This week’s apparition of asteroid 1994 PC1 offers observers a chance to see a space rock moving in real time.
In a slow moving universe, asteroids give us a rare chance to see things moving in real time. We have such a chance coming right up on the evening of Tuesday, January 18th, when 1.1-kilometer asteroid (7482) 1994 PC1 passes 1.23 million miles (1.98 million kilometers) from the Earth. This is about five times the distance from the Earth to the Moon, and just a shade over the distance to the anti-sunward Earth-Sun Lagrange 2 point, soon to be the home of the James Webb Space Telescope.
Incoming: The Earth-Moon system has company tonight.
The Asteroid: Near Earth Asteroid 2010 WC9 is back. Discovered by the Catalina Sky Survey outside Tucson, Arizona on November 30th, 2010, this asteroid was lost after a brief 10 day observation window and was not recovered until just earlier this month. About 71 meters in size, 2010 WC9 is one of the largest asteroids to pass us closer than the Earth-Moon distance.
2010 WC9 poses no threat to the Earth. About the size of the Statue of Liberty from the ground level to her crown, the asteroid is over three times bigger than the one that exploded over Chelyabinsk, Russia on the morning of February 15th, 2013.
The Pass: 2010 WC9 passes just 0.5 times the Earth-Moon distance (126,500 miles or 203,500 kilometers) on Tuesday, May 15th at 22:05 UT/6:05 PM EDT. That’s only roughly five times the distance of satellites in geosynchronous orbit. The asteroid is also a relative fast mover, whizzing by at over 12 kilometers per second. An Apollo-type asteroid, 2010 WC9 orbits the Sun once every 409 days, ranging from a perihelion of 0.78 astronomical units (AU) outside the orbit of Venus out to 1.38 AU, just inside the orbit of Mars. This is the closest passage of the asteroid by the Earth for this century.
Observing: This one grabbed our attention when it cropped up on the Space Weather page for close asteroid passes this past weekend: a large, fast mover passing close to the Earth is a true rarity. At closest approach, 2010 WC9 will be moving at 0.22 degrees (that’s 13 arcminutes, about half the span of a Full Moon) per minute through the constellation Pavo the Peacock shining at magnitude +10, making it a good telescopic object for observers based in South Africa as it heads over the South Pole.
North American and European observers get their best look at the asteroid tonight into early tomorrow morning while it’s still twice the distance of the Moon, shining at 13th magnitude and moving southward through the constellation Ophiuchus and across the ecliptic plane.
The best strategy to ambush the space rock is to simply aim a low power field of view at the right coordinates at the right time (see below), and watch. You should be able to see the asteroid moving slowly against the starry background, in real time.
Keep in mind, the charts we made here are geocentric, assuming you’re observing from the center of the Earth. Parallax comes into play on a close asteroid pass, and the Earth’s gravity will deflect 2010 WC9’s orbit considerably. Your best bet for generating a refined track for the asteroid is to use NASA JPL’s Horizons web interface to generate Right Ascension/Declination coordinates for the 2010 WC9 for your location.
How do you ‘lose an asteroid?” Often, an initial observation arc for a distant asteroid is too short to pin down a refined orbit. We have a blind spot sunward, for example, and fast moving asteroids can also be difficult to track across rich star fields and movement from one celestial hemisphere to the next. Recovery of 2010 WC9 earlier this month now gives us a solid seven year observation arc to peg its orbit down to a high accuracy.
Clouded out, or live in the wrong hemisphere? Slooh will carry an observing session for 2010 WC9 starting tonight at 24:00 UT/ 8:00 PM EDT. The Northholt Branch Observatories in London, England will also stream the pass live via Facebook tonight. Check their page for a start time.
There’s no word yet if Arecibo radar plans to ping 2010 WC9 over the coming days, but if they do, so expect to see an animation soon.
Don’t miss tonight’s passage of 2010 WC9 near the Earth, either in person or online.
Ready to hunt for low-flying space rocks? We’ve got an interesting pass of a Near Earth Asteroid (NEA) this upcoming U.S. Labor Day weekend, one that just slides over the +10th magnitude line into binocular range.
We’re talking about asteroid 3122 Florence, which passes 4.4 million miles from our fair planet (that’s 7 million kilometers, about 18 times the distance from Earth to the Moon) this Friday on September 1st at 12:06 Universal Time (UT)/ 8:06 AM Eastern Daylight Saving Time (EDT).
Universe Todayran an article on the close pass about a week ago. Now, we’d like to show you how to see this asteroid as it glides by.
Ordinarily, a four million mile pass (about 4.7% of an astronomical unit, just under the criterion to make 3122 Florence a Near Earth Object) isn’t enough to grab our attention. Lots of asteroids pass closer weekly, and 3122 Florence is certainly no danger to the Earth this or any week in the near future. What makes this asteroid an attractive target is its size: NASA’s NEOWISE and Spitzer infrared telescope missions estimate that 3122 Florence is about 2.7 miles (4.4 kilometers) in diameter, a pretty good-sized chunk of rock as near Earth asteroids go.
The last large asteroid with a similar close approach was 4179 Toutatis, which passed just under four lunar distances (a little under a million miles) from the Earth on September 29th, 2004.
Asteroid 3122 Florence (1981 ET3) was discovered by prolific asteroid hunter Schelte J. Bus from Siding Spring observatory in Australia on the night of March 2nd, 1981. Named after social reformer and founder of modern nursing Florence Nightingale, this weekend’s pass is the closest 3122 Florence gets to Earth over a 600 year plus span, running from 1890 (well before its discovery) out past 2500 AD.
3122 Florence has an inclined orbit, tilted 22 degrees in respect to the ecliptic plane. Orbiting the Sun once every 859 days, 3122 Florence travels from around 1 to 2.5 AUs from the Sun, making it an Amor class asteroid which journeys beyond the orbit of Mars and approaches but doesn’t pass interior to the orbit of the Earth.
This week’s pass sees 3122 Florence rapidly vaulting up from the southern to northern hemisphere.
This apparition culminates on Friday, September 1st, at 12:06 UT as the asteroid crosses the along the border of the constellations Equuleus and Delphinus at closest approach, reaching +9th magnitude. 3122 Florence will be moving at 20′ per hour (that’s about 2/3rds the diameter of the Full Moon) at closest approach, fast enough that you’ll notice its motion against the background stars in a low power field of view after about 10 minutes or so.
3122 Florence crosses through the constellations Piscis Austrinus, Capricornus, Aquarius, Equuleus and Delphinus this week. Keep in mind, the Moon is headed towards Full next week on September 6th, making the next few evenings a good time to track this fleeting space rock down.
Finding 3122 Florence
3122 Florence races across the ecliptic northward on the night of August 29th and also crosses the celestial equator on September 1st
Tonight is also a good time to track down 3122 Florence, as it passes just 16′ from +3.8 magnitude star Zeta Capricorni. It also threads its way through the tiny the diamond-shaped asterism of Delphinus the Dolphin just over week after its closest pass on the evening of Saturday, September 9th.
Currently, 3122 Florence is 45 degrees above the southern horizon around local midnight for observers based along 30 degrees north latitude. The best view during Friday’s pass is from the Pacific Rim, including Australia, New Zealand and surrounding regions at closest approach.
North American viewers will get a good view at local midnight just about eight hours prior to closest approach on the night of August 31st/September 1st, about 60 degrees above the southern horizon. The next good views occur the following evening about 16 hours after closest approach, as the asteroid is receding but 10 degrees higher above the southern horizon.
A series short wide field exposures over about an hour revealing stars down to +10 magnitude should reveal the motion of 3122 Florence against the starry background. A good visual alternative is to sketch the suspect star field about 10 minutes apart, carefully looking for a ‘star’ that has moved during the intervening time.
JPL Horizons is a good place to generate accurate right ascension and declination coordinates for 3122 Florence to aid you in your quest. This one is distant enough to simple geocentric coordinates should suffice, and observer parallax shouldn’t shift the position of the asteroid significantly.
Clouded out? The good folks over at the Virtual Telescope Project will be featuring 3122 Florence during a live webcast starting on Thursday, August 31st at 19:30 UT/3:30 PM EDT.
We can be thankful that 3122 Florence isn’t headed Earthward, as it’s perhaps about half the size of the 10-15 kilometer diameter Chicxulub impactor that hit the Yucatan 65 million years ago, causing a very bad day for the dinosaurs. Plus, it would just be weird if an asteroid named after humanitarian Florence Nightingale caused the extinction of humanity…
And this is a great pre-show for a smaller and closer anticipated asteroid pass coming up in a few short weeks, as 2012 TC4 buzzes the Earth on October 12th, 2017.
Good luck in your quest to find 3122 Florence… let us know what you see!
It’s a shooting gallery out there. The spattered face of Earth’s Moon and large impact sites such as Meteor Crater outside of Flagstaff, Arizona remind us that we still inhabit a dangerous neck of the solar neighborhood. But despite the inevitable cries proclaiming the “End of the World of the Week” this coming weekend, humanity can breathe a collective sigh of relief next Wednesday on April 19th, when asteroid 2014 JO25 passes safely by the Earth.
To be sure, lots of smaller space rocks pass by the Earth closer than the Moon (that’s an average of 240,000 miles distant) on a monthly basis. Take for example 4-meter asteroid 2017 GM, which passed just 16,000 kilometers distant on April 4th. What makes 2014 JO25 special is its size: measurements from NASA’s NEOWISE mission suggest that 2014 JO25 is about 2,000 feet (650 meters) along its longest axis, about twice the length of a Nimitz-class aircraft carrier. 2014 JO25 is passing 1.1 million miles (1.8 million kilometers) or 4.6 times the Earth-Moon distance on Wednesday, the closest large asteroid pass since 5-km Toutatis in September, 2004. The next predicted large asteroid pass near Earth is 1999 AN10, set to pass 1 LD (lunar distance) from the Earth in 2027.
This is also the closest passage of 2014 JO25 near the Earth for a 900 year span.
Discovered on May 5th, 2014 by the Catalina Sky survey, asteroid 2014 JO25 orbits the Sun once every three years, taking it from a perihelion of 0.237 AU (interior to Mercury’s orbit) out to an aphelion of 3.9 distant in the asteroid belt, interior to Jupiter’s orbit.
Finding 2014 JO25 at its Closest Approach
With an estimated albedo (surface brightness) about twice that the lunar surface, 2014 JO25 will reach magnitude +10 to +11 on closest approach on Wednesday. Currently low in the dawn sky in the Square of Pegasus asterism, asteroid 2014 JO25 passed perihelion sunward as seen from the Earth at 1.015 Astronomical Units (AU) distant on March 11th. At its closest to the Earth on April 19th at 12:24 Universal Time (UT)/6:24 AM EDT, asteroid 2014 JO25 will skim the jagged Draco-Ursa Minor border below the bowl of the Little Dipper, moving at a whopping three degrees per hour. Sitting just 25 degrees from the north celestial pole on closest approach, catching sight of 2014 JO25 at favors western North America and northeastern Asia, though the eastern half of North America and Europe have a shot at the asteroid a few hours prior to closest approach in the early morning hours of April 19th. North American viewers get another shot at catching the fleeting asteroid later the same evening 13 hours after closest approach as the asteroid sails through the galaxy-rich constellation Coma Berenices.
At +11th magnitude, you’ll need a telescope of at least 6” aperture or larger and a good star chart to nab 2014 JO25 as it glides against the starry background. Fellow Universe Today contributor Bob King has some great star charts of the pass over at Sky & Telescope. The Moon will be at Last Quarter phase on the morning of the 19th, providing moderate light pollution.
And if you’re out hunting for asteroids on the coming mornings, there are currently two bright binocular comets in the dawn sky to keep you company: Comet C/2017 E4 Lovejoy in the constellation Andromeda and Comet C/2015 ER61 PanSTARRS in Aquarius. Both are currently performing above expectations at about magnitude +7.
“What if” an asteroid the size of 2014 JO25 hit the Earth? Well, the Chelyabinsk meteor was an estimated 20 meters in size; the impactor that formed Meteor Crater in Arizona was about 50 meters in diameter. The Chicxulub event off the Yucatan peninsula 66 million years ago was an estimated 10 kilometer-sized impactor well over ten orders of magnitude bigger than 2014 JO25. While the impact of a 600 meter asteroid would be a noteworthy event and a bad day locally, it would pale in comparison to an extinction level event.
All something to consider, as you watch the faint dot of asteroid 2014 JO25 pass harmlessly by the Earth and through the news cycle for the coming week.
BREAKING- No sooner than the cyber-ink was dry on this post than we got notice of another 10-metre NEO asteroid 2014 EC passing Earth at just under 0.2 times the Earth-Moon distance – less than 64,000 kilometres – on Thursday, March 6th at 21:18 UT/4:18 PM EST. And the Virtual Telescope will be carrying this passage live as well on March 6th starting at 19:00 UT/2:00 PM EST. Bring in on, universe!
The Earth-Moon system gets a close shave on the night of Wednesday, March 5th 2014 when Near Earth Object (NEO) asteroid 2014 DX110 passes our fair planet at 216,000 miles or about 345,600 distant at around 21:06 Universal Time (UT)/ 4:06 PM EST.
About 30 metres in diameter, 2014 DX110 was discovered by the Pan-STARRS 1 survey on February 28th, and its orbit was initially refined using follow up observations made by the Great Shefford Observatory in West Berkshire, England.
And although the asteroid is no threat to Earth or the Moon – it makes a pass 232,800 miles from our natural satellite one hour and 22 minutes after its closest passage from the Earth – the asteroid is currently listed on NASA’s risk page for a 1 in 10,000,000 chance of impact with Earth on March 4th, 2046.
Of course, additional observations usually lower this remote possibility even further in the case of most newly discovered near Earth asteroids. Visually, 2014 DX110 isn’t expected to brighten above +15th magnitude as it glides northward through the constellation of Camelopardalis at closest approach Wednesday night.
But the good news is, you can catch the passage of 2014 through the Earth-Moon system Wednesday night courtesy of our friends at the Virtual Telescope Project:
The webcast of the event is expected to go live at 20:30 UT, and will include live commentary.
Its been a busy last few weeks in terms of asteroid flybys, including a passage of Amor NEO asteroid 2014 DU110 earlier today at 15:54 UT/10:54 AM EST at 0.14 A.U.s or just over 20 million kilometres distant. And the folks at the Virtual Telescope Project will be covering another asteroid flyby on Sunday, March 9th starting at 23:00 UT/6:00 PM EST to track the 180 meter asteroid 2014 CU13. This large Apollo NEO is projected to pass 8 lunar distances or over 3 million kilometres away from the Earth on March 11th at 9:05 UT/4:05 AM EST.
It should be easy to pick out the motion of 2014 DX110 moving against the starry background at closest approach in real time. 2014 DX110 is an Apollo-class asteroid, and has an orbital period of 1192 days or about 3.26 years. It also has a fairly shallow inclined orbit relative to the ecliptic traced out by Earth’s path around the Sun, with a tilt of just over 5.7 degrees. This means that 2014 DX110 is approaching the Earth from just southward and behind it in its orbit around the Sun before crossing just inside of our orbit and northward of the ecliptic plane.
The discovery of asteroid 2014 DX110 was announced by the Minor Planet Center on Sunday, March 2nd in electronic circular 2014-E22. The orbit of 2014 DX110 takes it just interior of Earth’s at a perihelion of 0.83 A.U.s from the Sun and out to an aphelion of 3.6 A.U.s into the realm of the asteroid belt between Mars and Jupiter.
Generally speaking, asteroids passing interior to the Moon’s orbit grab our attention for further scrutiny. Looking back through the European Space Agency’s Near-Earth Objects Dynamics Site, asteroid 2014 DX110 also made an undocumented close passage of Earth on March 17th, 1998 at a minimum possible miss distance of 102,300 miles/163,680 kilometres distant, and a similar passage March 22nd, 1982. 2014 DX110 passed sufficiently close enough to Earth on these passages to alter its orbit so that it now returns to our terrestrial neighborhood every 13 odd years during the span of the 21st century. 2014 DX110 will be moving at a velocity of 14.8 kilometres per second relative to Earth on closest approach Wednesday night and will be inside the Earth’s Hill sphere of gravitational influence from March 4th to March 7th, though of course, it’s moving much too fast for capture.
2014 DX110 will be interior of the Moon’s orbit from 18:06 UT/1:06 PM EST on March 5th until 00:07 UT March 6th (7:07 PM EST on the night of March 5th). The large size – about the size of an office block – and the nature of its orbit, coupled with its relatively large velocity relative to the Earth rule out any potential for 2014 DX110 being space junk in solar orbit returning to Earth’s vicinity, though such objects from the Apollo missions and the Chinese Chang’e-2 Moon mission have been recovered as Earth asteroids before.
Such an impact risk, however remote, merits further study to refine the orbit of this potentially hazardous space rock. Surveys such as PanSTARRS, the Catalina Sky Survey and the B612 Foundation’s asteroid hunting Sentinel space telescope slated for launch as early as 2017 are working to identify dangerous space rocks. The next and more difficult step will be mitigation and working to nudge these asteroids out of harm’s way, hopefully years in advance.
But you can breathe a sigh of relief Wednesday night as asteroid 2014 DX110 passes us at a safe distance. Thanks to Gianluca Masi at the Virtual Telescope Project for bringing this one to our attention!
Can’t find asteroid 2010 QW1 in the Minor Planet Database? No, the “Men in Black” didn’t secretly remove this Earth-orbiting asteroid from the listing… but recent top-notch detective work by astronomers did.
The mystery of this object all started back on August 23rd of this year, when the PanSTARRS sky survey based on the summit of Haleakala on the island of Maui in Hawai’i spotted an asteroid that was given the provisional designation of 2013 QW1.
The object was in a wide-ranging orbit around the Earth, leading astronomers to wonder if it was a naturally captured asteroid or perhaps space debris from a previous launch. Either solution to the dilemma would be fascinating. Our large Moon keeps the Earth pretty well swept clear of debris, though a “second Moon,” however small, would be an interesting find. And if 2013 QW1 were to prove artificial, it just might be a piece of history.
The European Space Agency’s NEO Coordination Centre decided to take up the challenge. A call went out to track and observe the 2013 QW1, and a team led by Elisabetta Dotto of INAF-Observatorio di Roma & Maria Barucci & Davide Perna of the Observatoire de Paris managed to get time on the Italian Telescopio Nazaionale Galileo based at La Palma to obtain a spectrum of the object.
“It was a bit of a challenge, because the object was moving fast with respect to a typical NEO,” said Dr. Perna in a recent ESA press release.
The team used an instrument known as DOLORES to make the crucial measurements. DOLORES stands for the Device Optimized for LOw RESolution. The spectrum obtained in the early morning hours of August 25th shows something much brighter than your typical asteroid, but is characteristic of a painted metallic object.
And thus, 2013 QW1 was removed from the ledger of NEO asteroids maintained by the IAU Minor Planet Center (MPEC). And the leading suspect? The third stage booster of a Chinese Long March 3C rocket that launched the Chang’e 2 spacecraft from Xichang, China on October 1st, 2010.
Chang’e-2 entered lunar orbit 8 days after launch, and departed on June 8th of the following year after studying and mapping the Moon. Chang’e-2 then went on to become the first spacecraft to directly reach the L2 Lagrange point 1.5 million kilometres beyond Earth from lunar orbit. The spacecraft also made the first flyby of NEO asteroid 4179 Toutatis on December 13th of last year. The probe is estimated to continue functioning into 2014, and will be used to hone China’s ability to track objects in deep space.
The NORAD tracking identification assigned to the 3rd stage booster that launched Chan’ge-2 is 2010-50B.
This sort of discovery is not without precedent.
On September 3rd, 2002, amateur astronomer Bill Yeung discovered an asteroid tentatively designated J002E3. Subsequent studies revealed that the asteroid had a spectrum consistent with that of titanium oxide paint, a decidedly unasteroid-like coating for a space rock to sport. This was, however, a common veneer in use during the Apollo era, and it is now known that J002E3 is the S-IVB third stage booster that launched the second mission to land men on the Moon on November 14th, 1969. Unlike other boosters, such as the one that launched Apollo 14, the Apollo 12 3rd stage did not impact the Moon as part of seismic experiments. After a brief period as a “pseudo-moon” of the Earth, J002E3 was kicked out into solar orbit in June 2003 and may return to our neighborhood once again in the 2040s.
NASA’s Lunar Reconnaissance Orbiter has documented the lunar crash sites of these historic boosters. It’s of note that the Apollo 10 Lunar Module Snoopy remains discarded out in solar orbit as well, having been used as a dress rehearsal for the historic Apollo 11 landing. Apollo 10 never landed on the Moon. Efforts have been made by UK astronomer Nick Howes to recover it as well.
And there are more relics of the Space Age awaiting discovery. One of the first things we always check in the case of a pass by a newly discovered NEO closer than the Moon to the Earth is its history, to see if it matches up with any launches headed out beyond Earth orbit in the past.
And the upcoming Mars launches of MAVEN and India’s Mars Orbiter Mission in October & November will be the first to depart Earth orbit since 2011. These will give future generations of asteroid hunters new human-made space hardware to ponder.
The B612 Foundation’s asteroid-hunting Sentinel Space Telescope will also “up the game,” scouting for asteroids from a vantage point interior to the Earth’s orbit. Sentinel is slated for launch in 2016 atop a SpaceX Falcon 9 rocket.
And no, the fabled “Black Knight” satellite of UFO conspiracy buffs’ dreams is nowhere to be found.
What other fascinating relics of the Space Age lie are out there in the solar system, waiting to tell their tale?