2000 SG344

Template:Short description

Template:Use dmy dates {{#invoke:infobox|infoboxTemplate | class = vcard | titleclass = fn org | title = Template:Mp | image = {{#invoke:InfoboxImage|InfoboxImage|image=Asteroid_2000_SG344.gif|upright={{#if:||1.1}}|alt=}} | caption = Template:Mp seen on 29 September 2000, as a dim streak in the center of the image, moving against the background field of stars | headerstyle = {{#if:#FFC2E0|background-color:#FFC2E0|background-color:#E0CCFF}} | labelstyle = max-width:{{#if:||11em}}; | autoheaders = y

| header1 = Discovery<ref name="MPEC" />

| header10 = {{#if:|Designations|Designations}}

| header20 = Orbital characteristics{{#ifeq:|yes| (barycentric)}}<ref name=jpldata />

| data21 = | data22 = {{#if:2020-May-31 (JD 2457400.5) |Epoch 2020-May-31 (JD 2457400.5)}} | data23 = {{#if:3 | Uncertainty parameter 3}} | label24 = Observation arc | data24 = 507 days (1.39 yr) | label25 = Earliest precovery date | data25 = | label26 = {{#switch:{{{apsis}}} |apsis|gee|barion|center|centre|(apsis)=Apo{{{apsis}}} |Ap{{#if:|{{{apsis}}}|helion}}}} | data26 = Template:Convert | label27 = Peri{{#if:|{{{apsis}}}|helion}} | data27 = Template:Convert | label28 = Peri{{#if:|{{{apsis}}}|apsis}} | data28 = | label29 = {{#switch:{{{apsis}}} |helion|astron=Ap{{{apsis}}} |Apo{{#if:|{{{apsis}}}|apsis}}}} | data29 = | label30 = Periastron | data30 = | label31 = Apoastron | data31 = | label32 = Template:Longitem | data32 = Template:Convert | label33 = Template:Longitem | data33 = | label34 = Eccentricity | data34 = 0.06696 | label35 = Template:Longitem | data35 = 0.97 yr (352.96 d) | label36 = Template:Longitem | data36 = | label37 = Template:Longitem | data37 = | label38 = Template:Longitem | data38 = 35.680° | label39 = Template:Longitem | data39 = 1.0198°/day | label40 = Inclination | data40 = 0.112202° | label41 = Template:Longitem | data41 = | label42 = Template:Longitem | data42 = 191.91° | label43 = Template:Longitem | data43 = | label44 = Template:Longitem | data44 = | label45 = Template:Longitem | data45 = 275.35° | label46 = Template:Nowrap | data46 = | label47 = Satellite of | data47 = | label48 = Group | data48 = | label49 = {{#switch: |yes|true=Satellites |Known satellites}} | data49 = | label50 = Star | data50 = | label51 = Earth MOID | data51 = Template:Convert | label52 = Mercury MOID | data52 = | label53 = Venus MOID | data53 = | label54 = Mars MOID | data54 = | label55 = Jupiter MOID | data55 = | label56 = Saturn MOID | data56 = | label57 = Uranus MOID | data57 = | label58 = Neptune MOID | data58 = | label59 = T_Jupiter | data59 =

| header60 = Proper orbital elements

| label61 = Template:Longitem | data61 = {{#if: |{{{p_semimajor}}} AU}} | label62 = Template:Longitem | data62 = | label63 = Template:Longitem | data63 = | label64 = Template:Longitem | data64 = {{#if: |{{{p_mean_motion}}} deg Template:\yr}} | label65 = Template:Longitem | data65 = {{#if:|{{#expr:360/1 round 5}} yr
({{#expr:365.25*360/1 round 3}} d) }} | label66 = Template:Longitem | data66 = {{#if:|{{{perihelion_rate}}} arcsec Template:\yr }} | label67 = Template:Longitem | data67 = {{#if:|{{{node_rate}}} arcsec Template:\yr}}

| header70 = Template:Anchor{{#if:yes| Physical characteristics|Physical characteristics}}

| label71 = Dimensions | data71 = | label72 = Template:Longitem | data72 = Template:Val (assumed)<ref name=nasa-risk-2000sg344/>
15–70 meters<ref name="NASA"/> | label73 = Template:Longitem | data73 = | label74 = Template:Longitem | data74 = | label75 = Template:Longitem | data75 = | label76 = Flattening | data76 = | label77 = Circumference | data77 = | label78 = Template:Longitem | data78 = | label79 = Volume | data79 = | label80 = Mass | data80 = 7.1Template:E kg (assumed)<ref name=nasa-risk-2000sg344/> | label81 = Template:Longitem | data81 = | label82 = Template:Longitem | data82 = | label83 = Template:Longitem | data83 = | label84 = Template:Longitem | data84 = | label85 = Template:Longitem | data85 = | label86 = Template:Longitem | data86 = | label87 = Template:Longitem | data87 = | label88 = Template:Longitem | data88 = | label89 = Template:Longitem | data89 = | label90 = Template:Longitem | data90 = | label91 = Template:Longitem | data91 = | label92 = Template:Longitem | data92 = | label93 = {{#if:yes |Template:Longitem |Albedo}} | data93 = | label94 = Temperature | data94 =

| data100 = {{#if:|

Surface temp.	min	mean	max
{{{temp_name1}}}
{{{temp_name2}}}
{{{temp_name3}}}
{{{temp_name4}}}

}}

| header110 = Atmosphere

| below = {{#if:||Template:Reflist }}

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Template:Mp is a small Aten asteroid first observed in 2000. It is assumed to have a diameter of approximately Template:Convert – or roughly twice that of the Chelyabinsk meteor – and an assumed mass of [[1 E10 kg|7.1Template:E kg]] (71,000 tonnes),<ref name=nasa-risk-2000sg344/> but the size is only known within about a factor 2. Template:As of, it is the largest object known to have a better than 1/1000 chance (0.1%) of impacting Earth and has the fifth highest cumulative Palermo scale rating at −2.77. The next good chance to observe the object will be in May 2028 when it passes Template:Convert from Earth.<ref name=jpldata/>

Because of its very Earth-like orbit and because it would have been near the Earth in 1971 (coinciding with the Apollo program), there was speculation that Template:Mp might not be an asteroid but a man-made object such as an S-IVB booster stage from a Saturn V rocket which would make it about 15 meters in diameter and much less massive.<ref name="NASA" /><ref name="Chodas-2001" /> (cf. J002E3, the S-IVB booster of Apollo 12 which was mistaken for an asteroid.)

Upcoming Earth approaches
Date & time	Nominal distance	uncertainty region (3-sigma)
2028-May-07 03:32 ± 4 minutes	Template:Val<ref name=jpldata/>	Template:Nowrap<ref name=Horizons2028/>
2030-Sep-22 22:36 ± 10 hours	Template:Val<ref name=jpldata/>	Template:Nowrap<ref name=Horizons2030/>

Possible impacts with EarthEdit

Until December 2004, it was considered to have the highest (though still very low) likelihood of any near-Earth object to impact Earth in the next 100 years. It is ranked a zero on the Torino scale of impact risk because of its small size (the scale is 0–10) and is listed on Sentry Risk Table.<ref name=nasa-risk-2000sg344 /><ref name=nasa-risk /> It was briefly surpassed in December 2004 by 99942 Apophis (which at the time was known only by its provisional designation Template:Mp). Smaller asteroids such as Template:Mpl and Template:Mpl have a greater chance of impacting Earth.

Based on 31 observations of Template:Mp made from May 1999 to October 2000, there is about a 1 in 360 chance that it will collide with Earth between 2069 and 2121.<ref name=nasa-risk-2000sg344/> The greatest chance of impact is on 16 September 2071 with a 1 in 1000 chance of impact. Assuming the object is a rocky asteroid and that it reaches Earth's surface without exploding in the atmosphere, the impact energy released would be an estimated 1.0 megatons of TNT, comparable to the Tunguska and Chelyabinsk events, which could create an impact crater approximately Template:Convert wide.

Virtual impactors<ref name=nasa-risk-2000sg344/>
Date	Impact probability (1 in)	JPL Horizons nominal geocentric distance (AU)	NEODyS nominal geocentric distance (AU)	uncertainty region (3-sigma)
2069-09-18	5 million	Template:Convert	Template:Convert<ref name="NEODyS2069"/>	Template:Nowrap
2070-09-17	4300	Template:Convert	Template:Convert	Template:Nowrap
2071-09-10	7100	Template:Convert	Template:Convert	Template:Nowrap
2071-09-16	1000	Template:Convert	Template:Convert	Template:Nowrap

Proposed NASA missionEdit

In 2008, NASA considered this asteroid as a possible target for a crewed mission (Artemis 2) using the Orion spacecraft, prior to a projected 2030 push to Mars.<ref name=guardian /><ref>Into the Beyond: A Crewed Mission to a Near-Earth Object – text slides</ref> Those plans were since abandoned. Template:Mp will be observable in May 2028 at an apparent magnitude of 19.<ref name="nhats"/>

ReferencesEdit

Template:Reflist

External linksEdit

NASA NEO Study home page
- Piloted Orion Flight Feasibility Study
Template:NeoDys
Template:ESA-SSA
Template:JPL small body

{{#invoke:Navbox|navbox}} Template:Authority control

2000 SG344

Contents

Possible impacts with EarthEdit

Proposed NASA missionEdit

ReferencesEdit

Further readingEdit

External linksEdit