The Space Variable Objects Monitor (SVOM) is a small X-ray astronomy mission led by the Chinese National Space Administration (CNSA; China) and National Center for Space Studies (CNES; France). It is planned for a three year duration mission after its launch on June 22, 2024 from the Xichang launch facility in China aboard a Long March 2C rocket. It was placed into a 625 km altitude low earth orbit with a 30° inclination and a 96 minute orbital period.
Mission Characteristics
Lifetime
July 2024–(three year planned mission + 2 year extension)
Special Features
SVOM will have a number of astrophysics instruments working in concert with each other to localize and characterize gamma-ray bursts and their associated afterglows
Observations from space will be complemented by a number of ground segments including the Ground Based Wide Angle Camera (GWAC) and Ground Follow-up Telescopes (GFTs)
Lifetime
July 2024–(three year planned mission + 2 year extension)
Special Features
SVOM will have a number of astrophysics instruments working in concert with each other to localize and characterize gamma-ray bursts and their associated afterglows
Observations from space will be complemented by a number of ground segments including the Ground Based Wide Angle Camera (GWAC) and Ground Follow-up Telescopes (GFTs)
Payload
Instrument
Characteristic
Details
ECLAIRs telescope
Energy Range
4–250 keV
Field of View
89° × 89°
Angular Resolution
10′ (typical) 3′ for very bright GRBs
ECLAIRs is a coded mask wide Fields-of-View X-ray/gamma-ray instrument with 6400 CdTe detectors, cooled to -20°C. The detector is equipped with processing to trigger on unknown sources, such as gamma-ray bursts, rapidly slewing to bring the narrower-field MXT and VT instruments on source, as well as sending data and alert notices to the ground-based systems for co-observation.
Gamma Ray Burst Monitor (GRM)
Energy Range
15–5000 keV
Field of View
60° circular for each of three detectors
Angular Resolution
∼15°
GRM consists of three separate gamma-ray detectors inclined at 30° from the ECLAIRs pointing direction, giving them collectively a very similar field-of-view to ECLAIRs. Triangulation with the three detectors can narrow down gamma-ray burst location to a 15° × 15° area, sufficient for training other instruments on source. Each GRM will use a NaI crystal for detection with plastic scintillation across the detector front to distinguish gamma-rays from low energy electrons.
Microchannel X-ray Telescope (MXT)
Energy Range
0.2–10 keV
Focal Length
1.15 m
Field of View
1.1° × 1.1°
Angular Resolution
1′
Energy Resolution
∼75 eV at 1.5 keV
MXT is a soft X-ray telescope using micro-channel silicon pore focusing optics. The focal plane camera is an X-ray sensitive pnCCD array.
The Visible Telescope (VT)
Wavelength
450–650 nm (blue) 650–1000 nm (red/NIR)
Field of View
26′ × 26′
Angular Resolution
<1″
Sensitivity
V ≈22.5 (300 s exposure)
VT is a a Ritchey-Christian design telescope with a 40 cm primary mirror. The VT focal plane will be equipped with two 2048×2048 CCD cameras: one sensitive to blue, the other to red/near infrared: this is anticipated to be sensitive to objects of visual magnitude 22.5 with 300 seconds of observation: the VT thus should be able to see gamma-ray burst optical afterglow out to a redshift of 6.5, corresponding to 12 billion light years. VT is expected to about 60 gamma-ray burst sources a year.
ECLAIRs telescope
Energy Range
4–250 keV
Field of View
89° × 89°
Angular Resolution
10′ (typical) 3′ for very bright GRBs
ECLAIRs is a coded mask wide Fields-of-View X-ray/gamma-ray instrument with 6400 CdTe detectors, cooled to -20°C. The detector is equipped with processing to trigger on unknown sources, such as gamma-ray bursts, rapidly slewing to bring the narrower-field MXT and VT instruments on source, as well as sending data and alert notices to the ground-based systems for co-observation.
Gamma Ray Burst Monitor (GRM)
Energy Range
15–5000 keV
Field of View
60° circular for each of three detectors
Angular Resolution
∼15°
GRM consists of three separate gamma-ray detectors inclined at 30° from the ECLAIRs pointing direction, giving them collectively a very similar field-of-view to ECLAIRs. Triangulation with the three detectors can narrow down gamma-ray burst location to a 15° × 15° area, sufficient for training other instruments on source. Each GRM will use a NaI crystal for detection with plastic scintillation across the detector front to distinguish gamma-rays from low energy electrons.
Microchannel X-ray Telescope (MXT)
Energy Range
0.2–10 keV
Focal Length
1.15 m
Field of View
1.1° × 1.1°
Angular Resolution
1′
Energy Resolution
∼75 eV at 1.5 keV
MXT is a soft X-ray telescope using micro-channel silicon pore focusing optics. The focal plane camera is an X-ray sensitive pnCCD array.
The Visible Telescope (VT)
Wavelength
450–650 nm (blue) 650–1000 nm (red/NIR)
Field of View
26′ × 26′
Angular Resolution
<1″
Sensitivity
V ≈22.5 (300 s exposure)
VT is a a Ritchey-Christian design telescope with a 40 cm primary mirror. The VT focal plane will be equipped with two 2048×2048 CCD cameras: one sensitive to blue, the other to red/near infrared: this is anticipated to be sensitive to objects of visual magnitude 22.5 with 300 seconds of observation: the VT thus should be able to see gamma-ray burst optical afterglow out to a redshift of 6.5, corresponding to 12 billion light years. VT is expected to about 60 gamma-ray burst sources a year.
Science Goals
SVOM is primarily designed to detect and localize gamma-ray burst sources rapidly with high accuracy
