Pan-STARRS discovers its first potentially hazardous asteroid

The Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) PS1 telescope has discovered an asteroid that will come within 4 million miles of Earth in mid-October. The object is about 150 feet in diameter and was discovered in images acquired on September 16, when it was about 20 million miles away.

esciencenews.com...

It seems like the dedicated anomaly finder is doing it's job. They can even size the asteroid!
I am not sure what we here on earth could do if it was projected to hit us, but I think Pan-Starrs is money well spent.

Wow, that means it's going to travel 16 million miles in a month. I'm no mathematician, so how many kilometers per hour is this big rock travelling? How far does Earth travel in a month at how many km/h?

reply to post by zenius


The Earth, travelling at ~106,800 km/hr, travels just under 77,000,000 kilometers in a 30-day month.

The asteroid (2010 ST3) is moving, too. The semimajor axis of its orbit (sort of the elliptical equivalent of a radius) is just over twice that of Earth's, and it is near perihelion, so it is catching up to us from behind. Closest approach will be on October 18, at ~16 times the distance from the Earth to the Moon.

Edited to add: It's brightness will be ~20th magnitude, so it will not be visible, except in large telescopes.

reply to post by Saint Exupery


Superb answer IMO.
The scope of the distance between Earth and Moon, really allowed me to understand how far away it would pass.

I have to ask you this question.
If a cold dark planet similar to a really large asteroid, 1000 miles across was spotted at the same distance headed our way. Would or could it travel at a similar speed as this asteroid?

reply to post by Saint Exupery


Thank you for your answer. Would you mind converting the asteroid speed to km/h also please?
Thanks in advance.

Originally posted by Tribble
I have to ask you this question.
If a cold dark planet similar to a really large asteroid, 1000 miles across was spotted at the same distance headed our way. Would or could it travel at a similar speed as this asteroid?

Yes. The difference in mass when compared to the Sun is trivial, so if such an object were in the same orbit as 2010 ST3, it would move at essentially the same velocity.

In terms of visibility, if we a 1000-mile object was in that orbit, and its surface was carbonaceous chondrite, which has about the same reflectivity as tar (2% - i.e. "dark"), it would still be one of the brightest things in the sky because of its close proximity to Earth (sunlight is *bright*). Only the Sun, Moon, Venus, Jupiter and Sirius would be brighter.

Originally posted by Tribble

The Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) PS1 telescope has discovered an asteroid that will come within 4 million miles of Earth in mid-October. The object is about 150 feet in diameter and was discovered in images acquired on September 16, when it was about 20 million miles away.

esciencenews.com...

It seems like the dedicated anomaly finder is doing it's job. They can even size the asteroid!
I am not sure what we here on earth could do if it was projected to hit us, but I think Pan-Starrs is money well spent.

If this asteroid did enter our atmosphere it would have the potential of being catastrophic over a localized area if it were to do a low air burst ( i think this happened a few years ago in africa) AND if it maintained its size. We usually have on average one or two fairly large asteroids enter our atmosphere yearly (15-50 ft in diameter). So this one would be quite a bit larger but probably not an extreme threat. I wonder what kind of damage a direct hit of an asteroid this size would cause? Would an air burst cause more damage?

edit: correction.

Originally posted by zenius
Wow, that means it's going to travel 16 million miles in a month. I'm no mathematician, so how many kilometers per hour is this big rock travelling? How far does Earth travel in a month at how many km/h?

Assume it's moving at the speed of 16 million miles/month.

In kilometres it's approximately 1,6 * 16 000 000 = 25 600 000 (in a month)

so in a day it would move about 25 600 000 km / 30 = 853 333 km

in one hour: 853 333 / 24 = 35 555,6 km/h

reply to post by GogoVicMorrow


I know very little about this asteroid stuff, but I did bookmark this info because I am concerned.

www.wired.com...

The rock, between 30 and 50 feet across, was not in danger of striking the planet and probably would have burned up in the atmosphere before hitting Earth’s surface, if it had headed our way. The asteroid, dubbed 2010 AL30 was first spotted and announced Monday. It is the closest encounter Earth will have with any known object until 2024. Read More www.wired.com...

Originally posted by Tribble
reply to post by GogoVicMorrow

 

I know very little about this asteroid stuff, but I did bookmark this info because I am concerned.

www.wired.com...

The rock, between 30 and 50 feet across, was not in danger of striking the planet and probably would have burned up in the atmosphere before hitting Earth’s surface, if it had headed our way. The asteroid, dubbed 2010 AL30 was first spotted and announced Monday. It is the closest encounter Earth will have with any known object until 2024. Read More www.wired.com...

Wait what is your concern? We have ones enter our atmosphere regularly that are the size of the wed one? Or did you mean concerned about Apophis? I've read about it for probably 10 years now.

reply to post by GogoVicMorrow

(15-50 ft in diameter). So this one would be quite a bit larger but probably not an extreme threat. I wonder what kind of damage a direct hit of an asteroid this size would cause?

I may have misunderstood your question, but I thought 150 diameter asteroid would sufficiently burn up into a non event, just as the article suggested. Am I that far off?

My concerns of being hit by an asteroid are only getting worse, the more I know about them. I read today that NASA's plan to detour a hazardous asteroid is to send a mission!

Originally posted by zenius
reply to post by Saint Exupery

 

Thank you for your answer. Would you mind converting the asteroid speed to km/h also please?
Thanks in advance.

Like I said above, the Earth's orbital velocity is ~106800 km/hr or 29.67 km/sec
At about the time 2010 ST3 crosses Earth's orbit, it's moving at ~135250 km/hr, or 37.55 km/sec, so it's overhauling us at ~28450 km/hr or ~7.88 km/sec.

If 2010 ST3 were on a collision course, as it got closer to Earth our gravity would accellerate it by 12 km/sec, Giving an impact velocity of almost 20 km/sec.

If we plug these numbers into the Earth Impact Effects Program, we find that 2010 ST3 would create a ~6 megaton airburst at ~9000m (30,000 feet), which in the same general range as the Tunguska blast of 1908.

I should clarify that the above calculation is for an object comprised of dense rock entering the atmosphere at 45 degrees.

Originally posted by Tribble
reply to post by GogoVicMorrow

 

(15-50 ft in diameter). So this one would be quite a bit larger but probably not an extreme threat. I wonder what kind of damage a direct hit of an asteroid this size would cause?

I may have misunderstood your question, but I thought 150 diameter asteroid would sufficiently burn up into a non event, just as the article suggested. Am I that far off?

My concerns of being hit by an asteroid are only getting worse, the more I know about them. I read today that NASA's plan to detour a hazardous asteroid is to send a mission!

edit on 28-9-2010 by Tribble because: detour

Yeah, 150 ft one most likely would, but if it didn't it wouldn't be a problem. With how many amatuer astronomers there are and satellites out on the sole mission of seeking these out, we have a fair chance of catching any giants. Comets are a little different because they come from deep outer space at great speeds so we don't get to watch them for years and years, but they are way less likely than asteroids. Don't get me wrong, earth impacts are very real, and a concern, but the problem is actively observed and in the scope of time one happening in our lifetime worrying over a small window.

reply to post by GogoVicMorrow


I did some reading on the Tunguska blast and the repeated probability was 300 years- Wiki (I crossed my fingers) The witness accounts were interesting. The constant sound of cannons firing I assume were either boulders returning to Earth or fragments exploding??

I then entered a 12 inch solid meteorite, hitting the earth (what is soil depth? I entered 30 feet)at 15 degrees- into the EIEProgram. If I understood it at all, it was an area of five square miles of total devastation. (thanks for the links Saint)

reply to post by Tribble

PS1 telescope has discovered an asteroid that will come within 4 million miles of Earth in mid-October

I don't understand, what's potentially hazardous about 4 million miles?

Didn't we recently have an undiscovered asteriod that came very close to us, I think it was like 158,000 miles away. Thats almost a 5th closer than the moon.

But still its good to see Pan-STARRS doing its job.

Peace.
ALS

reply to post by ALOSTSOUL


Good question. I think that it qualifies as hazardous because its orbit takes it closer to the Sun than the Earth's orbit, so technically it is an Earth-crosser. In fact, its orbit is inclined in such a way that, in three dimensions, its orbital path does not, in fact, intersect the Earth's orbital path (however, through perturbations, it might in the indefinite future).

reply to post by Saint Exupery


I see what your saying, its potentially hazardous because its future trajectory may bring it even closer or perhaps even impact with Earth.

Also:

Any sizable object that looks like it may come close to Earth within the next 50 years or so will be labeled "potentially hazardous" and carefully monitored.

I wonder what the cut off distance is for the label.

Peace.
ALS

For those of you who have Stellarium, try this:

1. In Windows Explorer, open the stellarium/data folder

B. Open the ssystem.ini file

III. Copy and paste the following into the ssystyem.ini file:

[2010 ST3]
name = 2010 ST3
parent = Sun
radius = .023
oblateness = 0.0
albedo = 0.05
lighting = true
orbit_visualization_period = 1325.46
halo = true
color = 1.0,1.0,1.0
tex_halo = star16x16.png
tex_map = nomap.png
coord_func = comet_orbit
orbit_Epoch = 2455457.5
orbit_MeanAnomaly = 343.4475050533811
orbit_SemiMajorAxis = 2.148390554460006
orbit_Eccentricity = 0.547588168688516
orbit_ArgOfPericenter = 241.7731499792991
orbit_AscendingNode = 171.5503238258748
orbit_Inclination = 3.944810355116661

iv. Save and close the ssystem.ini file.

e. Start the Stellarium software.

110. Press F3 and enter 2010 ST3.

Stellarium will show you the present position of asteroid 2010 ST3 and update it from now on. Enjoy!

reply to post by Tribble

did i not start this thread ??????