye in the early morning sky. Look to the east just
before sunrise)
Oct 20 : Waning Gibbous Moon – Jupiter Conjunction (check Eastern sky)
Oct
21-22 : Orionids Meteor Shower Peak (The Orionids is an average shower
producing about 20 meteors per hour at their peak. Best viewing will be
to the east after midnight.)
Oct 26 : Moon in between Pleiades and the star Aldebaran
Clear skies!=====
*conjunction – two celestial bodies appear near one another in the sky

October 2010’s night sky 🙂

Oct 7 : New Moon

Oct 7-8 : Draconids Meteor Shower (Expect a peak rate of 10 meteors per hour under clear, moonless conditions.)

Oct

… 6-9 : Comet Hartley 2 near the double cluster in Perseus [to locate

this, draw an imaginary line downward through the Navi (Gamma

Cassiopeiae) and Ruchbah (Delta Cassiopeiae)]

Oct 10 : Waxing Crescent Moon-Venus Conjunction (check western sky a few minutes after sunset)

Oct 11 : Moon near red Antares

Oct

20 : Comet Hartley 2 will make its closest approach to Earth ( For a

few days around October 20, the comet should be bright enough to view

with the naked eye in the early morning sky. Look to the east just

before sunrise)

Oct 20 : Waning Gibbous Moon – Jupiter Conjunction (check Eastern sky)

Oct

21-22 : Orionids Meteor Shower Peak (The Orionids is an average shower

producing about 20 meteors per hour at their peak. Best viewing will be

to the east after midnight.)

Oct 26 : Moon in between Pleiades and the star Aldebaran

Clear skies!

=====

*conjunction – two celestial bodies appear near one another in the sky


Another Impact on Jupiter captured by an Amateur | 20 August 2010

A third Jupiter impact event in thirteen months has been captured by yet another diligent amateur observer.

Japanese amateur astronomer Masayuki Tachikawa caught the possible fireball event in a video at 18:22 UT on 20 August as a brief, two second, brightening near the north edge of Jupiter’s Northern Equatorial Belt. The flash, likely a small asteroid or comet burning up in Jupiter’s atmosphere, was later confirmed by another Japanese astronomer Aoki Kazu. Astronomers watching Jupiter for two rotations after the event found no trace of the impact.

The flash bears a striking resemblance to that observed by Anthony Wesley from Australia and Christopher Go from the Philippines on 3 June this year, and follows the report of a larger impact event, also observed by Wesley in July 2009, that left a dark impact scar in Jupiter’s atmosphere exactly fifteen years after the famous collision of comet Shoemaker Levy-9 with the gas giant.

The observations not only demonstrate the importance of amateur observations for monitoring our Solar System environment, but also the relative frequency of impact events still occurring in our planetary neighborhood today 😀

Below are the videos taken by Go and Tachikawa:


Lucky Friday the 13th! — Planet Parade and the 2010 Perseids

Many astronomy enthusiasts gathered last Friday, August 13 to observe the peak of the annual Perseids Meteor Shower as well as the beautiful display of planets after sunset.

My astronomy organization here in the Philippines, the UP Astronomical Society (UP AstroSoc), held a public observation for this event at the Sun Deck of PAGASA Astronomical Observatory in the University of the Philippines – Diliman. It was attended by around 30-40 guest who patiently waited for the Perseids despite the partly cloudy sky before midnight. The org’s telescopes were also set up so the attendees could view the planets Venus and Jupiter (with 4 of its moons!) which were visible during that night.

This observation was even featured in a news report of GMA’s Saksi, a local news program. Below is the video containing  interviews by some of the attendees:

 

Saksi: Astronomy enthusiasts await celestial alignment of 4 planets with Moon


Note: It was mentioned in the report that the planetary conjunction (planets appear near one another in the sky) is difficult to see without the use of telescopes. This is not true because seeing planetary groupings require a wider field of view (extent of the observable area) of the sky. Telescopes offer more details but have smaller field of view than our eyes.


I and two of my colleagues, Andre Obidos and Bea Banzuela, chose to observe from Marikina City. The skies were also cloudy there but we were still lucky enough to see and capture the ghostlike Moon with the planet Venus an hour after sunset in the west. Mars and Saturn however, were too dim to shine through the clouds.

We waited for the constellation Perseus (where the meteors would seem to radiate from) to rise around midnight but the sky was still full of clouds. We went out again around 3am but we saw nothing except for an overcast night sky with just a few bright stars like Altair, Vega and Deneb and the planet Jupiter which was nearly overhead. Following are some our images which were taken using Canon PowerShot SX 20:

Moon and Venus

Crescent Luna

Venus (15-sec exposure)

Reddish Moon

Other members of the organization went to different locations to help facilitate the other public observations of the event.

Below are photos taken by some UP AstroSoc members* during the observations.

members while waiting for the Perseids

UP AstroSoc members and guests at the PAGASA Sundeck while waiting for the Perseids

members posing beside one of the org's telescopes

a member peeks into the telescope to observe the planet Jupiter with its moons

Moon and Venus (viewed from Seven Suites Hotel in Antipolo)

members who went to Los Banos, Laguna posed beside the UPLB AstroSoc banner

Due to the coming of the rainy season here in the Philippines, having a clear night sky this month was almost impossible. Nonetheless, observers were still thankful that the clouds cleared up for even a short while, allowing them to see 4 or more of those beautiful bright streaks of light with the planets. 😀

According to the IMO measurements  the 2010 Perseid meteor shower was above normal with a peak activity of over 100 meteors per hour under optimal viewing conditions but not spectacular. In the coming nights the Perseids will still be visible, but with fewer and fewer meteors night by night.

==============

*Photo credits:

Ana Geronimo (in UP Diliman)

Regyn Avena (in UP Los Ba ños)

Zal Gerente (Seven Suites Hotel in Antipolo)

All photos were used with their permission.

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Rosetta Spacecraft’s Flyby of Asteroid Lutetia

On 10 July, ESA’s Rosetta spacecraft flew past 21 Lutetia, the largest asteroid ever visited by a satellite. This event was live webcasted here by ESA at 16:00 GMT.

Rosetta flew pass Lutetia at a relative speed of 54 000 km/hr, when both were located some 454 million km from Earth. As Lutetia is a major scientific target of Rosetta’s mission, most of the orbiter and lander instruments were kept on for flyby, studying the asteroid’s surface, dust environment, exosphere, magnetic field, mass and density.

The OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) camera system obtained visible-spectrum images before and at closest approach.

Rosetta launched in 2004, is on its way to a 2014 rendezvous with comet 67P/Churyumov-Gerasimenko.

For the complete time-line of events and more information visit ESA web page.

I just watched the webcast of this spectacular asteroid flyby and took a screenshot of one of the images that were sent back from Rosetta.

21 Asteroid Lutetia, OSIRIS image

I got too amazed while watching the live event that I forgot to make more screen-shots 😛 Meanwhile, here is a nice gif  of Asteroid Lutetia (courtesy of AsteroidWatch via Twitter)

Asteroid Lutetia (gif)

Can’t wait for the release of the hi-res photos by ESA 🙂

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UPDATES

The flyby has been a spectacular success with Rosetta performing faultlessly. Closest approach took place at 18:10 CEST, at a distance of 3162 km 🙂

Full report and hi-res images from ESA website can now be viewed.

Below are my additional screen-shots during the replay of the webcast and other hi-res images of the Asteroid Lutetia.

Lutetia at closest approach

Leaving Lutetia

with Saturn on the background, cool! 🙂

first images before approach

Almost approaching Lutetia

zoom in with grooves and craters

looking for more details

Though I won’t be able to view the July 2010 eclipse from here, these pictures had already made my day 🙂 Haha. Staying up until 7am in the morning was all worth it 🙂 Thank you Rosetta for bringing us nice images of Lutetia.

Before, asteroids seemed to be the least interesting objects to observe in the night sky. They can be hardly seen with the naked eye and they do not undergo phases like the moon or the inner planets. But now, I just realized that asteroids are cool space rocks too 🙂 Watching the live streaming has made me excited into viewing an asteroid closer for the first time. The hours I have spent waiting for the hi-res images to come out were truly fulfilling, thus seeing them made me really overwhelmed with joy 🙂

The universe is indeed a wonderful place 😀