Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Use NASA/JPL’s Eyes on Asteroids for a visual overview, the Small-Body Database (SBDB) to look up an asteroid’s orbital elements, and Horizons to calculate where a body will appear over a specified time span. These tools answer different questions: a displayed orbit is useful for orientation, while numerical work requires the right data product and its epoch, coordinate frame, and update status.
Choose the right NASA/JPL tool
| Tool | Best for | What it provides | Important qualification |
|---|---|---|---|
| Eyes on Asteroids | Getting a visual overview of asteroids, comets, close approaches, and missions | Interactive visualization of thousands of small bodies and missions past, present, and future | It is an orientation tool; use SBDB or Horizons when you need specific numerical data. The visualization uses CNEOS data. [c001] |
| SBDB Lookup | Identifying a small body and inspecting its orbit and related information | Orbital elements, uncertainties where available, orbit diagrams, and other object details | The built-in orbit viewer uses two-body methods and is not intended for accurate long-term trajectories or planetary encounter circumstances. [c005] |
| Horizons | Calculating time-dependent positions or generating other numerical output | Ephemerides, orbital elements, and SPK trajectory files | Results depend on the selected target, observer or reference center, dates, step size, and output settings. Spacecraft trajectories may be outdated. [c002] [c003] |
For a general explanation of how orbit descriptions and ephemerides differ, see JPL’s orbits and ephemerides guide. [c008]
As an Amazon Associate I earn from qualifying purchases.
Track a mission or asteroid visually
- Open Eyes on Asteroids and select an object or mission in the visualization.
- Use the display to understand the broad relationship between the object, its orbit, close approaches, and mission trajectories. The tool also offers a view of the next five close approaches. [c001]
- For a specific orbit value, time-stamped position, or precision-sensitive question, continue to SBDB or Horizons rather than treating the visual display as a numerical forecast.
Eyes on Asteroids draws on data from CNEOS, the Center for Near-Earth Object Studies, which computes high-precision orbits for near-Earth objects. Its purpose is to make the overall picture easy to explore, not to replace the data services used for a defined calculation. [c001]
The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Look up the object unambiguously in SBDB
- Open SBDB Lookup.
- Search using an IAU number, formal designation, name, or JPL SPK-ID. Prefer a number or formal designation when a name might refer to more than one object. [c005]
- Inspect the available orbital elements and uncertainties along with the object’s other record details, such as physical parameters, close-approach information, radar astrometry, discovery circumstances, and alternate designations. Availability varies by object. [c005]
Do not use SBDB’s orbit viewer to determine accurate long-term trajectories or planetary encounter circumstances: JPL says it uses two-body methods. Use Horizons for those calculations. [c005]
#1 Best Overall
- 【Excellent Optics】Astronomical telescope features 80mm aperture 600mm(f/6.7) focal length-The big aperture can capture more light; high transmission multi-fully coated optical lens can improve light transmittance, reduce the reflection of light. It will bring you more bright and clear images.
- 【Portable & Stable】Our refractor telescope has a backbag, an adjustable aluminum tripod and an upgraded phone adapter. All accessories can be packed into the bag, which is convenient for you to carry and storage for traveling. The tripod is stable and the height can adjust from 17.7" to 52", which is suitable for adults and kids. With the phone adapter, you can take amazing photos through your phone.
- 【Easy to Operate】 This telescope is easy to assemble even for astronomy beginners and kids. You can set up easily with the detail installation manual and video. No tools are required. It’s a great astronomy gift telescope for adults, astronomy enthusiasts, beginners and kids 8-12.
- 【Optimum Magnification】Our telescope for kids and adults is equipped with two replaceable excellent-quality eyepiecesa (20mm and 9mm) for 30X and 66X magnification. A moon filter transmits only 13 percent of the incoming light and improving contrast. Also with 5x24 finderscope, you can locate objects easily. A great option for astronomy lovers to explore the moon, Saturn and Jupiter.
- 【Satisfaction Service】We provide 3 years satisfaction service. If you have any questions about the product and service, please feel free to contact us to get 24-hour technical support from our expert team. Whether observing moon or viewing planets, our telescope can meet your all needs. It’s a great telescope for adults & 8-12 kids & astronomy beginners.
Know whether you need elements, an ephemeris, or an SPK
Orbital elements describe an orbit at an epoch
Elements are a compact description of orbital geometry or state at a specified time, relative to a selected body or barycenter. They are not timeless constants. Horizons can return an osculating-elements set, meaning an instantaneous representation for the selected epoch and reference. [c003]
Ephemerides give values over time
An ephemeris provides quantities such as sky position and rates across a time interval for a specified observing location. Use one when the question is “Where will this object appear, and when?” rather than “What elements describe its orbit?” [c003]
Rank #2
- Superior Optics: 400mm(f/5.7) focal length and 70mm aperture, fully coated optics glass lens with high transmission coatings creates stunning images and protect your eyes. Perfect full positive telescope for astronomers to explore stars and moon.
- Magnification: Come with two replaceable eyepieces and one 3x Barlow lens.3x Barlow lens trebles the magnifying power of each eyepiece. 5x24 finder scope with mounting bracket and cross-hair lines inside make locating objects easily.
- Wireless Remote: This refractor telescope includes one smart phone adapter and one Wireless camera remote to explore the nature of the world easily through the screen and take amazing celestial images.
- Adjustable Tripod: This telescope allows for many different viewing positions with a adjustable aluminum alloy tripod and a carry bag, the telescope and tripod can fit inside the bag for easy traveling and storage.
- Satisfaction: Buy with confidence from a leading manufacturer.
SPK files are for downstream software
Horizons can generate SPK files, a binary trajectory format for use in other software workflows. Choose this output when the next step requires a trajectory file rather than a human-readable table. [c002] [c003]
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsRead orbital elements with their context
Depending on the selected output, Horizons may list epoch, eccentricity, periapsis distance, inclination, longitude of ascending node, argument of periapsis, mean anomaly, true anomaly, semimajor axis, and period. Read each value together with the metadata that makes it interpretable:
Rank #3
- SMARTPHONE-POWERED SKY TOUR: No experience needed! Just dock your phone, launch the StarSense Explorer app, and follow the on-screen arrows to locate stars, planets, nebulae, and more.
- PATENTED STARSENSE TECHNOLOGY: Unlike other astronomy apps, StarSense Explorer uses sky recognition technology to turn your phone into a celestial navigation system, analyzing star patterns overhead to pinpoint your telescope’s position.
- TONIGHT’S BEST TARGETS, INSTANTLY: The app generates a curated list of the top objects to see based on your time and location. See planets, bright nebulae, galaxies, and star clusters from the city—and even more from dark skies.
- SIMPLE SETUP, SMOOTH TRACKING: Features a manual altazimuth mount with altitude slow motion adjustment with a sliding rod. Follow the on-screen arrows to your target; when the bullseye turns green, you can view it clearly through the eyepiece.
- 114MM REFLECTOR WITH IMPRESSIVE VIEWS: The 4.5" Newtonian reflector with high-reflectivity coatings delivers sharp, vivid views of the Moon, planets like Jupiter and Saturn, and deep-sky favorites like the Orion Nebula and Andromeda Galaxy.
- Epoch: the time the element set represents.
- Reference: the selected body or barycenter and reference plane or frame.
- Coordinate system and units: the conventions used for the output.
- Uncertainty: the SBDB record includes orbital-element uncertainties where available; retain them when using the values for observation, hazard, or mission planning. [c002] [c003]
Orbit solutions are fitted to astrometric observations using debiasing, weighting, perturbation models, and numerical methods. As observations accumulate, the solution can improve, so a quoted value should be tied to the specific solution or retrieval date rather than presented as permanent. [c006]
Request Horizons output deliberately
Horizons can be used interactively or through its API. The API supports observer ephemerides, orbital elements, and SPK output; requests need a valid target command and settings appropriate to the question. [c003]
Rank #4
- Superior Optics: Dianfan astronomy telescope features a focal length of 800 mm and a fully coated 90 mm objective lens. The large aperture gathers more light for brighter, clearer views, high-transmission coatings enhance contrast and color for sharp, vivid images for an enjoyable stargazing experience
- Powerful Magnification: With two eyepieces and a 3× Barlow lens, this telescope offers 32×–240× magnification. It allows you to observe craters and lunar seas on the surface of the Moon. With the 45° zenith mirror, images are upright and correctly oriented for terrestrial viewing, making distant targets details easier to observe. The telescope is ideal for beginners and astronomy enthusiasts
- Quick Setup & Beginner-Friendly: User-friendly design with clear instructions makes assembly simple—ready in about 15 minutes. Smooth focusing helps you quickly locate targets. Perfect for families to enjoy stargazing and explore the night sky together
- Portable & Versatile: Lightweight design with a sturdy stainless steel tripod ensures stable, steady viewing. Easy to carry in the included bag, making it perfect for travel and outdoor adventures. Suitable for stargazing, birdwatching, wildlife observation, and exploring cityscapes
- Professional Astronomical Telescope: The Dianfan 90x800 telescope combines quality , functionality and reliability. It delivers high-resolution views that bring the universe closer. Designed for adults high powered, it inspires interest in astronomy and science while encouraging exploration of the starry sky
- Choose the target carefully, using an unambiguous designation or identifier.
- Select the observer or center that matches the question: an apparent sky position depends on where it is observed from.
- Set the start and end times and the step size for a time series.
- Select only the output quantities you need, then confirm the reported units and coordinate conventions.
- For API use, follow JPL’s URL-encoding requirements and the documented parameter names rather than assembling a request by guesswork. [c003]
These choices define what the result means. An ephemeris for one observer and interval is not interchangeable with an orbital-element set or a view from another location.
Check spacecraft trajectory freshness before relying on it
Asteroid orbit solutions and spacecraft trajectories do not necessarily update on the same schedule. The Horizons manual warns that externally produced spacecraft trajectories may lag planning changes or maneuvers. In the spacecraft data sheet, check the revision date in the upper-left corner and read the comments for mission-status information. [c003]
Best Value
- BRIGHT, SHARP VIEWS ANYWHERE: Unlike many beginner telescopes, this quality refractor features fully coated glass lenses and a 70mm aperture for crisp, clear views of the Moon, planets, and daytime scenery—all in a lightweight, travel-ready design.
- PERFECT FIRST TELESCOPE FOR BEGINNERS: Designed for adults and kids to enjoy together, this beginner-friendly telescope sets up in minutes and delivers rewarding views with no prior experience required.
- EASY NO-TOOL SETUP: No complicated assembly or tools needed. The full-height tripod and telescope tube set up in seconds and pack neatly into the included backpack—so you’re always ready to observe on the go.
- DUAL EYEPIECES FOR VERSATILE VIEWS: Includes 20mm and 10mm eyepieces for wide and close-up views of celestial and terrestrial targets. Spot craters on the Moon at night or wildlife during the day.
- BONUS BACKPACK AND SOFTWARE: Includes a padded backpack with room for accessories, a finderscope, star diagonal, eyepieces, and a free download of Starry Night software to help you identify celestial objects and plan your next stargazing session.
The manual states: “Always check the revision date in the upper left corner of the Horizons spacecraft data-sheet to determine the last time the spacecrafts’ trajectory was updated, and read the data-sheet comments for mission status information.” For high-precision interplanetary applications, JPL advises contacting Solar System Dynamics if the revision status is uncertain. Do not infer current navigation status from an old trajectory alone. [c003]
Check mission targets and close-approach context
JPL’s selected small-body mission-target table lists target body, mission type, arrival, mission name, launch, and status, with links to SBDB and mission pages where available. Its entries change over time, so consult the live table for current status and dates rather than relying on a saved arrival date. [c004]
For context on risk terminology, NASA/JPL’s Asteroid Watch defines potentially hazardous asteroids as asteroids more than about 460 feet (140 meters) in size whose orbits bring them within 4.6 million miles (7.5 million kilometers) of Earth’s orbit around the Sun. This classification is not a statement that an object is on an impact trajectory. [c007]
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
